전체 코드 정리

.gitignore

@@ -120,6 +120,5 @@ $RECYCLE.BIN/
 *.lnk
 
 build/
-vendor/
 
 cpu_ctrl

Makefile

@@ -0,0 +1,68 @@
+PROJECT_NAME := cpu_ctrl
+PKG := "amuz.es/src/infra/$(PROJECT_NAME)"
+PKG_LIST := $(shell go list ${PKG}/... | grep -v /vendor/)
+GO_FILES := $(shell find . -name '*.go' | grep -v /vendor/ | grep -v _test.go)
+BUILD=`date +%FT%T%z`
+IS_DIRTY=$(shell sh -c '[[ `git diff --shortstat 2> /dev/null | tail -n1` != "" ]] && echo "-dirty"')
+VERSION?=$(shell git describe --exact-match 2> /dev/null || echo "`git symbolic-ref HEAD 2> /dev/null | cut -b 12-`-`git log --pretty=format:\"%h\" -1`")$(IS_DIRTY)
+DIST_NAME:= $(PROJECT_NAME).cpio.gz
+UTILS :=$(shell find cmd -type d -maxdepth 1 -mindepth 1|sed -e 's/cmd\///g')
+
+.PHONY: all vgo build
+
+all: build
+
+lint: ## Lint the files
+	@golint -set_exit_status ${PKG_LIST}
+
+test: ## Run unittests
+	@go test -short ${PKG_LIST}
+
+race: vgo ## Run data race detector
+	@go test -race -short ${PKG_LIST}
+
+msan: vgo ## Run memory sanitizer
+	@go test -msan -short ${PKG_LIST}
+
+vgo.lock: ## Get the dependencies
+	@echo -n ensure 'vgo' dependency resolver..
+	@go get -u golang.org/x/vgo
+	@echo done
+	@echo -n resolving dependencies..
+	@${GOPATH}/bin/vgo mod -fix -vendor -sync
+	@echo done
+	@touch vgo.lock
+
+vgo: vgo.lock
+
+build: vgo ## Build the binary file
+	@echo -n building..
+	@go build -ldflags "-w -s -X main.version=${VERSION} -X main.buildDate=${BUILD}" -o "${PROJECT_NAME}" .
+	@echo done
+
+build_util: vgo ## Build the binary file
+	@echo building..
+	@$(foreach UTIL,$(UTILS),printf "=> $(UTIL):" ;\
+	go build -ldflags "-w -s -X main.version=${VERSION} -X main.buildDate=${BUILD}"  -o "cmd/$(UTIL)/$(UTIL)" $(PKG)/cmd/$(UTIL) ;\
+	echo done ;)
+	@echo done
+
+clean: ## Remove previous build
+	@$(foreach UTIL,$(UTILS),rm -f "cmd/$(UTIL)/$(UTIL)";)
+	@rm -f "$(PROJECT_NAME)"
+	@rm -rf build
+
+version: ## Display version
+	@echo $(VERSION)
+
+help: ## Display this help screen
+	@grep -h -E '^[a-zA-Z_-]+:.*?## .*$$' $(MAKEFILE_LIST) | awk 'BEGIN {FS = ":.*?## "}; {printf "\033[36m%-30s\033[0m %s\n", $$1, $$2}'
+
+dist: build build_util
+	@rm -rf build
+	@mkdir -p build
+	@mv -f "$(PROJECT_NAME)" "build/$(PROJECT_NAME)"
+	@$(foreach UTIL,$(UTILS),mv -f "cmd/$(UTIL)/$(UTIL)" "build/$(UTIL)";)
+	@echo  -n archieving..
+	@pushd build 1> /dev/null 2>&1;find . -mindepth 1 ! -name $(DIST_NAME) | cpio --quiet -o |gzip > $(DIST_NAME) ;popd 1>/dev/null 2>&1
+	@echo " build/$(DIST_NAME)"

bootstrap.go

@@ -0,0 +1,168 @@
+package main // import "amuz.es/src/infra/cpu_ctrl"
+
+import (
+	"os"
+	"os/signal"
+	"syscall"
+	"fmt"
+	zlog "amuz.es/src/infra/goutils/logger/zap"
+	"go.uber.org/zap/zapcore"
+	"go.uber.org/multierr"
+	"amuz.es/src/infra/goutils/logger/rotater"
+	"amuz.es/src/infra/goutils/handler"
+	"amuz.es/src/infra/cpu_ctrl/daemon"
+	"amuz.es/src/infra/cpu_ctrl/producer"
+	"amuz.es/src/infra/cpu_ctrl/consumer"
+	"errors"
+	"go.uber.org/zap"
+)
+
+func finalCloser() {
+	if err := recover(); err != nil {
+		fmt.Fprintln(os.Stderr, err.(error).Error())
+		os.Exit(1)
+	}
+}
+
+// 로그 초기화
+func initLogger() func() {
+	// 로깅설정
+	formatter := zapcore.NewConsoleEncoder(zlog.LogCommonFormat)
+
+	// 전역 로거 초기화
+	var err error
+	logger, err = zlog.Init(
+		true,
+		formatter,
+		name,
+		"Stderr",
+		"",
+		nil,
+		zap.DebugLevel,
+	)
+
+	if err != nil {
+		panic(err)
+	}
+	// 로깅종료 및 exitcode 설정
+	return func() {}
+}
+
+// 애플리케이션이 종료를 위해 대기하는 부분
+func initContext(handler *handler.Handler) (func(), func()) {
+	exitSignal := make(chan os.Signal, 1)
+	// return waiter
+	return func() {
+		daemon.NotifyDaemon(daemon.DaemonStarted)
+		// 시그널 처리
+		signal.Notify(exitSignal, syscall.SIGINT, syscall.SIGTERM, syscall.SIGUSR1)
+		for {
+			select {
+			case <-handler.Done():
+				logger.Info("self destruct to close this application")
+				return
+			case initialErr := <-handler.Error():
+				// 복구불가능한 에러(들) 모아서 넘겨주는 부분
+				merged := initialErr
+				logger.Error("main: ", initialErr)
+				for {
+					select {
+					case anotherErr := <-handler.Error():
+						merged = multierr.Append(merged, anotherErr)
+						logger.Error("main: ", anotherErr)
+					default:
+						// panic을 발생시켜 컨텍스트를 에러를 전달한다.
+						panic(merged)
+					}
+				}
+			case sysSignal := <-exitSignal:
+				//handle signal
+				switch sysSignal {
+				case syscall.SIGUSR1:
+					rotater.Rotate()
+				default:
+					logger.Info(sysSignal.String(), " received")
+					return
+				}
+			}
+		}
+	}, // return closer
+		func() {
+			daemon.NotifyDaemon(daemon.DaemonStopping)
+			logger.Info("main: main context waiting..")
+			// http 서버 기다린다.
+			handler.GracefulWait()
+			close(exitSignal)
+		}
+}
+
+// 메인 웹서버 초기화
+func initProcessor(handler *handler.Handler) func() {
+
+	FanoutSpeed := func(sender <-chan producer.FanspeedInfo, receivers ...chan<- producer.FanspeedInfo) {
+		defer func() {
+			for _, receiver := range receivers {
+				close(receiver)
+			}
+			if err := recover(); err != nil {
+				handler.NotifyError(err.(error))
+			}
+		}()
+		for speed := range sender {
+			for _, receiver := range receivers {
+				select {
+				case receiver <- speed:
+				default:
+					logger.Warn("Some Fanspeed consumer blocked!")
+				}
+			}
+		}
+	}
+
+	FanoutTempeture := func(sender <-chan producer.TempetureInfo, receivers ...chan<- producer.TempetureInfo) {
+		defer func() {
+
+			for _, receiver := range receivers {
+				close(receiver)
+			}
+			if err := recover(); err != nil {
+				handler.NotifyError(err.(error))
+			}
+		}()
+		for tempeture := range sender {
+			for _, receiver := range receivers {
+				select {
+				case receiver <- tempeture:
+				default:
+					logger.Warn("Some Tempeture consumer blocked!")
+				}
+			}
+		}
+	}
+
+	processorCount := producer.GetProcessorCount()
+	if processorCount == 0 {
+		panic(errors.New("cpu not found!"))
+	}
+
+	tempetureInfoChan, fanspeedChan := producer.AggregateProcessorChannel(
+		handler,
+		*SampleInterval, processorCount,
+		*P, *I, *D,
+		*SetPoint,
+	)
+
+	fanController := consumer.NewFanControl(processorCount, *SampleInterval, handler)
+	metricLogger := consumer.NewInfluxMetric((*InfluxHost).String(), processorCount, handler)
+
+
+	handler.IncreaseWait()
+	go fanController.StartControl()
+	handler.IncreaseWait()
+	go metricLogger.StartLogging()
+
+	go FanoutTempeture(tempetureInfoChan, metricLogger.TempetureConsumer())
+	go FanoutSpeed(fanspeedChan, fanController.Consumer(), metricLogger.FanSpeedConsumer())
+
+	return func() {}
+}

consumer/influx_stat.go

@@ -1,16 +1,13 @@
 package consumer
 
 import (
-	"amuz.es/src/infra/cpu_ctrl/util"
-	"amuz.es/src/infra/cpu_ctrl/processor"
-	"amuz.es/src/infra/cpu_ctrl/logger"
-	"github.com/influxdata/influxdb/client/v2"
 	"time"
 	"strconv"
-)
-
-var (
-	influxLogger = logger.NewLogger("influx")
+	"amuz.es/src/infra/goutils/handler"
+	"amuz.es/src/infra/cpu_ctrl/producer"
+	"github.com/influxdata/influxdb/client/v2"
+	zlog "amuz.es/src/infra/goutils/logger/zap"
+	"go.uber.org/zap"
 )
 
 type data struct {
@@ -21,29 +18,31 @@ type data struct {
 type influxMetric struct {
 	host              string
 	processorCount    int
-	handler           util.Handler
-	fanSpeedConsumer  chan processor.FanspeedInfo
-	tempetureConsumer chan processor.TempetureInfo
+	handler           *handler.Handler
+	fanSpeedConsumer  chan producer.FanspeedInfo
+	tempetureConsumer chan producer.TempetureInfo
+	logger            *zap.SugaredLogger
 }
 
 type InfluxMetric interface {
-	FanSpeedConsumer() chan<- processor.FanspeedInfo
-	TempetureConsumer() chan<- processor.TempetureInfo
+	FanSpeedConsumer() chan<- producer.FanspeedInfo
+	TempetureConsumer() chan<- producer.TempetureInfo
 	StartLogging()
 }
 
-func NewInfluxMetric(host string, processorCount int, handler util.Handler) InfluxMetric {
+func NewInfluxMetric(host string, processorCount int, handler *handler.Handler) InfluxMetric {
 	return &influxMetric{
 		host:              host,
 		processorCount:    processorCount,
 		handler:           handler,
-		fanSpeedConsumer:  make(chan processor.FanspeedInfo, processorCount),
-		tempetureConsumer: make(chan processor.TempetureInfo, processorCount),
+		fanSpeedConsumer:  make(chan producer.FanspeedInfo, processorCount),
+		tempetureConsumer: make(chan producer.TempetureInfo, processorCount),
+		logger:            zlog.New(nil, "influx"),
 	}
 }
 
-func (m *influxMetric) FanSpeedConsumer() chan<- processor.FanspeedInfo   { return m.fanSpeedConsumer }
-func (m *influxMetric) TempetureConsumer() chan<- processor.TempetureInfo { return m.tempetureConsumer }
+func (m *influxMetric) FanSpeedConsumer() chan<- producer.FanspeedInfo   { return m.fanSpeedConsumer }
+func (m *influxMetric) TempetureConsumer() chan<- producer.TempetureInfo { return m.tempetureConsumer }
 
 func (m *influxMetric) StartLogging() {
 	defer m.handler.DecreaseWait()
@@ -53,17 +52,15 @@ func (m *influxMetric) StartLogging() {
 			m.handler.NotifyError(err.(error))
 		}
 	}()
-	defer close(m.fanSpeedConsumer)
-	defer close(m.tempetureConsumer)
 
-	defer influxLogger.Info("Metric logging stopped")
-	influxLogger.Info("Metric logging started")
+	defer m.logger.Info("Metric logging stopped")
+	m.logger.Info("Metric logging started")
 
 	var influxDbConn client.Client
 	for {
 		conn, err := client.NewUDPClient(client.UDPConfig{Addr: m.host,})
 		if err != nil {
-			influxLogger.Error(err)
+			m.logger.Error(err)
 		} else {
 			influxDbConn = conn
 			break
@@ -81,15 +78,23 @@ func (m *influxMetric) StartLogging() {
 	metricData := make([]data, m.processorCount)
 	sendData := make([]data, m.processorCount)
 
+	go func() {
+		for changedSpeed := range m.fanSpeedConsumer {
+			metricData[changedSpeed.Id].FanSpeed = changedSpeed.FanSpeed
+		}
+	}()
+
+	go func() {
+		for changedTempeture := range m.tempetureConsumer {
+			metricData[changedTempeture.Id].Tempeture = changedTempeture.Tempeture
+		}
+	}()
+
 	for {
 		select {
 		case <-ticker:
 			copy(sendData, metricData)
 			go m.sendPoint(influxDbConn, sendData)
-		case changedSpeed := <-m.fanSpeedConsumer:
-			metricData[changedSpeed.Id].FanSpeed = changedSpeed.FanSpeed
-		case changedTempeture := <-m.tempetureConsumer:
-			metricData[changedTempeture.Id].Tempeture = changedTempeture.Tempeture
 		case <-m.handler.Done():
 			return
 		}
@@ -104,7 +109,7 @@ func (m *influxMetric) sendPoint(
 		if point, err := m.getPoint(id, data, at); err == nil {
 			pointList = append(pointList, point)
 		} else {
-			influxLogger.Debugf("id %d err %s", id, err)
+			m.logger.Debugf("id %d err %s", id, err)
 		}
 	}
 
@@ -118,12 +123,12 @@ func (m *influxMetric) sendPoint(
 		Precision: "s",
 	})
 	if err != nil {
-		influxLogger.Warn(err)
+		m.logger.Warn(err)
 		return
 	}
 	batchPoint.AddPoints(pointList)
 	if err := influxDbConn.Write(batchPoint); err != nil {
-		influxLogger.Warn(err)
+		m.logger.Warn(err)
 	}
 
 }

consumer/speed_controller.go

@@ -3,39 +3,40 @@ package consumer
 import (
 	"fmt"
 	"os/exec"
-	"amuz.es/src/infra/cpu_ctrl/util"
 	"time"
-	"amuz.es/src/infra/cpu_ctrl/processor"
-	"amuz.es/src/infra/cpu_ctrl/logger"
+	zlog "amuz.es/src/infra/goutils/logger/zap"
 	"bytes"
+	"amuz.es/src/infra/goutils/handler"
+	"amuz.es/src/infra/cpu_ctrl/producer"
+	"go.uber.org/zap"
 )
 
-var (
-	fanspeedLogger = logger.NewLogger("fanspeed")
-)
+var ()
 
 type fanControl struct {
 	processorCount   int
-	handler          util.Handler
-	fanSpeedConsumer chan processor.FanspeedInfo
+	handler          *handler.Handler
+	fanSpeedConsumer chan producer.FanspeedInfo
 	sampleDuration   time.Duration
+	logger           *zap.SugaredLogger
 }
 
 type FanControl interface {
-	Consumer() chan<- processor.FanspeedInfo
+	Consumer() chan<- producer.FanspeedInfo
 	StartControl()
 }
 
-func NewFanControl(processorCount int, sampleDuration time.Duration, handler util.Handler) FanControl {
+func NewFanControl(processorCount int, sampleDuration time.Duration, handler *handler.Handler) FanControl {
 	return &fanControl{
 		processorCount:   processorCount,
 		handler:          handler,
-		fanSpeedConsumer: make(chan processor.FanspeedInfo, processorCount),
+		fanSpeedConsumer: make(chan producer.FanspeedInfo, processorCount),
 		sampleDuration:   sampleDuration,
+		logger:           zlog.New(nil, "fanspeed"),
 	}
 }
 
-func (c *fanControl) Consumer() chan<- processor.FanspeedInfo { return c.fanSpeedConsumer }
+func (c *fanControl) Consumer() chan<- producer.FanspeedInfo { return c.fanSpeedConsumer }
 
 func (c *fanControl) StartControl() {
 	defer c.handler.DecreaseWait()
@@ -45,8 +46,8 @@ func (c *fanControl) StartControl() {
 		}
 	}()
 	defer close(c.fanSpeedConsumer)
-	defer fanspeedLogger.Info("Fan control stopped")
-	fanspeedLogger.Info("Fan control started")
+	defer c.logger.Info("Fan control stopped")
+	c.logger.Info("Fan control started")
 
 	ticker := time.Tick(c.sampleDuration)
 	pastFanSpeedList, newFanSpeedList := make([]int, c.processorCount), make([]int, c.processorCount)
@@ -83,7 +84,7 @@ func (c *fanControl) applyFanspeed(newFanSpeedList []int) {
 		buf.WriteString(fmt.Sprintf("0x%x", item))
 		buf.WriteRune(' ')
 	}
-	fanspeedLogger.Infof("Commit fan speed with %s", buf.String())
+	c.logger.Infof("Commit fan speed with %s", buf.String())
 }
 
 func compareFanSpeed(old, new []int) bool {

go.mod

@@ -0,0 +1,28 @@
+module amuz.es/src/infra/cpu_ctrl
+
+require (
+	amuz.es/src/infra/goutils v0.1.0
+	github.com/StackExchange/wmi v0.0.0-20180412205111-cdffdb33acae
+	github.com/alecthomas/template v0.0.0-20160405071501-a0175ee3bccc
+	github.com/alecthomas/units v0.0.0-20151022065526-2efee857e7cf
+	github.com/coreos/go-systemd v0.0.0-20180525142239-a4887aeaa186
+	github.com/davecgh/go-spew v1.1.0
+	github.com/fastly/go-utils v0.0.0-20170926143046-88bf4bc30a29
+	github.com/go-ole/go-ole v1.2.1
+	github.com/influxdata/influxdb v1.5.4
+	github.com/jehiah/go-strftime v0.0.0-20171201141054-1d33003b3869
+	github.com/jonboulle/clockwork v0.1.0
+	github.com/lestrrat-go/envload v0.0.0-20180220234015-a3eb8ddeffcc
+	github.com/lestrrat-go/file-rotatelogs v0.0.0-20180607094457-00616292e771
+	github.com/lestrrat-go/strftime v0.0.0-20180414112801-59966ecb6d84
+	github.com/pkg/errors v0.8.0
+	github.com/pmezard/go-difflib v1.0.0
+	github.com/shirou/gopsutil v0.0.0-20180702150040-1c49dd8c6f1e
+	github.com/stretchr/testify v1.2.2
+	github.com/tebeka/strftime v0.0.0-20140926081919-3f9c7761e312
+	go.uber.org/atomic v1.3.2
+	go.uber.org/multierr v1.1.0
+	go.uber.org/zap v1.8.0
+	golang.org/x/sys v0.0.0-20180704094941-151529c776cd
+	gopkg.in/alecthomas/kingpin.v2 v2.2.6
+)

go.sum

@@ -0,0 +1,75 @@
+amuz.es/src/infra/goutils v0.1.0/go.mod h1:yMrniY0O2X+1YLkLJnw2rdPej+nu3rQpxFITU8h1iao=
+amuz.es/src/infra/goutils/handler v0.0.0-20180612161152-d9d96073e8bd/go.mod h1:G7mAYYxgmS0lVkHyy2hEOLQCFB0DlQFTMLWggykrydY=
+github.com/BurntSushi/toml v0.3.0 h1:e1/Ivsx3Z0FVTV0NSOv/aVgbUWyQuzj7DDnFblkRvsY=
+github.com/BurntSushi/toml v0.3.0/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03qcyfWMU=
+github.com/StackExchange/wmi v0.0.0-20180412205111-cdffdb33acae h1:Bqpru5NELaHtO/p7+TwRSKXWAMng4BCFBqVJ2eU8gpk=
+github.com/StackExchange/wmi v0.0.0-20180412205111-cdffdb33acae/go.mod h1:3eOhrUMpNV+6aFIbp5/iudMxNCF27Vw2OZgy4xEx0Fg=
+github.com/alecthomas/template v0.0.0-20160405071501-a0175ee3bccc/go.mod h1:LOuyumcjzFXgccqObfd/Ljyb9UuFJ6TxHnclSeseNhc=
+github.com/alecthomas/units v0.0.0-20151022065526-2efee857e7cf/go.mod h1:ybxpYRFXyAe+OPACYpWeL0wqObRcbAqCMya13uyzqw0=
+github.com/coreos/go-systemd v0.0.0-20180525142239-a4887aeaa186 h1:d3qD/+gm+uFN6SEjkWwnI0m55lJ1TKk1sqwKlmGvOxI=
+github.com/coreos/go-systemd v0.0.0-20180525142239-a4887aeaa186/go.mod h1:F5haX7vjVVG0kc13fIWeqUViNPyEJxv/OmvnBo0Yme4=
+github.com/coreos/go-systemd/daemon v0.0.0-20180525142239-a4887aeaa186/go.mod h1:G7mAYYxgmS0lVkHyy2hEOLQCFB0DlQFTMLWggykrydY=
+github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/davecgh/go-spew/spew v0.0.0-20180221232628-8991bc29aa16/go.mod h1:G7mAYYxgmS0lVkHyy2hEOLQCFB0DlQFTMLWggykrydY=
+github.com/fastly/go-utils v0.0.0-20170926143046-88bf4bc30a29/go.mod h1:Gdwt2ce0yfBxPvZrHkprdPPTTS3N5rwmLE8T22KBXlw=
+github.com/fastly/go-utils/strftime v0.0.0-20170926143046-88bf4bc30a29/go.mod h1:G7mAYYxgmS0lVkHyy2hEOLQCFB0DlQFTMLWggykrydY=
+github.com/go-ole/go-ole v1.2.1 h1:2lOsA72HgjxAuMlKpFiCbHTvu44PIVkZ5hqm3RSdI/E=
+github.com/go-ole/go-ole v1.2.1/go.mod h1:7FAglXiTm7HKlQRDeOQ6ZNUHidzCWXuZWq/1dTyBNF8=
+github.com/golang/protobuf v1.1.0/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
+github.com/golang/protobuf/proto v0.0.0-20180622174009-9eb2c01ac278/go.mod h1:G7mAYYxgmS0lVkHyy2hEOLQCFB0DlQFTMLWggykrydY=
+github.com/influxdata/influxdb v1.5.4 h1:Mk3papmtopxk9N397Y5ldgkf8RWxzNigCnTlfuljS7s=
+github.com/influxdata/influxdb v1.5.4/go.mod h1:qZna6X/4elxqT3yI9iZYdZrWWdeFOOprn86kgg4+IzY=
+github.com/influxdata/influxdb/client v0.0.0-20180704104005-ef4e525546f5/go.mod h1:G7mAYYxgmS0lVkHyy2hEOLQCFB0DlQFTMLWggykrydY=
+github.com/influxdata/influxdb/client/v2 v2.0.0-20180704104005-ef4e525546f5/go.mod h1:G7mAYYxgmS0lVkHyy2hEOLQCFB0DlQFTMLWggykrydY=
+github.com/jehiah/go-strftime v0.0.0-20171201141054-1d33003b3869/go.mod h1:cJ6Cj7dQo+O6GJNiMx+Pa94qKj+TG8ONdKHgMNIyyag=
+github.com/jonboulle/clockwork v0.1.0/go.mod h1:Ii8DK3G1RaLaWxj9trq07+26W01tbo22gdxWY5EU2bo=
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logger/logger.go

@@ -1,109 +0,0 @@
-package logger
-
-import (
-	"io"
-	"os"
-	"path"
-
-	"github.com/sirupsen/logrus"
-	"github.com/x-cray/logrus-prefixed-formatter"
-	"gopkg.in/natefinch/lumberjack.v2"
-)
-
-var (
-	logger    = logrus.StandardLogger()
-	rotaters  []*lumberjack.Logger
-	logDir    string
-	formatter = prefixed.TextFormatter{}
-)
-
-type Config struct {
-	FileName  string
-	MaxSizeMb int
-	MaxBackup int
-	MaxDay    int
-}
-
-type Logger interface {
-	Debugf(format string, args ...interface{})
-	Infof(format string, args ...interface{})
-	Printf(format string, args ...interface{})
-	Warnf(format string, args ...interface{})
-	Warningf(format string, args ...interface{})
-	Errorf(format string, args ...interface{})
-	Fatalf(format string, args ...interface{})
-	Panicf(format string, args ...interface{})
-	Debug(args ...interface{})
-	Info(args ...interface{})
-	Print(args ...interface{})
-	Warn(args ...interface{})
-	Warning(args ...interface{})
-	Error(args ...interface{})
-	Fatal(args ...interface{})
-	Panic(args ...interface{})
-	Debugln(args ...interface{})
-	Infoln(args ...interface{})
-	Println(args ...interface{})
-	Warnln(args ...interface{})
-	Warningln(args ...interface{})
-	Errorln(args ...interface{})
-	Fatalln(args ...interface{})
-	Panicln(args ...interface{})
-}
-
-func init() {
-	logger.Formatter = &formatter
-}
-func LoggerIsStd() bool {
-	return !formatter.DisableColors
-}
-func InitLogger(verbose bool, logDirArg string, config *Config) {
-	logDir = logDirArg
-	colorSupport, writer := NewLogWriter(config)
-	formatter.DisableColors = !colorSupport
-	logger.Out = writer
-	if verbose {
-		logger.Level = logrus.DebugLevel
-	} else {
-		logger.Level = logrus.InfoLevel
-	}
-}
-
-func NewLogger(prefix string) Logger {
-	return logrus.NewEntry(logger).WithField("prefix", prefix)
-}
-func NewLogWriter(config *Config) (bool, io.Writer) {
-	switch config.FileName {
-	case "Stdout":
-		return true, os.Stdout
-	case "Stderr":
-		return true, os.Stderr
-	default:
-		logpath := config.FileName
-		if logDir != "" {
-			logpath = path.Join(logDir, config.FileName)
-		}
-		logger.Info(" Attention!! log writes to ", config.FileName)
-		rotater := &lumberjack.Logger{
-			Filename:   logpath,
-			MaxSize:    config.MaxSizeMb, // megabytes
-			MaxBackups: config.MaxBackup,
-			MaxAge:     config.MaxDay, //days
-			LocalTime:  true,
-			Compress:   true,
-		}
-		rotaters = append(rotaters, rotater)
-		return false, rotater
-	}
-}
-
-func RotateLogger() {
-	if len(rotaters) == 0 {
-		return
-	}
-	logger.Info("rotating logger")
-	for _, rotater := range rotaters {
-		rotater.Rotate()
-	}
-	logger.Info("rotated")
-}

main.go

@@ -1,173 +1,84 @@
-package main
+package main // import "amuz.es/src/infra/cpu_ctrl"
 
 import (
-	"errors"
-	"os"
-	"os/signal"
-	"runtime"
-	"syscall"
 	"time"
-
-	"amuz.es/src/infra/cpu_ctrl/daemon"
-	"amuz.es/src/infra/cpu_ctrl/logger"
-	"amuz.es/src/infra/cpu_ctrl/processor"
-	"amuz.es/src/infra/cpu_ctrl/util"
-	"amuz.es/src/infra/cpu_ctrl/consumer"
-
+	"context"
+	"os"
+	"fmt"
+	"go.uber.org/zap"
 	"gopkg.in/alecthomas/kingpin.v2"
+	"runtime"
+	"amuz.es/src/infra/goutils/handler"
 )
 
+const (
+	name = "cpu_ctrl"
+)
+
+// command argument
 var (
-	app      = kingpin.New("cpu_ctrl", "Interactive CPU fan controller").Author("Sangbum Kim")
-	verbose  = app.Flag("verbose", "Enable verbose mode.").Short('v').Bool()
+	// 아래 부분은 컴파일시 하드코딩됨
+	buildDate, version string
+
+	app      = kingpin.New(name, fmt.Sprintf("%s -  metric collector", name)).Author("Amazing from here")
 	P        = app.Flag("proportional-gain", "Set proportional gain value.").Short('p').Default("1.0").Float64()
 	I        = app.Flag("integral-gain", "Set integral gain value.").Short('i').Default("0.4").Float64()
 	D        = app.Flag("derivative-gain", "Set derivative gain value.").Short('d').Default("2.0").Float64()
 	SetPoint = app.Flag("set-point", "Set pointe tempeture").Short('t').Default("40.0").Float64()
+	SampleInterval = app.Flag("interval", "Set sampling interval").Short('s').Default("1s").Duration()
+	InfluxHost = app.Flag("influx-host", "Set influx host").Short('h').Default("db:8089").TCP()
+	verbose  = app.Flag("verbose", "Enable verbose mode.").Short('v').Bool()
 
-	log = logger.NewLogger("cpu_ctrl")
+	// 아래 부분은 실행될때 평가됨
+	start = time.Now().Local()
+
+	logger = zap.L().Sugar()
 )
 
 func init() {
-	app.Version("0.3")
+	defer finalCloser()
+
+	runtime.GOMAXPROCS(runtime.NumCPU())
+
+	// command 설정 로드
+	app.Version(version)
 	if _, err := app.Parse(os.Args[1:]); err != nil {
-		panic(err)
-	}
-	logger.InitLogger(*verbose, "", &logger.Config{FileName: "Stderr"})
-
-	setMaxProcs()
-}
-
-func setMaxProcs() {
-	// TODO(vmarmol): Consider limiting if we have a CPU mask in effect.
-	// Allow as many threads as we have cores unless the user specified a value.
-	var numProcs int
-	// if *maxProcs < 1 {
-	numProcs = runtime.NumCPU()
-	// } else {
-	// numProcs = *maxProcs
-	// }
-	runtime.GOMAXPROCS(numProcs)
-
-	// Check if the setting was successful.
-	actualNumProcs := runtime.GOMAXPROCS(0)
-	if actualNumProcs != numProcs {
-		log.Printf("Specified max procs of %v but using %v\n", numProcs, actualNumProcs)
-	}
-}
-
-func FanoutSpeed(sender <-chan processor.FanspeedInfo, handler util.Handler, receivers ...chan<- processor.FanspeedInfo) {
-	defer handler.DecreaseWait()
-	defer func() {
-		if err := recover(); err != nil {
-			handler.NotifyError(err.(error))
-		}
-	}()
-	for {
-		select {
-		case tempeture := <-sender:
-			for _, receiver := range receivers {
-				select {
-				case receiver <- tempeture:
-				default:
-					log.Warn("Some Fanspeed consumer blocked!")
-				}
-			}
-			runtime.Gosched()
-
-		case <-handler.Done():
-			return
-		}
-	}
-}
-
-func FanoutTempeture(sender <-chan processor.TempetureInfo, handler util.Handler, receivers ...chan<- processor.TempetureInfo) {
-	defer handler.DecreaseWait()
-	defer func() {
-		if err := recover(); err != nil {
-			handler.NotifyError(err.(error))
-		}
-	}()
-	for {
-		select {
-		case tempeture := <-sender:
-			for _, receiver := range receivers {
-				select {
-				case receiver <- tempeture:
-				default:
-					log.Warn("Some Tempeture consumer blocked!")
-				}
-			}
-			runtime.Gosched()
-
-		case <-handler.Done():
-			return
-		}
+		fmt.Fprintln(os.Stderr, err.(error).Error())
+		os.Exit(1)
 	}
 }
 
+// 엔트리 포인트
 func main() {
+	defer finalCloser()
 
-	var (
-		processorCount = processor.GetProcessorCount()
-		processors     []processor.Processor
-		exitSignal     = make(chan os.Signal, 1)
-		handler        = util.NewHandler()
-		sampleDuration = time.Second
+	// 로그 초기화
+	loggerCleanup := initLogger()
+	defer loggerCleanup()
+
+	// 컨텍스트 생성
+	// handler내부에서도 로거를 이용하기 때문에 로깅부분 밑에 위치해야 된다.
+	mainHandler := handler.NewHandler(context.Background())
+
+	// hello ;-)
+	logger.Infof(
+		"%s(%s), built: %s",
+		name,
+		version,
+		buildDate,
 	)
-	log.Infof("Cpu fan controller")
 
-	if processorCount == 0 {
-		handler.NotifyError(errors.New("cpu not found!"))
-	}
-	var (
-		tempetureChannel = make(chan processor.TempetureInfo,1)
-		fanspeedChannel  = make(chan processor.FanspeedInfo,1)
-	)
-	processors = make([]processor.Processor, 0, processorCount)
-	for i := 0; i < processorCount; i++ {
-		if info, err := processor.NewProcessorInfo(handler, i, sampleDuration,
-			*P, *I, *D, *SetPoint, 0x64, 0x4,
-			tempetureChannel, fanspeedChannel,
-		);
-			err != nil {
-			handler.NotifyError(err)
-		} else {
-			processors = append(processors, info)
-			handler.IncreaseWait()
-			go info.StartMonitoring()
-		}
-	}
+	// 컨텍스트 띄우기
+	processorCleanup := initProcessor(mainHandler)
+	defer processorCleanup()
 
-	fanController := consumer.NewFanControl(processorCount, sampleDuration, handler)
-	metricLogger := consumer.NewInfluxMetric("db:8089", processorCount, handler)
+	// 뭔가 문제가 나거나 signal이 발생할 때 까지 애플리케이션이 종료로 빠지지 않게 잡아주는 부분
+	contextWatcher, contextCloser := initContext(mainHandler)
+	defer contextCloser()
 
-
-	handler.IncreaseWait()
-	go FanoutTempeture(tempetureChannel, handler, metricLogger.TempetureConsumer())
-	defer close(tempetureChannel)
-
-	handler.IncreaseWait()
-	go FanoutSpeed(fanspeedChannel, handler, fanController.Consumer(), metricLogger.FanSpeedConsumer())
-	defer close(fanspeedChannel)
-
-	handler.IncreaseWait()
-	go fanController.StartControl()
-	handler.IncreaseWait()
-	go metricLogger.StartLogging()
-
-	signal.Notify(exitSignal, syscall.SIGINT, syscall.SIGTERM, syscall.SIGHUP)
-	daemon.NotifyDaemon(daemon.DaemonStarted)
-	defer daemon.NotifyDaemon(daemon.DaemonStopping)
-	defer close(exitSignal)
-	defer handler.GracefullWait()
-
-	select {
-	case <-handler.Done():
-		log.Infoln("Service request to close this application")
-	case err := <-handler.Error():
-		log.Errorf("%s", err)
-	case sysSignal := <-exitSignal:
-		log.Warnf("SYSCALL! %s", sysSignal.String())
-	}
+	// ok
+	logger.Info("bootstrapped application ", time.Since(start), " ", time.Now())
+	contextWatcher()
+	logger.Info("served duration: ", time.Since(start))
 }
+

producer/cpu_temp_queue.go

@@ -0,0 +1,38 @@
+package producer
+
+
+
+import (
+	"container/list"
+)
+
+// 블럭되지 않는 큐체널
+func NewTempetureQueue() (chan<- TempetureInfo, <-chan TempetureInfo) {
+	send := make(chan TempetureInfo, 1)
+	receive := make(chan TempetureInfo, 1)
+	go manageTempetureQueue(send, receive)
+	return send, receive
+}
+
+func manageTempetureQueue(send <-chan TempetureInfo, receive chan<- TempetureInfo) {
+	queue := list.New()
+	defer close(receive)
+	for {
+		if front := queue.Front(); front == nil {
+			if value, ok := <-send; ok {
+				queue.PushBack(value)
+			} else {
+				break
+			}
+		} else {
+			select {
+			case receive <- front.Value.(TempetureInfo):
+				queue.Remove(front)
+			case value, ok := <-send:
+				if ok {
+					queue.PushBack(value)
+				}
+			}
+		}
+	}
+}

producer/fan_speed_queue.go

@@ -0,0 +1,36 @@
+package producer
+
+import (
+	"container/list"
+)
+
+// 블럭되지 않는 큐체널
+func NewFanspeedQueue() (chan<- FanspeedInfo, <-chan FanspeedInfo) {
+	send := make(chan FanspeedInfo, 1)
+	receive := make(chan FanspeedInfo, 1)
+	go manageFanspeedQueue(send, receive)
+	return send, receive
+}
+
+func manageFanspeedQueue(send <-chan FanspeedInfo, receive chan<- FanspeedInfo) {
+	queue := list.New()
+	defer close(receive)
+	for {
+		if front := queue.Front(); front == nil {
+			if value, ok := <-send; ok {
+				queue.PushBack(value)
+			} else {
+				break
+			}
+		} else {
+			select {
+			case receive <- front.Value.(FanspeedInfo):
+				queue.Remove(front)
+			case value, ok := <-send:
+				if ok {
+					queue.PushBack(value)
+				}
+			}
+		}
+	}
+}

producer/processor.go

@@ -1,4 +1,4 @@
-package processor
+package producer
 
 import (
 	"github.com/shirou/gopsutil/cpu"
@@ -9,16 +9,18 @@ import (
 	"time"
 	"sync"
 	"path"
-	"amuz.es/src/infra/cpu_ctrl/logger"
+	zlog "amuz.es/src/infra/goutils/logger/zap"
 	"io/ioutil"
 	"strings"
 	"amuz.es/src/infra/cpu_ctrl/pid"
-	"amuz.es/src/infra/cpu_ctrl/util"
+	"amuz.es/src/infra/goutils/handler"
 	"runtime"
+	"context"
+	"go.uber.org/zap"
 )
 
 type processor struct {
-	handler          util.Handler
+	handler          *handler.Handler
 	id               int
 	tempeturePath    string
 	tempeture        float64
@@ -29,6 +31,7 @@ type processor struct {
 	fanMaxSpeed      int
 	fanMinSpeed      int
 	fanSpeedChanged  chan<- FanspeedInfo
+	logger           *zap.SugaredLogger
 }
 
 type TempetureInfo struct {
@@ -55,10 +58,6 @@ type Processor interface {
 	normalizeFanspeed(float64) (int)
 }
 
-var (
-	log = logger.NewLogger("processor")
-)
-
 func GetProcessorCount() (maxcpu int) {
 	stat, err := cpu.Info()
 	if err != nil {
@@ -77,7 +76,7 @@ func GetProcessorCount() (maxcpu int) {
 }
 
 func NewProcessorInfo(
-	handler util.Handler,
+	handler *handler.Handler,
 	processorId int,
 	sampleDuration time.Duration,
 	P, I, D,
@@ -109,6 +108,7 @@ func NewProcessorInfo(
 			fanSpeedChanged:  fanSpeedChanged,
 			fanMaxSpeed:      maxNoob,
 			fanMinSpeed:      minNoob,
+			logger:           zlog.New(nil, "processor"),
 		}, nil
 	}
 }
@@ -119,7 +119,6 @@ func (p *processor) FanMaxSpeed() int   { return p.fanMaxSpeed }
 func (p *processor) FanMinSpeed() int   { return p.fanMinSpeed }
 
 func (p *processor) StartMonitoring() {
-	defer p.handler.DecreaseWait()
 	defer func() {
 		if err := recover(); err != nil {
 			p.handler.NotifyError(err.(error))
@@ -128,8 +127,8 @@ func (p *processor) StartMonitoring() {
 
 	tempeturePathGlob := path.Join(p.tempeturePath, "temp?_input")
 	ticker := time.Tick(p.sampleDuration)
-	defer log.Infof("Processor %d monitor stopped", p.id)
-	log.Infof("Processor %d monitor started with %s", p.id, p.sampleDuration)
+	defer p.logger.Infof("Processor %d monitor stopped", p.id)
+	p.logger.Infof("Processor %d monitor started with %s", p.id, p.sampleDuration)
 
 	for {
 		select {
@@ -155,7 +154,7 @@ func (p *processor) StartMonitoring() {
 				}
 			}
 			p.tempeture = highestTemp
-			log.Debugf("processor %d : tempeture changed %f", p.id, highestTemp)
+			p.logger.Debugf("processor %d : tempeture changed %f", p.id, highestTemp)
 
 			/*
 			SELECT mean("noob") as noob FROM "processor_cooling_fanspeed" WHERE $timeFilter GROUP BY "processor", time(5s) fill(previous)			CREATE CONTINUOUS QUERY "processor_cooling_fanspeed_5s" ON "core" BEGIN SELECT max("noob") AS "mean_noob" INTO  "processor_cooling_fanspeed_5s" FROM "processor_cooling_fanspeed" GROUP BY "processor", time(5s) fill(previous) END
@@ -173,7 +172,7 @@ func (p *processor) StartMonitoring() {
 				}
 			}
 			p.fanSpeed = fanspeed
-			log.Debugf("processor %d : fan changed 0x%x", p.id, fanspeed)
+			p.logger.Debugf("processor %d : fan changed 0x%x", p.id, fanspeed)
 		case <-p.handler.Done():
 			return
 		}
@@ -224,3 +223,43 @@ func (p *processor) normalizeFanspeed(response float64) (adjusted int) {
 	}
 	return
 }
+
+func AggregateProcessorChannel(
+	mainHandler *handler.Handler,
+	sampleDuration time.Duration,
+	processorCount int,
+	P, I, D, SetPoint float64,
+) (<-chan TempetureInfo, <-chan FanspeedInfo) {
+	mainHandler.IncreaseWait()
+	aggHandler := handler.NewHandler(context.Background())
+
+	var (
+		fin, fout = NewFanspeedQueue()
+		tin, tout = NewTempetureQueue()
+	)
+
+	go func() {
+		<-aggHandler.Done()
+		aggHandler.GracefulWait()
+		close(tin)
+		close(fin)
+		mainHandler.DecreaseWait()
+	}()
+
+	processors := make([]Processor, 0, processorCount)
+	for i := 0; i < processorCount; i++ {
+		if info, err := NewProcessorInfo(aggHandler, i, sampleDuration,
+			P, I, D, SetPoint,
+			0x64, 0x4,
+			tin, fin,
+		);
+			err != nil {
+			aggHandler.NotifyError(err)
+		} else {
+			processors = append(processors, info)
+			aggHandler.IncreaseWait()
+			go info.StartMonitoring()
+		}
+	}
+	return tout, fout
+}

util/handler.go

@@ -1,54 +0,0 @@
-package util
-
-import (
-	"sync"
-	"context"
-	"amuz.es/src/infra/cpu_ctrl/logger"
-)
-
-var (
-	log = logger.NewLogger("util")
-)
-
-type handler struct {
-	errorChan chan error
-	ctx       context.Context
-	canceler  context.CancelFunc
-	waiter    *sync.WaitGroup
-}
-
-type Handler interface {
-	NotifyError(err error)
-	Error() <-chan error
-	Done() <-chan struct{}
-	GracefullWait()
-	IncreaseWait()
-	DecreaseWait()
-}
-
-func NewHandler() Handler {
-	ctx, canceler := context.WithCancel(context.Background())
-	return &handler{
-		ctx:       ctx,
-		canceler:  canceler,
-		waiter:    &sync.WaitGroup{},
-		errorChan: make(chan error,1),
-	}
-}
-
-func (h *handler) NotifyError(err error) { h.errorChan <- err }
-func (h *handler) Error() <-chan error   { return h.errorChan }
-func (h *handler) Done() <-chan struct{} { return h.ctx.Done() }
-func (h *handler) GracefullWait() {
-	if h.ctx.Err() == nil {
-		h.canceler()
-	}
-	h.waiter.Wait()
-	close(h.errorChan)
-
-	for remainError := range h.errorChan {
-		log.Errorf("%s", remainError)
-	}
-}
-func (h *handler) IncreaseWait() { h.waiter.Add(1) }
-func (h *handler) DecreaseWait() { h.waiter.Done() }

vendor/amuz.es/src/infra/goutils/handler/handler.go

@@ -0,0 +1,48 @@
+package handler
+
+import (
+	"sync"
+	"context"
+	"log"
+)
+
+// 자식들을 기다리는 context waiter
+type Handler struct {
+	errorChan chan error
+	ctx       context.Context
+	canceler  context.CancelFunc
+	waiter    *sync.WaitGroup
+}
+
+func NewHandler(ctx context.Context) *Handler {
+	ctx, canceler := context.WithCancel(ctx)
+	return &Handler{
+		ctx:       ctx,
+		canceler:  canceler,
+		waiter:    &sync.WaitGroup{},
+		errorChan: make(chan error, 5),
+	}
+}
+
+func (h *Handler) NotifyError(err error) { h.errorChan <- err }
+func (h *Handler) Error() <-chan error   { return h.errorChan }
+func (h *Handler) Done() <-chan struct{} { return h.ctx.Done() }
+func (h *Handler) GracefulWait() {
+	if h.ctx.Err() == nil {
+		h.canceler()
+	}
+
+	h.waiter.Wait()
+	close(h.errorChan)
+
+	for remainError := range h.errorChan {
+		log.Println("remain errors ", remainError)
+	}
+}
+
+func (h *Handler) IncreaseWait() {
+	h.waiter.Add(1)
+}
+func (h *Handler) DecreaseWait() {
+	h.waiter.Done()
+}

vendor/amuz.es/src/infra/goutils/logger/common.go

@@ -0,0 +1,14 @@
+package logger
+
+import "io"
+
+type WriteSyncer interface {
+	io.WriteCloser
+	Sync() error
+}
+
+type RotateSyncer interface {
+	WriteSyncer
+	SetOnClose(func())
+	Rotate() error
+}

vendor/amuz.es/src/infra/goutils/logger/rotater/global.go

@@ -0,0 +1,51 @@
+package rotater
+
+import (
+	"os"
+	"path/filepath"
+	"log"
+	"amuz.es/src/infra/goutils/logger"
+	"github.com/lestrrat-go/file-rotatelogs"
+)
+
+var loggers RotateSyncerSet
+
+func NewLogWriter(FileName string, logDir string, options ...Option) (logger.RotateSyncer, error) {
+	switch FileName {
+	case "Stdout":
+		return NewLocked(os.Stdout), nil
+	case "Stderr":
+		return NewLocked(os.Stderr), nil
+	default:
+		logpath := FileName
+		if logDir != "" {
+			logpath = filepath.Join(logDir, FileName)
+		}
+		logpath,_ = filepath.Abs(logpath)
+		log.Println(" Attention!! log writes to ", logpath)
+		options=append(options,rotatelogs.WithLinkName(logpath))
+		if logWriter, err := NewRotater(logpath+".%Y%m%d", options...); err != nil {
+			return nil, err
+		} else {
+			loggers.Store(logWriter)
+			logWriter.SetOnClose(func() { loggers.Delete(logWriter) })
+			return logWriter, nil
+		}
+	}
+}
+
+func Rotate() {
+	loggers.Range(func(rotater logger.RotateSyncer) {
+		rotater.Sync()
+		rotater.Rotate()
+	})
+	log.Println("rotated")
+}
+
+func Close() {
+	loggers.Range(func(rotater logger.RotateSyncer) {
+		rotater.Sync()
+		rotater.Close()
+	})
+	log.Println("end of log")
+}

vendor/amuz.es/src/infra/goutils/logger/rotater/set_logcore.go

@@ -0,0 +1,47 @@
+package rotater
+
+import (
+	"sync"
+	"sync/atomic"
+	"amuz.es/src/infra/goutils/logger"
+)
+
+/**
+logger set
+ */
+type RotateSyncerSet struct {
+	storage sync.Map
+}
+
+func (s *RotateSyncerSet) Delete(key logger.RotateSyncer) {
+	s.storage.Delete(key)
+}
+func (s *RotateSyncerSet) Exist(key logger.RotateSyncer) (ok bool) {
+	_, ok = s.storage.Load(key)
+	return
+}
+func (s *RotateSyncerSet) SetNx(key logger.RotateSyncer) (bool) {
+	_, exist := s.storage.LoadOrStore(key, 0)
+	return !exist
+}
+func (s *RotateSyncerSet) Range(f func(key logger.RotateSyncer)) {
+	s.storage.Range(s.rangeWrap(f))
+}
+func (s *RotateSyncerSet) Store(key logger.RotateSyncer) {
+	s.storage.Store(key, 0)
+}
+func (s *RotateSyncerSet) rangeWrap(f func(key logger.RotateSyncer)) func(key, value interface{}) bool {
+	ok := true
+	return func(key, value interface{}) bool {
+		f(key.(logger.RotateSyncer))
+		return ok
+	}
+}
+
+func (s *RotateSyncerSet) Len() int {
+	var count uint64
+	s.Range(func(conn logger.RotateSyncer) {
+		atomic.AddUint64(&count, 1)
+	})
+	return int(count)
+}

vendor/amuz.es/src/infra/goutils/logger/rotater/wrapped.go

@@ -0,0 +1,39 @@
+package rotater
+
+import (
+	"sync"
+	"amuz.es/src/infra/goutils/logger"
+)
+
+type LockedWriteSyncer struct {
+	sync.Mutex
+	ws logger.WriteSyncer
+}
+
+// Lock wraps a WriteSyncer in a mutex to make it safe for concurrent use. In
+// particular, *os.Files must be locked before use.
+func NewLocked(ws logger.WriteSyncer) logger.RotateSyncer {
+	if lws, ok := ws.(*LockedWriteSyncer); ok {
+		// no need to layer on another lock
+		return lws
+	}
+	return &LockedWriteSyncer{ws: ws}
+}
+
+func (s *LockedWriteSyncer) Write(bs []byte) (int, error) {
+	s.Lock()
+	n, err := s.ws.Write(bs)
+	s.Unlock()
+	return n, err
+}
+
+func (s *LockedWriteSyncer) Sync() error {
+	s.Lock()
+	err := s.ws.Sync()
+	s.Unlock()
+	return err
+}
+
+func (r *LockedWriteSyncer) SetOnClose(closeFunc func()) {}
+func (r *LockedWriteSyncer) Rotate() (err error)         { return }
+func (r *LockedWriteSyncer) Close() (err error)          { return }

vendor/amuz.es/src/infra/goutils/logger/rotater/writeRotater.go

@@ -0,0 +1,51 @@
+package rotater
+
+import (
+	"sync"
+	"amuz.es/src/infra/goutils/logger"
+	"github.com/lestrrat-go/file-rotatelogs"
+)
+
+type Option = rotatelogs.Option
+
+type rotateSyncer struct {
+	setOnceOnclose *sync.Once
+	onClose        func()
+	*rotatelogs.RotateLogs
+}
+
+func NewRotater(filename string, options ...Option) (logger.RotateSyncer, error) {
+	if rotateLogger, err := rotatelogs.New(filename, options...); err != nil {
+		return nil, err
+	} else {
+		return &rotateSyncer{
+			setOnceOnclose: &sync.Once{},
+			RotateLogs:     rotateLogger,
+		}, nil
+	}
+}
+func (r *rotateSyncer) SetOnClose(closeFunc func()) {
+	r.setOnceOnclose.Do(func() {
+		r.onClose = closeFunc
+	})
+}
+
+func (r *rotateSyncer) Rotate() error {
+	return r.RotateLogs.Rotate()
+}
+func (r *rotateSyncer) Close() error {
+	defer func() {
+		if r.onClose != nil {
+			r.onClose()
+		}
+	}()
+	return r.RotateLogs.Close()
+}
+
+func (r *rotateSyncer) Sync() error {
+	return nil
+}
+
+func (s *rotateSyncer) Write(bs []byte) (int, error) {
+	return s.RotateLogs.Write(bs)
+}

vendor/amuz.es/src/infra/goutils/logger/zap/log_format.go

@@ -0,0 +1,17 @@
+package zap
+
+import "go.uber.org/zap/zapcore"
+
+var LogCommonFormat = zapcore.EncoderConfig{
+	TimeKey:        "ts",
+	LevelKey:       "level",
+	NameKey:        "logger",
+	CallerKey:      "caller",
+	MessageKey:     "msg",
+	StacktraceKey:  "stacktrace",
+	LineEnding:     zapcore.DefaultLineEnding,
+	EncodeLevel:    zapcore.CapitalLevelEncoder,
+	EncodeTime:     zapcore.ISO8601TimeEncoder,
+	EncodeDuration: zapcore.StringDurationEncoder,
+	EncodeCaller:   zapcore.ShortCallerEncoder,
+}

vendor/amuz.es/src/infra/goutils/logger/zap/logger.go

@@ -0,0 +1,114 @@
+package zap
+
+import (
+	"go.uber.org/zap"
+
+	"go.uber.org/zap/zapcore"
+	"amuz.es/src/infra/goutils/logger"
+	"amuz.es/src/infra/goutils/logger/rotater"
+)
+
+var (
+	defaultWriter             logger.RotateSyncer
+	defaultErrorOutputOptions []zap.Option
+	nopCloser                 = func() (err error) { return }
+)
+
+func init() {
+	zap.RedirectStdLog(zap.L())
+}
+
+func replaceGlobalLogger(newOne *zap.Logger) {
+	zap.ReplaceGlobals(newOne)
+	zap.RedirectStdLog(newOne)
+}
+
+func Init(
+	verbose bool,
+	formatter zapcore.Encoder,
+	mainLogName, logFilename, logDir string,
+	rotateOption []rotater.Option,
+	logLevel zapcore.Level,
+	additionalOptions ...zap.Option,
+) (*zap.SugaredLogger, error) {
+	level := zap.NewAtomicLevelAt(logLevel)
+	if defaultWriter, err := rotater.NewLogWriter(logFilename, logDir, rotateOption...); err != nil {
+		return nil, err
+	} else {
+		defaultErrorOutputOptions = []zap.Option{zap.ErrorOutput(defaultWriter)}
+		options := defaultErrorOutputOptions
+		if verbose {
+			options = append(options, zap.AddStacktrace(zap.NewAtomicLevelAt(zap.PanicLevel)))
+		}
+		// reset log option slice
+		options = append(options, additionalOptions...)
+
+		log := initLogger(defaultWriter, mainLogName, formatter, level, options...)
+
+		replaceGlobalLogger(log)
+		return log.Sugar(), nil
+	}
+}
+
+func New(parent *zap.SugaredLogger, moduleName string, options ...zap.Option) *zap.SugaredLogger {
+	var subLogger *zap.Logger
+	if parent == nil {
+		subLogger = zap.L().Named(moduleName)
+	} else {
+		subLogger = parent.Desugar().Named(moduleName)
+	}
+
+	subLogger.WithOptions(options...)
+
+	return subLogger.Sugar()
+}
+
+func NewOtherLogger(
+	formatter zapcore.Encoder,
+	moduleName, logFilename, logDir string,
+	rotateOption []rotater.Option,
+	logLevel zapcore.Level,
+	fields ...zapcore.Field,
+) (logger *zap.SugaredLogger, closer func() error, err error) {
+	loglevel := zap.NewAtomicLevelAt(logLevel)
+	logWriter, err := rotater.NewLogWriter(logFilename, logDir, rotateOption...)
+	if err != nil {
+		return
+	}
+	core := zapcore.NewCore(formatter, logWriter, loglevel)
+	closer = logWriter.Close
+	logger = zap.New(core, defaultErrorOutputOptions...).
+		Named(moduleName).With(fields...).Sugar()
+	return
+}
+
+func NewOtherLoggerWithOption(
+	formatter zapcore.Encoder,
+	moduleName, logFilename, logDir string,
+	rotateOption []rotater.Option,
+	logLevel zapcore.Level,
+	options []zap.Option,
+	fields ...zapcore.Field,
+) (logger *zap.SugaredLogger, closer func() error, err error) {
+	loglevel := zap.NewAtomicLevelAt(logLevel)
+	logWriter, err := rotater.NewLogWriter(logFilename, logDir, rotateOption...)
+	if err != nil {
+		return
+	}
+	core := zapcore.NewCore(formatter, logWriter, loglevel)
+	closer = logWriter.Close
+	options = append(defaultErrorOutputOptions, options...)
+	logger = zap.New(core, options...).
+		Named(moduleName).With(fields...).Sugar()
+	return
+}
+func initLogger(
+	writer zapcore.WriteSyncer,
+	moduleName string,
+	formatter zapcore.Encoder,
+	level zap.AtomicLevel,
+	options ...zap.Option,
+) *zap.Logger {
+	core := zapcore.NewCore(formatter, writer, level)
+	return zap.New(core, options...).Named(moduleName)
+}

vendor/amuz.es/src/infra/goutils/logger/zap/wrapped.go

@@ -0,0 +1,14 @@
+package zap
+
+import (
+	"go.uber.org/zap/zapcore"
+)
+
+type zapWrappedSyncer struct {
+	zapcore.WriteSyncer
+}
+
+func (r *zapWrappedSyncer) SetOnClose(closeFunc func()) {}
+func (r *zapWrappedSyncer) Rotate() (err error)         { return }
+func (r *zapWrappedSyncer) Close() (err error)          { return }
+func (r *zapWrappedSyncer) Sync() error                 { return r.WriteSyncer.Sync() }

vendor/github.com/StackExchange/wmi/LICENSE

@@ -0,0 +1,20 @@
+The MIT License (MIT)
+
+Copyright (c) 2013 Stack Exchange
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of
+this software and associated documentation files (the "Software"), to deal in
+the Software without restriction, including without limitation the rights to
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+the Software, and to permit persons to whom the Software is furnished to do so,
+subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

vendor/github.com/StackExchange/wmi/README.md

@@ -0,0 +1,6 @@
+wmi
+===
+
+Package wmi provides a WQL interface to Windows WMI.
+
+Note: It interfaces with WMI on the local machine, therefore it only runs on Windows.

vendor/github.com/StackExchange/wmi/swbemservices.go

@@ -0,0 +1,260 @@
+// +build windows
+
+package wmi
+
+import (
+	"fmt"
+	"reflect"
+	"runtime"
+	"sync"
+
+	"github.com/go-ole/go-ole"
+	"github.com/go-ole/go-ole/oleutil"
+)
+
+// SWbemServices is used to access wmi. See https://msdn.microsoft.com/en-us/library/aa393719(v=vs.85).aspx
+type SWbemServices struct {
+	//TODO: track namespace. Not sure if we can re connect to a different namespace using the same instance
+	cWMIClient            *Client //This could also be an embedded struct, but then we would need to branch on Client vs SWbemServices in the Query method
+	sWbemLocatorIUnknown  *ole.IUnknown
+	sWbemLocatorIDispatch *ole.IDispatch
+	queries               chan *queryRequest
+	closeError            chan error
+	lQueryorClose         sync.Mutex
+}
+
+type queryRequest struct {
+	query    string
+	dst      interface{}
+	args     []interface{}
+	finished chan error
+}
+
+// InitializeSWbemServices will return a new SWbemServices object that can be used to query WMI
+func InitializeSWbemServices(c *Client, connectServerArgs ...interface{}) (*SWbemServices, error) {
+	//fmt.Println("InitializeSWbemServices: Starting")
+	//TODO: implement connectServerArgs as optional argument for init with connectServer call
+	s := new(SWbemServices)
+	s.cWMIClient = c
+	s.queries = make(chan *queryRequest)
+	initError := make(chan error)
+	go s.process(initError)
+
+	err, ok := <-initError
+	if ok {
+		return nil, err //Send error to caller
+	}
+	//fmt.Println("InitializeSWbemServices: Finished")
+	return s, nil
+}
+
+// Close will clear and release all of the SWbemServices resources
+func (s *SWbemServices) Close() error {
+	s.lQueryorClose.Lock()
+	if s == nil || s.sWbemLocatorIDispatch == nil {
+		s.lQueryorClose.Unlock()
+		return fmt.Errorf("SWbemServices is not Initialized")
+	}
+	if s.queries == nil {
+		s.lQueryorClose.Unlock()
+		return fmt.Errorf("SWbemServices has been closed")
+	}
+	//fmt.Println("Close: sending close request")
+	var result error
+	ce := make(chan error)
+	s.closeError = ce //Race condition if multiple callers to close. May need to lock here
+	close(s.queries)  //Tell background to shut things down
+	s.lQueryorClose.Unlock()
+	err, ok := <-ce
+	if ok {
+		result = err
+	}
+	//fmt.Println("Close: finished")
+	return result
+}
+
+func (s *SWbemServices) process(initError chan error) {
+	//fmt.Println("process: starting background thread initialization")
+	//All OLE/WMI calls must happen on the same initialized thead, so lock this goroutine
+	runtime.LockOSThread()
+	defer runtime.LockOSThread()
+
+	err := ole.CoInitializeEx(0, ole.COINIT_MULTITHREADED)
+	if err != nil {
+		oleCode := err.(*ole.OleError).Code()
+		if oleCode != ole.S_OK && oleCode != S_FALSE {
+			initError <- fmt.Errorf("ole.CoInitializeEx error: %v", err)
+			return
+		}
+	}
+	defer ole.CoUninitialize()
+
+	unknown, err := oleutil.CreateObject("WbemScripting.SWbemLocator")
+	if err != nil {
+		initError <- fmt.Errorf("CreateObject SWbemLocator error: %v", err)
+		return
+	} else if unknown == nil {
+		initError <- ErrNilCreateObject
+		return
+	}
+	defer unknown.Release()
+	s.sWbemLocatorIUnknown = unknown
+
+	dispatch, err := s.sWbemLocatorIUnknown.QueryInterface(ole.IID_IDispatch)
+	if err != nil {
+		initError <- fmt.Errorf("SWbemLocator QueryInterface error: %v", err)
+		return
+	}
+	defer dispatch.Release()
+	s.sWbemLocatorIDispatch = dispatch
+
+	// we can't do the ConnectServer call outside the loop unless we find a way to track and re-init the connectServerArgs
+	//fmt.Println("process: initialized. closing initError")
+	close(initError)
+	//fmt.Println("process: waiting for queries")
+	for q := range s.queries {
+		//fmt.Printf("process: new query: len(query)=%d\n", len(q.query))
+		errQuery := s.queryBackground(q)
+		//fmt.Println("process: s.queryBackground finished")
+		if errQuery != nil {
+			q.finished <- errQuery
+		}
+		close(q.finished)
+	}
+	//fmt.Println("process: queries channel closed")
+	s.queries = nil //set channel to nil so we know it is closed
+	//TODO: I think the Release/Clear calls can panic if things are in a bad state.
+	//TODO: May need to recover from panics and send error to method caller instead.
+	close(s.closeError)
+}
+
+// Query runs the WQL query using a SWbemServices instance and appends the values to dst.
+//
+// dst must have type *[]S or *[]*S, for some struct type S. Fields selected in
+// the query must have the same name in dst. Supported types are all signed and
+// unsigned integers, time.Time, string, bool, or a pointer to one of those.
+// Array types are not supported.
+//
+// By default, the local machine and default namespace are used. These can be
+// changed using connectServerArgs. See
+// http://msdn.microsoft.com/en-us/library/aa393720.aspx for details.
+func (s *SWbemServices) Query(query string, dst interface{}, connectServerArgs ...interface{}) error {
+	s.lQueryorClose.Lock()
+	if s == nil || s.sWbemLocatorIDispatch == nil {
+		s.lQueryorClose.Unlock()
+		return fmt.Errorf("SWbemServices is not Initialized")
+	}
+	if s.queries == nil {
+		s.lQueryorClose.Unlock()
+		return fmt.Errorf("SWbemServices has been closed")
+	}
+
+	//fmt.Println("Query: Sending query request")
+	qr := queryRequest{
+		query:    query,
+		dst:      dst,
+		args:     connectServerArgs,
+		finished: make(chan error),
+	}
+	s.queries <- &qr
+	s.lQueryorClose.Unlock()
+	err, ok := <-qr.finished
+	if ok {
+		//fmt.Println("Query: Finished with error")
+		return err //Send error to caller
+	}
+	//fmt.Println("Query: Finished")
+	return nil
+}
+
+func (s *SWbemServices) queryBackground(q *queryRequest) error {
+	if s == nil || s.sWbemLocatorIDispatch == nil {
+		return fmt.Errorf("SWbemServices is not Initialized")
+	}
+	wmi := s.sWbemLocatorIDispatch //Should just rename in the code, but this will help as we break things apart
+	//fmt.Println("queryBackground: Starting")
+
+	dv := reflect.ValueOf(q.dst)
+	if dv.Kind() != reflect.Ptr || dv.IsNil() {
+		return ErrInvalidEntityType
+	}
+	dv = dv.Elem()
+	mat, elemType := checkMultiArg(dv)
+	if mat == multiArgTypeInvalid {
+		return ErrInvalidEntityType
+	}
+
+	// service is a SWbemServices
+	serviceRaw, err := oleutil.CallMethod(wmi, "ConnectServer", q.args...)
+	if err != nil {
+		return err
+	}
+	service := serviceRaw.ToIDispatch()
+	defer serviceRaw.Clear()
+
+	// result is a SWBemObjectSet
+	resultRaw, err := oleutil.CallMethod(service, "ExecQuery", q.query)
+	if err != nil {
+		return err
+	}
+	result := resultRaw.ToIDispatch()
+	defer resultRaw.Clear()
+
+	count, err := oleInt64(result, "Count")
+	if err != nil {
+		return err
+	}
+
+	enumProperty, err := result.GetProperty("_NewEnum")
+	if err != nil {
+		return err
+	}
+	defer enumProperty.Clear()
+
+	enum, err := enumProperty.ToIUnknown().IEnumVARIANT(ole.IID_IEnumVariant)
+	if err != nil {
+		return err
+	}
+	if enum == nil {
+		return fmt.Errorf("can't get IEnumVARIANT, enum is nil")
+	}
+	defer enum.Release()
+
+	// Initialize a slice with Count capacity
+	dv.Set(reflect.MakeSlice(dv.Type(), 0, int(count)))
+
+	var errFieldMismatch error
+	for itemRaw, length, err := enum.Next(1); length > 0; itemRaw, length, err = enum.Next(1) {
+		if err != nil {
+			return err
+		}
+
+		err := func() error {
+			// item is a SWbemObject, but really a Win32_Process
+			item := itemRaw.ToIDispatch()
+			defer item.Release()
+
+			ev := reflect.New(elemType)
+			if err = s.cWMIClient.loadEntity(ev.Interface(), item); err != nil {
+				if _, ok := err.(*ErrFieldMismatch); ok {
+					// We continue loading entities even in the face of field mismatch errors.
+					// If we encounter any other error, that other error is returned. Otherwise,
+					// an ErrFieldMismatch is returned.
+					errFieldMismatch = err
+				} else {
+					return err
+				}
+			}
+			if mat != multiArgTypeStructPtr {
+				ev = ev.Elem()
+			}
+			dv.Set(reflect.Append(dv, ev))
+			return nil
+		}()
+		if err != nil {
+			return err
+		}
+	}
+	//fmt.Println("queryBackground: Finished")
+	return errFieldMismatch
+}

vendor/github.com/StackExchange/wmi/swbemservices_test.go

@@ -0,0 +1,151 @@
+// +build windows
+
+package wmi
+
+import (
+	"fmt"
+	"runtime"
+	"testing"
+	"time"
+)
+
+func TestWbemQuery(t *testing.T) {
+	s, err := InitializeSWbemServices(DefaultClient)
+	if err != nil {
+		t.Fatalf("InitializeSWbemServices: %s", err)
+	}
+
+	var dst []Win32_Process
+	q := CreateQuery(&dst, "WHERE name='lsass.exe'")
+	errQuery := s.Query(q, &dst)
+	if errQuery != nil {
+		t.Fatalf("Query1: %s", errQuery)
+	}
+	count := len(dst)
+	if count < 1 {
+		t.Fatal("Query1: no results found for lsass.exe")
+	}
+	//fmt.Printf("dst[0].ProcessID=%d\n", dst[0].ProcessId)
+
+	q2 := CreateQuery(&dst, "WHERE name='svchost.exe'")
+	errQuery = s.Query(q2, &dst)
+	if errQuery != nil {
+		t.Fatalf("Query2: %s", errQuery)
+	}
+	count = len(dst)
+	if count < 1 {
+		t.Fatal("Query2: no results found for svchost.exe")
+	}
+	//for index, item := range dst {
+	//	fmt.Printf("dst[%d].ProcessID=%d\n", index, item.ProcessId)
+	//}
+	errClose := s.Close()
+	if errClose != nil {
+		t.Fatalf("Close: %s", errClose)
+	}
+}
+
+func TestWbemQueryNamespace(t *testing.T) {
+	s, err := InitializeSWbemServices(DefaultClient)
+	if err != nil {
+		t.Fatalf("InitializeSWbemServices: %s", err)
+	}
+	var dst []MSFT_NetAdapter
+	q := CreateQuery(&dst, "")
+	errQuery := s.Query(q, &dst, nil, "root\\StandardCimv2")
+	if errQuery != nil {
+		t.Fatalf("Query: %s", errQuery)
+	}
+	count := len(dst)
+	if count < 1 {
+		t.Fatal("Query: no results found for MSFT_NetAdapter in root\\StandardCimv2")
+	}
+	errClose := s.Close()
+	if errClose != nil {
+		t.Fatalf("Close: %s", errClose)
+	}
+}
+
+// Run using: go test -run TestWbemMemory -timeout 60m
+func TestWbemMemory(t *testing.T) {
+	s, err := InitializeSWbemServices(DefaultClient)
+	if err != nil {
+		t.Fatalf("InitializeSWbemServices: %s", err)
+	}
+	start := time.Now()
+	limit := 500000
+	fmt.Printf("Benchmark Iterations: %d (Memory should stabilize around 7MB after ~3000)\n", limit)
+	var privateMB, allocMB, allocTotalMB float64
+	for i := 0; i < limit; i++ {
+		privateMB, allocMB, allocTotalMB = WbemGetMemoryUsageMB(s)
+		if i%100 == 0 {
+			privateMB, allocMB, allocTotalMB = WbemGetMemoryUsageMB(s)
+			fmt.Printf("Time: %4ds  Count: %5d  Private Memory: %5.1fMB  MemStats.Alloc: %4.1fMB  MemStats.TotalAlloc: %5.1fMB\n", time.Now().Sub(start)/time.Second, i, privateMB, allocMB, allocTotalMB)
+		}
+	}
+	errClose := s.Close()
+	if errClose != nil {
+		t.Fatalf("Close: %s", err)
+	}
+	fmt.Printf("Final Time: %4ds  Private Memory: %5.1fMB  MemStats.Alloc: %4.1fMB  MemStats.TotalAlloc: %5.1fMB\n", time.Now().Sub(start)/time.Second, privateMB, allocMB, allocTotalMB)
+}
+
+func WbemGetMemoryUsageMB(s *SWbemServices) (float64, float64, float64) {
+	runtime.ReadMemStats(&mMemoryUsageMB)
+	errGetMemoryUsageMB = s.Query(qGetMemoryUsageMB, &dstGetMemoryUsageMB)
+	if errGetMemoryUsageMB != nil {
+		fmt.Println("ERROR GetMemoryUsage", errGetMemoryUsageMB)
+		return 0, 0, 0
+	}
+	return float64(dstGetMemoryUsageMB[0].WorkingSetPrivate) / MB, float64(mMemoryUsageMB.Alloc) / MB, float64(mMemoryUsageMB.TotalAlloc) / MB
+}
+
+//Run all benchmarks (should run for at least 60s to get a stable number):
+//go test -run=NONE -bench=Version -benchtime=120s
+
+//Individual benchmarks:
+//go test -run=NONE -bench=NewVersion -benchtime=120s
+func BenchmarkNewVersion(b *testing.B) {
+	s, err := InitializeSWbemServices(DefaultClient)
+	if err != nil {
+		b.Fatalf("InitializeSWbemServices: %s", err)
+	}
+	var dst []Win32_OperatingSystem
+	q := CreateQuery(&dst, "")
+	for n := 0; n < b.N; n++ {
+		errQuery := s.Query(q, &dst)
+		if errQuery != nil {
+			b.Fatalf("Query%d: %s", n, errQuery)
+		}
+		count := len(dst)
+		if count < 1 {
+			b.Fatalf("Query%d: no results found for Win32_OperatingSystem", n)
+		}
+	}
+	errClose := s.Close()
+	if errClose != nil {
+		b.Fatalf("Close: %s", errClose)
+	}
+}
+
+//go test -run=NONE -bench=OldVersion -benchtime=120s
+func BenchmarkOldVersion(b *testing.B) {
+	var dst []Win32_OperatingSystem
+	q := CreateQuery(&dst, "")
+	for n := 0; n < b.N; n++ {
+		errQuery := Query(q, &dst)
+		if errQuery != nil {
+			b.Fatalf("Query%d: %s", n, errQuery)
+		}
+		count := len(dst)
+		if count < 1 {
+			b.Fatalf("Query%d: no results found for Win32_OperatingSystem", n)
+		}
+	}
+}
+
+type MSFT_NetAdapter struct {
+	Name              string
+	InterfaceIndex    int
+	DriverDescription string
+}

vendor/github.com/StackExchange/wmi/wmi.go

@@ -0,0 +1,490 @@
+// +build windows
+
+/*
+Package wmi provides a WQL interface for WMI on Windows.
+
+Example code to print names of running processes:
+
+	type Win32_Process struct {
+		Name string
+	}
+
+	func main() {
+		var dst []Win32_Process
+		q := wmi.CreateQuery(&dst, "")
+		err := wmi.Query(q, &dst)
+		if err != nil {
+			log.Fatal(err)
+		}
+		for i, v := range dst {
+			println(i, v.Name)
+		}
+	}
+
+*/
+package wmi
+
+import (
+	"bytes"
+	"errors"
+	"fmt"
+	"log"
+	"os"
+	"reflect"
+	"runtime"
+	"strconv"
+	"strings"
+	"sync"
+	"time"
+
+	"github.com/go-ole/go-ole"
+	"github.com/go-ole/go-ole/oleutil"
+)
+
+var l = log.New(os.Stdout, "", log.LstdFlags)
+
+var (
+	ErrInvalidEntityType = errors.New("wmi: invalid entity type")
+	// ErrNilCreateObject is the error returned if CreateObject returns nil even
+	// if the error was nil.
+	ErrNilCreateObject = errors.New("wmi: create object returned nil")
+	lock               sync.Mutex
+)
+
+// S_FALSE is returned by CoInitializeEx if it was already called on this thread.
+const S_FALSE = 0x00000001
+
+// QueryNamespace invokes Query with the given namespace on the local machine.
+func QueryNamespace(query string, dst interface{}, namespace string) error {
+	return Query(query, dst, nil, namespace)
+}
+
+// Query runs the WQL query and appends the values to dst.
+//
+// dst must have type *[]S or *[]*S, for some struct type S. Fields selected in
+// the query must have the same name in dst. Supported types are all signed and
+// unsigned integers, time.Time, string, bool, or a pointer to one of those.
+// Array types are not supported.
+//
+// By default, the local machine and default namespace are used. These can be
+// changed using connectServerArgs. See
+// http://msdn.microsoft.com/en-us/library/aa393720.aspx for details.
+//
+// Query is a wrapper around DefaultClient.Query.
+func Query(query string, dst interface{}, connectServerArgs ...interface{}) error {
+	if DefaultClient.SWbemServicesClient == nil {
+		return DefaultClient.Query(query, dst, connectServerArgs...)
+	}
+	return DefaultClient.SWbemServicesClient.Query(query, dst, connectServerArgs...)
+}
+
+// A Client is an WMI query client.
+//
+// Its zero value (DefaultClient) is a usable client.
+type Client struct {
+	// NonePtrZero specifies if nil values for fields which aren't pointers
+	// should be returned as the field types zero value.
+	//
+	// Setting this to true allows stucts without pointer fields to be used
+	// without the risk failure should a nil value returned from WMI.
+	NonePtrZero bool
+
+	// PtrNil specifies if nil values for pointer fields should be returned
+	// as nil.
+	//
+	// Setting this to true will set pointer fields to nil where WMI
+	// returned nil, otherwise the types zero value will be returned.
+	PtrNil bool
+
+	// AllowMissingFields specifies that struct fields not present in the
+	// query result should not result in an error.
+	//
+	// Setting this to true allows custom queries to be used with full
+	// struct definitions instead of having to define multiple structs.
+	AllowMissingFields bool
+
+	// SWbemServiceClient is an optional SWbemServices object that can be
+	// initialized and then reused across multiple queries. If it is null
+	// then the method will initialize a new temporary client each time.
+	SWbemServicesClient *SWbemServices
+}
+
+// DefaultClient is the default Client and is used by Query, QueryNamespace
+var DefaultClient = &Client{}
+
+// Query runs the WQL query and appends the values to dst.
+//
+// dst must have type *[]S or *[]*S, for some struct type S. Fields selected in
+// the query must have the same name in dst. Supported types are all signed and
+// unsigned integers, time.Time, string, bool, or a pointer to one of those.
+// Array types are not supported.
+//
+// By default, the local machine and default namespace are used. These can be
+// changed using connectServerArgs. See
+// http://msdn.microsoft.com/en-us/library/aa393720.aspx for details.
+func (c *Client) Query(query string, dst interface{}, connectServerArgs ...interface{}) error {
+	dv := reflect.ValueOf(dst)
+	if dv.Kind() != reflect.Ptr || dv.IsNil() {
+		return ErrInvalidEntityType
+	}
+	dv = dv.Elem()
+	mat, elemType := checkMultiArg(dv)
+	if mat == multiArgTypeInvalid {
+		return ErrInvalidEntityType
+	}
+
+	lock.Lock()
+	defer lock.Unlock()
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
+	err := ole.CoInitializeEx(0, ole.COINIT_MULTITHREADED)
+	if err != nil {
+		oleCode := err.(*ole.OleError).Code()
+		if oleCode != ole.S_OK && oleCode != S_FALSE {
+			return err
+		}
+	}
+	defer ole.CoUninitialize()
+
+	unknown, err := oleutil.CreateObject("WbemScripting.SWbemLocator")
+	if err != nil {
+		return err
+	} else if unknown == nil {
+		return ErrNilCreateObject
+	}
+	defer unknown.Release()
+
+	wmi, err := unknown.QueryInterface(ole.IID_IDispatch)
+	if err != nil {
+		return err
+	}
+	defer wmi.Release()
+
+	// service is a SWbemServices
+	serviceRaw, err := oleutil.CallMethod(wmi, "ConnectServer", connectServerArgs...)
+	if err != nil {
+		return err
+	}
+	service := serviceRaw.ToIDispatch()
+	defer serviceRaw.Clear()
+
+	// result is a SWBemObjectSet
+	resultRaw, err := oleutil.CallMethod(service, "ExecQuery", query)
+	if err != nil {
+		return err
+	}
+	result := resultRaw.ToIDispatch()
+	defer resultRaw.Clear()
+
+	count, err := oleInt64(result, "Count")
+	if err != nil {
+		return err
+	}
+
+	enumProperty, err := result.GetProperty("_NewEnum")
+	if err != nil {
+		return err
+	}
+	defer enumProperty.Clear()
+
+	enum, err := enumProperty.ToIUnknown().IEnumVARIANT(ole.IID_IEnumVariant)
+	if err != nil {
+		return err
+	}
+	if enum == nil {
+		return fmt.Errorf("can't get IEnumVARIANT, enum is nil")
+	}
+	defer enum.Release()
+
+	// Initialize a slice with Count capacity
+	dv.Set(reflect.MakeSlice(dv.Type(), 0, int(count)))
+
+	var errFieldMismatch error
+	for itemRaw, length, err := enum.Next(1); length > 0; itemRaw, length, err = enum.Next(1) {
+		if err != nil {
+			return err
+		}
+
+		err := func() error {
+			// item is a SWbemObject, but really a Win32_Process
+			item := itemRaw.ToIDispatch()
+			defer item.Release()
+
+			ev := reflect.New(elemType)
+			if err = c.loadEntity(ev.Interface(), item); err != nil {
+				if _, ok := err.(*ErrFieldMismatch); ok {
+					// We continue loading entities even in the face of field mismatch errors.
+					// If we encounter any other error, that other error is returned. Otherwise,
+					// an ErrFieldMismatch is returned.
+					errFieldMismatch = err
+				} else {
+					return err
+				}
+			}
+			if mat != multiArgTypeStructPtr {
+				ev = ev.Elem()
+			}
+			dv.Set(reflect.Append(dv, ev))
+			return nil
+		}()
+		if err != nil {
+			return err
+		}
+	}
+	return errFieldMismatch
+}
+
+// ErrFieldMismatch is returned when a field is to be loaded into a different
+// type than the one it was stored from, or when a field is missing or
+// unexported in the destination struct.
+// StructType is the type of the struct pointed to by the destination argument.
+type ErrFieldMismatch struct {
+	StructType reflect.Type
+	FieldName  string
+	Reason     string
+}
+
+func (e *ErrFieldMismatch) Error() string {
+	return fmt.Sprintf("wmi: cannot load field %q into a %q: %s",
+		e.FieldName, e.StructType, e.Reason)
+}
+
+var timeType = reflect.TypeOf(time.Time{})
+
+// loadEntity loads a SWbemObject into a struct pointer.
+func (c *Client) loadEntity(dst interface{}, src *ole.IDispatch) (errFieldMismatch error) {
+	v := reflect.ValueOf(dst).Elem()
+	for i := 0; i < v.NumField(); i++ {
+		f := v.Field(i)
+		of := f
+		isPtr := f.Kind() == reflect.Ptr
+		if isPtr {
+			ptr := reflect.New(f.Type().Elem())
+			f.Set(ptr)
+			f = f.Elem()
+		}
+		n := v.Type().Field(i).Name
+		if !f.CanSet() {
+			return &ErrFieldMismatch{
+				StructType: of.Type(),
+				FieldName:  n,
+				Reason:     "CanSet() is false",
+			}
+		}
+		prop, err := oleutil.GetProperty(src, n)
+		if err != nil {
+			if !c.AllowMissingFields {
+				errFieldMismatch = &ErrFieldMismatch{
+					StructType: of.Type(),
+					FieldName:  n,
+					Reason:     "no such struct field",
+				}
+			}
+			continue
+		}
+		defer prop.Clear()
+
+		if prop.Value() == nil {
+			continue
+		}
+
+		switch val := prop.Value().(type) {
+		case int8, int16, int32, int64, int:
+			v := reflect.ValueOf(val).Int()
+			switch f.Kind() {
+			case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+				f.SetInt(v)
+			case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
+				f.SetUint(uint64(v))
+			default:
+				return &ErrFieldMismatch{
+					StructType: of.Type(),
+					FieldName:  n,
+					Reason:     "not an integer class",
+				}
+			}
+		case uint8, uint16, uint32, uint64:
+			v := reflect.ValueOf(val).Uint()
+			switch f.Kind() {
+			case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+				f.SetInt(int64(v))
+			case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
+				f.SetUint(v)
+			default:
+				return &ErrFieldMismatch{
+					StructType: of.Type(),
+					FieldName:  n,
+					Reason:     "not an integer class",
+				}
+			}
+		case string:
+			switch f.Kind() {
+			case reflect.String:
+				f.SetString(val)
+			case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+				iv, err := strconv.ParseInt(val, 10, 64)
+				if err != nil {
+					return err
+				}
+				f.SetInt(iv)
+			case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
+				uv, err := strconv.ParseUint(val, 10, 64)
+				if err != nil {
+					return err
+				}
+				f.SetUint(uv)
+			case reflect.Struct:
+				switch f.Type() {
+				case timeType:
+					if len(val) == 25 {
+						mins, err := strconv.Atoi(val[22:])
+						if err != nil {
+							return err
+						}
+						val = val[:22] + fmt.Sprintf("%02d%02d", mins/60, mins%60)
+					}
+					t, err := time.Parse("20060102150405.000000-0700", val)
+					if err != nil {
+						return err
+					}
+					f.Set(reflect.ValueOf(t))
+				}
+			}
+		case bool:
+			switch f.Kind() {
+			case reflect.Bool:
+				f.SetBool(val)
+			default:
+				return &ErrFieldMismatch{
+					StructType: of.Type(),
+					FieldName:  n,
+					Reason:     "not a bool",
+				}
+			}
+		case float32:
+			switch f.Kind() {
+			case reflect.Float32:
+				f.SetFloat(float64(val))
+			default:
+				return &ErrFieldMismatch{
+					StructType: of.Type(),
+					FieldName:  n,
+					Reason:     "not a Float32",
+				}
+			}
+		default:
+			if f.Kind() == reflect.Slice {
+				switch f.Type().Elem().Kind() {
+				case reflect.String:
+					safeArray := prop.ToArray()
+					if safeArray != nil {
+						arr := safeArray.ToValueArray()
+						fArr := reflect.MakeSlice(f.Type(), len(arr), len(arr))
+						for i, v := range arr {
+							s := fArr.Index(i)
+							s.SetString(v.(string))
+						}
+						f.Set(fArr)
+					}
+				case reflect.Uint8:
+					safeArray := prop.ToArray()
+					if safeArray != nil {
+						arr := safeArray.ToValueArray()
+						fArr := reflect.MakeSlice(f.Type(), len(arr), len(arr))
+						for i, v := range arr {
+							s := fArr.Index(i)
+							s.SetUint(reflect.ValueOf(v).Uint())
+						}
+						f.Set(fArr)
+					}
+				default:
+					return &ErrFieldMismatch{
+						StructType: of.Type(),
+						FieldName:  n,
+						Reason:     fmt.Sprintf("unsupported slice type (%T)", val),
+					}
+				}
+			} else {
+				typeof := reflect.TypeOf(val)
+				if typeof == nil && (isPtr || c.NonePtrZero) {
+					if (isPtr && c.PtrNil) || (!isPtr && c.NonePtrZero) {
+						of.Set(reflect.Zero(of.Type()))
+					}
+					break
+				}
+				return &ErrFieldMismatch{
+					StructType: of.Type(),
+					FieldName:  n,
+					Reason:     fmt.Sprintf("unsupported type (%T)", val),
+				}
+			}
+		}
+	}
+	return errFieldMismatch
+}
+
+type multiArgType int
+
+const (
+	multiArgTypeInvalid multiArgType = iota
+	multiArgTypeStruct
+	multiArgTypeStructPtr
+)
+
+// checkMultiArg checks that v has type []S, []*S for some struct type S.
+//
+// It returns what category the slice's elements are, and the reflect.Type
+// that represents S.
+func checkMultiArg(v reflect.Value) (m multiArgType, elemType reflect.Type) {
+	if v.Kind() != reflect.Slice {
+		return multiArgTypeInvalid, nil
+	}
+	elemType = v.Type().Elem()
+	switch elemType.Kind() {
+	case reflect.Struct:
+		return multiArgTypeStruct, elemType
+	case reflect.Ptr:
+		elemType = elemType.Elem()
+		if elemType.Kind() == reflect.Struct {
+			return multiArgTypeStructPtr, elemType
+		}
+	}
+	return multiArgTypeInvalid, nil
+}
+
+func oleInt64(item *ole.IDispatch, prop string) (int64, error) {
+	v, err := oleutil.GetProperty(item, prop)
+	if err != nil {
+		return 0, err
+	}
+	defer v.Clear()
+
+	i := int64(v.Val)
+	return i, nil
+}
+
+// CreateQuery returns a WQL query string that queries all columns of src. where
+// is an optional string that is appended to the query, to be used with WHERE
+// clauses. In such a case, the "WHERE" string should appear at the beginning.
+func CreateQuery(src interface{}, where string) string {
+	var b bytes.Buffer
+	b.WriteString("SELECT ")
+	s := reflect.Indirect(reflect.ValueOf(src))
+	t := s.Type()
+	if s.Kind() == reflect.Slice {
+		t = t.Elem()
+	}
+	if t.Kind() != reflect.Struct {
+		return ""
+	}
+	var fields []string
+	for i := 0; i < t.NumField(); i++ {
+		fields = append(fields, t.Field(i).Name)
+	}
+	b.WriteString(strings.Join(fields, ", "))
+	b.WriteString(" FROM ")
+	b.WriteString(t.Name())
+	b.WriteString(" " + where)
+	return b.String()
+}

vendor/github.com/StackExchange/wmi/wmi_test.go

@@ -0,0 +1,544 @@
+// +build windows
+
+package wmi
+
+import (
+	"encoding/json"
+	"fmt"
+	"os"
+	"reflect"
+	"runtime"
+	"runtime/debug"
+	"sync"
+	"testing"
+	"time"
+
+	ole "github.com/go-ole/go-ole"
+	"github.com/go-ole/go-ole/oleutil"
+)
+
+func TestQuery(t *testing.T) {
+	var dst []Win32_Process
+	q := CreateQuery(&dst, "")
+	err := Query(q, &dst)
+	if err != nil {
+		t.Fatal(err)
+	}
+}
+
+func TestFieldMismatch(t *testing.T) {
+	type s struct {
+		Name        string
+		HandleCount uint32
+		Blah        uint32
+	}
+	var dst []s
+	err := Query("SELECT Name, HandleCount FROM Win32_Process", &dst)
+	if err == nil || err.Error() != `wmi: cannot load field "Blah" into a "uint32": no such struct field` {
+		t.Error("Expected err field mismatch")
+	}
+}
+
+func TestStrings(t *testing.T) {
+	printed := false
+	f := func() {
+		var dst []Win32_Process
+		zeros := 0
+		q := CreateQuery(&dst, "")
+		for i := 0; i < 5; i++ {
+			err := Query(q, &dst)
+			if err != nil {
+				t.Fatal(err, q)
+			}
+			for _, d := range dst {
+				v := reflect.ValueOf(d)
+				for j := 0; j < v.NumField(); j++ {
+					f := v.Field(j)
+					if f.Kind() != reflect.String {
+						continue
+					}
+					s := f.Interface().(string)
+					if len(s) > 0 && s[0] == '\u0000' {
+						zeros++
+						if !printed {
+							printed = true
+							j, _ := json.MarshalIndent(&d, "", "  ")
+							t.Log("Example with \\u0000:\n", string(j))
+						}
+					}
+				}
+			}
+			fmt.Println("iter", i, "zeros:", zeros)
+		}
+		if zeros > 0 {
+			t.Error("> 0 zeros")
+		}
+	}
+
+	fmt.Println("Disabling GC")
+	debug.SetGCPercent(-1)
+	f()
+	fmt.Println("Enabling GC")
+	debug.SetGCPercent(100)
+	f()
+}
+
+func TestNamespace(t *testing.T) {
+	var dst []Win32_Process
+	q := CreateQuery(&dst, "")
+	err := QueryNamespace(q, &dst, `root\CIMV2`)
+	if err != nil {
+		t.Fatal(err)
+	}
+	dst = nil
+	err = QueryNamespace(q, &dst, `broken\nothing`)
+	if err == nil {
+		t.Fatal("expected error")
+	}
+}
+
+func TestCreateQuery(t *testing.T) {
+	type TestStruct struct {
+		Name  string
+		Count int
+	}
+	var dst []TestStruct
+	output := "SELECT Name, Count FROM TestStruct WHERE Count > 2"
+	tests := []interface{}{
+		&dst,
+		dst,
+		TestStruct{},
+		&TestStruct{},
+	}
+	for i, test := range tests {
+		if o := CreateQuery(test, "WHERE Count > 2"); o != output {
+			t.Error("bad output on", i, o)
+		}
+	}
+	if CreateQuery(3, "") != "" {
+		t.Error("expected empty string")
+	}
+}
+
+// Run using: go test -run TestMemoryWMISimple -timeout 60m
+func _TestMemoryWMISimple(t *testing.T) {
+	start := time.Now()
+	limit := 500000
+	fmt.Printf("Benchmark Iterations: %d (Memory should stabilize around 7MB after ~3000)\n", limit)
+	var privateMB, allocMB, allocTotalMB float64
+	//var dst []Win32_PerfRawData_PerfDisk_LogicalDisk
+	//q := CreateQuery(&dst, "")
+	for i := 0; i < limit; i++ {
+		privateMB, allocMB, allocTotalMB = GetMemoryUsageMB()
+		if i%1000 == 0 {
+			//privateMB, allocMB, allocTotalMB = GetMemoryUsageMB()
+			fmt.Printf("Time: %4ds  Count: %5d  Private Memory: %5.1fMB  MemStats.Alloc: %4.1fMB  MemStats.TotalAlloc: %5.1fMB\n", time.Now().Sub(start)/time.Second, i, privateMB, allocMB, allocTotalMB)
+		}
+		//Query(q, &dst)
+	}
+	//privateMB, allocMB, allocTotalMB = GetMemoryUsageMB()
+	fmt.Printf("Final Time: %4ds  Private Memory: %5.1fMB  MemStats.Alloc: %4.1fMB  MemStats.TotalAlloc: %5.1fMB\n", time.Now().Sub(start)/time.Second, privateMB, allocMB, allocTotalMB)
+}
+
+func _TestMemoryWMIConcurrent(t *testing.T) {
+	if testing.Short() {
+		return
+	}
+	start := time.Now()
+	limit := 50000
+	fmt.Println("Total Iterations:", limit)
+	fmt.Println("No panics mean it succeeded. Other errors are OK. Memory should stabilize after ~1500 iterations.")
+	runtime.GOMAXPROCS(2)
+	wg := sync.WaitGroup{}
+	wg.Add(2)
+	go func() {
+		for i := 0; i < limit; i++ {
+			if i%500 == 0 {
+				privateMB, allocMB, allocTotalMB := GetMemoryUsageMB()
+				fmt.Printf("Time: %4ds  Count: %4d  Private Memory: %5.1fMB  MemStats.Alloc: %4.1fMB  MemStats.TotalAlloc: %5.1fMB\n", time.Now().Sub(start)/time.Second, i, privateMB, allocMB, allocTotalMB)
+			}
+			var dst []Win32_PerfRawData_PerfDisk_LogicalDisk
+			q := CreateQuery(&dst, "")
+			err := Query(q, &dst)
+			if err != nil {
+				fmt.Println("ERROR disk", err)
+			}
+		}
+		wg.Done()
+	}()
+	go func() {
+		for i := 0; i > -limit; i-- {
+			//if i%500 == 0 {
+			//	fmt.Println(i)
+			//}
+			var dst []Win32_OperatingSystem
+			q := CreateQuery(&dst, "")
+			err := Query(q, &dst)
+			if err != nil {
+				fmt.Println("ERROR OS", err)
+			}
+		}
+		wg.Done()
+	}()
+	wg.Wait()
+	//privateMB, allocMB, allocTotalMB := GetMemoryUsageMB()
+	//fmt.Printf("Final Private Memory: %5.1fMB  MemStats.Alloc: %4.1fMB  MemStats.TotalAlloc: %5.1fMB\n", privateMB, allocMB, allocTotalMB)
+}
+
+var lockthread sync.Mutex
+var refcount1 int32
+var refcount2 int32
+var refcount3 int32
+
+// Test function showing memory leak in unknown.QueryInterface call on Server2016/Windows10
+func getRSS(url string, xmlhttp *ole.IDispatch, MinimalTest bool) (int, error) {
+
+	// call using url,nil to see memory leak
+	if xmlhttp == nil {
+		//Initialize inside loop if not passed in from outer section
+		lockthread.Lock()
+		defer lockthread.Unlock()
+		runtime.LockOSThread()
+		defer runtime.UnlockOSThread()
+
+		err := ole.CoInitializeEx(0, ole.COINIT_MULTITHREADED)
+		if err != nil {
+			oleCode := err.(*ole.OleError).Code()
+			if oleCode != ole.S_OK && oleCode != S_FALSE {
+				return 0, err
+			}
+		}
+		defer ole.CoUninitialize()
+
+		//fmt.Println("CreateObject Microsoft.XMLHTTP")
+		unknown, err := oleutil.CreateObject("Microsoft.XMLHTTP")
+		if err != nil {
+			return 0, err
+		}
+		defer func() { refcount1 += xmlhttp.Release() }()
+
+		//Memory leak occurs here
+		xmlhttp, err = unknown.QueryInterface(ole.IID_IDispatch)
+		if err != nil {
+			return 0, err
+		}
+		defer func() { refcount2 += xmlhttp.Release() }()
+		//Nothing below this really matters. Can be removed if you want a tighter loop
+	}
+
+	//fmt.Printf("Download %s\n", url)
+	openRaw, err := oleutil.CallMethod(xmlhttp, "open", "GET", url, false)
+	if err != nil {
+		return 0, err
+	}
+	defer openRaw.Clear()
+
+	if MinimalTest {
+		return 1, nil
+	}
+
+	//Initiate http request
+	sendRaw, err := oleutil.CallMethod(xmlhttp, "send", nil)
+	if err != nil {
+		return 0, err
+	}
+	defer sendRaw.Clear()
+	state := -1 // https://developer.mozilla.org/en-US/docs/Web/API/XMLHttpRequest/readyState
+	for state != 4 {
+		time.Sleep(5 * time.Millisecond)
+		stateRaw := oleutil.MustGetProperty(xmlhttp, "readyState")
+		state = int(stateRaw.Val)
+		stateRaw.Clear()
+	}
+
+	responseXMLRaw := oleutil.MustGetProperty(xmlhttp, "responseXml")
+	responseXML := responseXMLRaw.ToIDispatch()
+	defer responseXMLRaw.Clear()
+	itemsRaw := oleutil.MustCallMethod(responseXML, "selectNodes", "/rdf:RDF/item")
+	items := itemsRaw.ToIDispatch()
+	defer itemsRaw.Clear()
+	lengthRaw := oleutil.MustGetProperty(items, "length")
+	defer lengthRaw.Clear()
+	length := int(lengthRaw.Val)
+
+	/* This just bloats the TotalAlloc and slows the test down. Doesn't effect Private Working Set
+	for n := 0; n < length; n++ {
+		itemRaw := oleutil.MustGetProperty(items, "item", n)
+		item := itemRaw.ToIDispatch()
+		title := oleutil.MustCallMethod(item, "selectSingleNode", "title").ToIDispatch()
+
+		//fmt.Println(oleutil.MustGetProperty(title, "text").ToString())
+		textRaw := oleutil.MustGetProperty(title, "text")
+		textRaw.ToString()
+
+		link := oleutil.MustCallMethod(item, "selectSingleNode", "link").ToIDispatch()
+		//fmt.Println("  " + oleutil.MustGetProperty(link, "text").ToString())
+		textRaw2 := oleutil.MustGetProperty(link, "text")
+		textRaw2.ToString()
+
+		textRaw2.Clear()
+		link.Release()
+		textRaw.Clear()
+		title.Release()
+		itemRaw.Clear()
+	}
+	*/
+	return length, nil
+}
+
+// Testing go-ole/oleutil
+// Run using: go test -run TestMemoryOLE -timeout 60m
+// Code from https://github.com/go-ole/go-ole/blob/master/example/msxml/rssreader.go
+func _TestMemoryOLE(t *testing.T) {
+	defer func() {
+		if r := recover(); r != nil {
+			t.Error(r)
+		}
+	}()
+
+	start := time.Now()
+	limit := 50000000
+	url := "http://localhost/slashdot.xml" //http://rss.slashdot.org/Slashdot/slashdot"
+	fmt.Printf("Benchmark Iterations: %d (Memory should stabilize around 8MB to 12MB after ~2k full or 250k minimal)\n", limit)
+
+	//On Server 2016 or Windows 10 changing leakMemory=true will cause it to leak ~1.5MB per 10000 calls to unknown.QueryInterface
+	leakMemory := true
+
+	////////////////////////////////////////
+	//Start outer section
+	var unknown *ole.IUnknown
+	var xmlhttp *ole.IDispatch
+	if !leakMemory {
+		runtime.LockOSThread()
+		defer runtime.UnlockOSThread()
+
+		err := ole.CoInitializeEx(0, ole.COINIT_MULTITHREADED)
+		if err != nil {
+			oleCode := err.(*ole.OleError).Code()
+			if oleCode != ole.S_OK && oleCode != S_FALSE {
+				t.Fatal(err)
+			}
+		}
+		defer ole.CoUninitialize()
+
+		//fmt.Println("CreateObject Microsoft.XMLHTTP")
+		unknown, err = oleutil.CreateObject("Microsoft.XMLHTTP")
+		if err != nil {
+			t.Fatal(err)
+		}
+		defer unknown.Release()
+
+		//Memory leak starts here
+		xmlhttp, err = unknown.QueryInterface(ole.IID_IDispatch)
+		if err != nil {
+			t.Fatal(err)
+		}
+		defer xmlhttp.Release()
+	}
+	//End outer section
+	////////////////////////////////////////
+
+	totalItems := uint64(0)
+	for i := 0; i < limit; i++ {
+		if i%2000 == 0 {
+			privateMB, allocMB, allocTotalMB := GetMemoryUsageMB()
+			fmt.Printf("Time: %4ds  Count: %7d  Private Memory: %5.1fMB  MemStats.Alloc: %4.1fMB  MemStats.TotalAlloc: %5.1fMB  %7d/%7d\n", time.Now().Sub(start)/time.Second, i, privateMB, allocMB, allocTotalMB, refcount1, refcount2)
+		}
+		//This should use less than 10MB for 1 million iterations if xmlhttp was initialized above
+		//On Server 2016 or Windows 10 changing leakMemory=true above will cause it to leak ~1.5MB per 10000 calls to unknown.QueryInterface
+		count, err := getRSS(url, xmlhttp, true) //last argument is for Minimal test. Doesn't effect leak just overall allocations/time
+		if err != nil {
+			t.Fatal(err)
+		}
+		totalItems += uint64(count)
+	}
+	privateMB, allocMB, allocTotalMB := GetMemoryUsageMB()
+	fmt.Printf("Final totalItems: %d  Private Memory: %5.1fMB  MemStats.Alloc: %4.1fMB  MemStats.TotalAlloc: %5.1fMB\n", totalItems, privateMB, allocMB, allocTotalMB)
+}
+
+const MB = 1024 * 1024
+
+var (
+	mMemoryUsageMB      runtime.MemStats
+	errGetMemoryUsageMB error
+	dstGetMemoryUsageMB []Win32_PerfRawData_PerfProc_Process
+	filterProcessID     = fmt.Sprintf("WHERE IDProcess = %d", os.Getpid())
+	qGetMemoryUsageMB   = CreateQuery(&dstGetMemoryUsageMB, filterProcessID)
+)
+
+func GetMemoryUsageMB() (float64, float64, float64) {
+	runtime.ReadMemStats(&mMemoryUsageMB)
+	//errGetMemoryUsageMB = nil //Query(qGetMemoryUsageMB, &dstGetMemoryUsageMB) float64(dstGetMemoryUsageMB[0].WorkingSetPrivate)
+	errGetMemoryUsageMB = Query(qGetMemoryUsageMB, &dstGetMemoryUsageMB)
+	if errGetMemoryUsageMB != nil {
+		fmt.Println("ERROR GetMemoryUsage", errGetMemoryUsageMB)
+		return 0, 0, 0
+	}
+	return float64(dstGetMemoryUsageMB[0].WorkingSetPrivate) / MB, float64(mMemoryUsageMB.Alloc) / MB, float64(mMemoryUsageMB.TotalAlloc) / MB
+}
+
+type Win32_PerfRawData_PerfProc_Process struct {
+	IDProcess         uint32
+	WorkingSetPrivate uint64
+}
+
+type Win32_Process struct {
+	CSCreationClassName        string
+	CSName                     string
+	Caption                    *string
+	CommandLine                *string
+	CreationClassName          string
+	CreationDate               *time.Time
+	Description                *string
+	ExecutablePath             *string
+	ExecutionState             *uint16
+	Handle                     string
+	HandleCount                uint32
+	InstallDate                *time.Time
+	KernelModeTime             uint64
+	MaximumWorkingSetSize      *uint32
+	MinimumWorkingSetSize      *uint32
+	Name                       string
+	OSCreationClassName        string
+	OSName                     string
+	OtherOperationCount        uint64
+	OtherTransferCount         uint64
+	PageFaults                 uint32
+	PageFileUsage              uint32
+	ParentProcessId            uint32
+	PeakPageFileUsage          uint32
+	PeakVirtualSize            uint64
+	PeakWorkingSetSize         uint32
+	Priority                   uint32
+	PrivatePageCount           uint64
+	ProcessId                  uint32
+	QuotaNonPagedPoolUsage     uint32
+	QuotaPagedPoolUsage        uint32
+	QuotaPeakNonPagedPoolUsage uint32
+	QuotaPeakPagedPoolUsage    uint32
+	ReadOperationCount         uint64
+	ReadTransferCount          uint64
+	SessionId                  uint32
+	Status                     *string
+	TerminationDate            *time.Time
+	ThreadCount                uint32
+	UserModeTime               uint64
+	VirtualSize                uint64
+	WindowsVersion             string
+	WorkingSetSize             uint64
+	WriteOperationCount        uint64
+	WriteTransferCount         uint64
+}
+
+type Win32_PerfRawData_PerfDisk_LogicalDisk struct {
+	AvgDiskBytesPerRead          uint64
+	AvgDiskBytesPerRead_Base     uint32
+	AvgDiskBytesPerTransfer      uint64
+	AvgDiskBytesPerTransfer_Base uint32
+	AvgDiskBytesPerWrite         uint64
+	AvgDiskBytesPerWrite_Base    uint32
+	AvgDiskQueueLength           uint64
+	AvgDiskReadQueueLength       uint64
+	AvgDiskSecPerRead            uint32
+	AvgDiskSecPerRead_Base       uint32
+	AvgDiskSecPerTransfer        uint32
+	AvgDiskSecPerTransfer_Base   uint32
+	AvgDiskSecPerWrite           uint32
+	AvgDiskSecPerWrite_Base      uint32
+	AvgDiskWriteQueueLength      uint64
+	Caption                      *string
+	CurrentDiskQueueLength       uint32
+	Description                  *string
+	DiskBytesPerSec              uint64
+	DiskReadBytesPerSec          uint64
+	DiskReadsPerSec              uint32
+	DiskTransfersPerSec          uint32
+	DiskWriteBytesPerSec         uint64
+	DiskWritesPerSec             uint32
+	FreeMegabytes                uint32
+	Frequency_Object             uint64
+	Frequency_PerfTime           uint64
+	Frequency_Sys100NS           uint64
+	Name                         string
+	PercentDiskReadTime          uint64
+	PercentDiskReadTime_Base     uint64
+	PercentDiskTime              uint64
+	PercentDiskTime_Base         uint64
+	PercentDiskWriteTime         uint64
+	PercentDiskWriteTime_Base    uint64
+	PercentFreeSpace             uint32
+	PercentFreeSpace_Base        uint32
+	PercentIdleTime              uint64
+	PercentIdleTime_Base         uint64
+	SplitIOPerSec                uint32
+	Timestamp_Object             uint64
+	Timestamp_PerfTime           uint64
+	Timestamp_Sys100NS           uint64
+}
+
+type Win32_OperatingSystem struct {
+	BootDevice                                string
+	BuildNumber                               string
+	BuildType                                 string
+	Caption                                   *string
+	CodeSet                                   string
+	CountryCode                               string
+	CreationClassName                         string
+	CSCreationClassName                       string
+	CSDVersion                                *string
+	CSName                                    string
+	CurrentTimeZone                           int16
+	DataExecutionPrevention_Available         bool
+	DataExecutionPrevention_32BitApplications bool
+	DataExecutionPrevention_Drivers           bool
+	DataExecutionPrevention_SupportPolicy     *uint8
+	Debug                                     bool
+	Description                               *string
+	Distributed                               bool
+	EncryptionLevel                           uint32
+	ForegroundApplicationBoost                *uint8
+	FreePhysicalMemory                        uint64
+	FreeSpaceInPagingFiles                    uint64
+	FreeVirtualMemory                         uint64
+	InstallDate                               time.Time
+	LargeSystemCache                          *uint32
+	LastBootUpTime                            time.Time
+	LocalDateTime                             time.Time
+	Locale                                    string
+	Manufacturer                              string
+	MaxNumberOfProcesses                      uint32
+	MaxProcessMemorySize                      uint64
+	MUILanguages                              *[]string
+	Name                                      string
+	NumberOfLicensedUsers                     *uint32
+	NumberOfProcesses                         uint32
+	NumberOfUsers                             uint32
+	OperatingSystemSKU                        uint32
+	Organization                              string
+	OSArchitecture                            string
+	OSLanguage                                uint32
+	OSProductSuite                            uint32
+	OSType                                    uint16
+	OtherTypeDescription                      *string
+	PAEEnabled                                *bool
+	PlusProductID                             *string
+	PlusVersionNumber                         *string
+	PortableOperatingSystem                   bool
+	Primary                                   bool
+	ProductType                               uint32
+	RegisteredUser                            string
+	SerialNumber                              string
+	ServicePackMajorVersion                   uint16
+	ServicePackMinorVersion                   uint16
+	SizeStoredInPagingFiles                   uint64
+	Status                                    string
+	SuiteMask                                 uint32
+	SystemDevice                              string
+	SystemDirectory                           string
+	SystemDrive                               string
+	TotalSwapSpaceSize                        *uint64
+	TotalVirtualMemorySize                    uint64
+	TotalVisibleMemorySize                    uint64
+	Version                                   string
+	WindowsDirectory                          string
+}

vendor/github.com/alecthomas/template/LICENSE

@@ -0,0 +1,27 @@
+Copyright (c) 2012 The Go Authors. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+   * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+   * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+   * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

vendor/github.com/alecthomas/template/README.md

@@ -0,0 +1,25 @@
+# Go's `text/template` package with newline elision
+
+This is a fork of Go 1.4's [text/template](http://golang.org/pkg/text/template/) package with one addition: a backslash immediately after a closing delimiter will delete all subsequent newlines until a non-newline.
+
+eg.
+
+```
+{{if true}}\
+hello
+{{end}}\
+```
+
+Will result in:
+
+```
+hello\n
+```
+
+Rather than:
+
+```
+\n
+hello\n
+\n
+```

vendor/github.com/alecthomas/template/doc.go

@@ -0,0 +1,406 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+/*
+Package template implements data-driven templates for generating textual output.
+
+To generate HTML output, see package html/template, which has the same interface
+as this package but automatically secures HTML output against certain attacks.
+
+Templates are executed by applying them to a data structure. Annotations in the
+template refer to elements of the data structure (typically a field of a struct
+or a key in a map) to control execution and derive values to be displayed.
+Execution of the template walks the structure and sets the cursor, represented
+by a period '.' and called "dot", to the value at the current location in the
+structure as execution proceeds.
+
+The input text for a template is UTF-8-encoded text in any format.
+"Actions"--data evaluations or control structures--are delimited by
+"{{" and "}}"; all text outside actions is copied to the output unchanged.
+Actions may not span newlines, although comments can.
+
+Once parsed, a template may be executed safely in parallel.
+
+Here is a trivial example that prints "17 items are made of wool".
+
+	type Inventory struct {
+		Material string
+		Count    uint
+	}
+	sweaters := Inventory{"wool", 17}
+	tmpl, err := template.New("test").Parse("{{.Count}} items are made of {{.Material}}")
+	if err != nil { panic(err) }
+	err = tmpl.Execute(os.Stdout, sweaters)
+	if err != nil { panic(err) }
+
+More intricate examples appear below.
+
+Actions
+
+Here is the list of actions. "Arguments" and "pipelines" are evaluations of
+data, defined in detail below.
+
+*/
+//	{{/* a comment */}}
+//		A comment; discarded. May contain newlines.
+//		Comments do not nest and must start and end at the
+//		delimiters, as shown here.
+/*
+
+	{{pipeline}}
+		The default textual representation of the value of the pipeline
+		is copied to the output.
+
+	{{if pipeline}} T1 {{end}}
+		If the value of the pipeline is empty, no output is generated;
+		otherwise, T1 is executed.  The empty values are false, 0, any
+		nil pointer or interface value, and any array, slice, map, or
+		string of length zero.
+		Dot is unaffected.
+
+	{{if pipeline}} T1 {{else}} T0 {{end}}
+		If the value of the pipeline is empty, T0 is executed;
+		otherwise, T1 is executed.  Dot is unaffected.
+
+	{{if pipeline}} T1 {{else if pipeline}} T0 {{end}}
+		To simplify the appearance of if-else chains, the else action
+		of an if may include another if directly; the effect is exactly
+		the same as writing
+			{{if pipeline}} T1 {{else}}{{if pipeline}} T0 {{end}}{{end}}
+
+	{{range pipeline}} T1 {{end}}
+		The value of the pipeline must be an array, slice, map, or channel.
+		If the value of the pipeline has length zero, nothing is output;
+		otherwise, dot is set to the successive elements of the array,
+		slice, or map and T1 is executed. If the value is a map and the
+		keys are of basic type with a defined order ("comparable"), the
+		elements will be visited in sorted key order.
+
+	{{range pipeline}} T1 {{else}} T0 {{end}}
+		The value of the pipeline must be an array, slice, map, or channel.
+		If the value of the pipeline has length zero, dot is unaffected and
+		T0 is executed; otherwise, dot is set to the successive elements
+		of the array, slice, or map and T1 is executed.
+
+	{{template "name"}}
+		The template with the specified name is executed with nil data.
+
+	{{template "name" pipeline}}
+		The template with the specified name is executed with dot set
+		to the value of the pipeline.
+
+	{{with pipeline}} T1 {{end}}
+		If the value of the pipeline is empty, no output is generated;
+		otherwise, dot is set to the value of the pipeline and T1 is
+		executed.
+
+	{{with pipeline}} T1 {{else}} T0 {{end}}
+		If the value of the pipeline is empty, dot is unaffected and T0
+		is executed; otherwise, dot is set to the value of the pipeline
+		and T1 is executed.
+
+Arguments
+
+An argument is a simple value, denoted by one of the following.
+
+	- A boolean, string, character, integer, floating-point, imaginary
+	  or complex constant in Go syntax. These behave like Go's untyped
+	  constants, although raw strings may not span newlines.
+	- The keyword nil, representing an untyped Go nil.
+	- The character '.' (period):
+		.
+	  The result is the value of dot.
+	- A variable name, which is a (possibly empty) alphanumeric string
+	  preceded by a dollar sign, such as
+		$piOver2
+	  or
+		$
+	  The result is the value of the variable.
+	  Variables are described below.
+	- The name of a field of the data, which must be a struct, preceded
+	  by a period, such as
+		.Field
+	  The result is the value of the field. Field invocations may be
+	  chained:
+	    .Field1.Field2
+	  Fields can also be evaluated on variables, including chaining:
+	    $x.Field1.Field2
+	- The name of a key of the data, which must be a map, preceded
+	  by a period, such as
+		.Key
+	  The result is the map element value indexed by the key.
+	  Key invocations may be chained and combined with fields to any
+	  depth:
+	    .Field1.Key1.Field2.Key2
+	  Although the key must be an alphanumeric identifier, unlike with
+	  field names they do not need to start with an upper case letter.
+	  Keys can also be evaluated on variables, including chaining:
+	    $x.key1.key2
+	- The name of a niladic method of the data, preceded by a period,
+	  such as
+		.Method
+	  The result is the value of invoking the method with dot as the
+	  receiver, dot.Method(). Such a method must have one return value (of
+	  any type) or two return values, the second of which is an error.
+	  If it has two and the returned error is non-nil, execution terminates
+	  and an error is returned to the caller as the value of Execute.
+	  Method invocations may be chained and combined with fields and keys
+	  to any depth:
+	    .Field1.Key1.Method1.Field2.Key2.Method2
+	  Methods can also be evaluated on variables, including chaining:
+	    $x.Method1.Field
+	- The name of a niladic function, such as
+		fun
+	  The result is the value of invoking the function, fun(). The return
+	  types and values behave as in methods. Functions and function
+	  names are described below.
+	- A parenthesized instance of one the above, for grouping. The result
+	  may be accessed by a field or map key invocation.
+		print (.F1 arg1) (.F2 arg2)
+		(.StructValuedMethod "arg").Field
+
+Arguments may evaluate to any type; if they are pointers the implementation
+automatically indirects to the base type when required.
+If an evaluation yields a function value, such as a function-valued
+field of a struct, the function is not invoked automatically, but it
+can be used as a truth value for an if action and the like. To invoke
+it, use the call function, defined below.
+
+A pipeline is a possibly chained sequence of "commands". A command is a simple
+value (argument) or a function or method call, possibly with multiple arguments:
+
+	Argument
+		The result is the value of evaluating the argument.
+	.Method [Argument...]
+		The method can be alone or the last element of a chain but,
+		unlike methods in the middle of a chain, it can take arguments.
+		The result is the value of calling the method with the
+		arguments:
+			dot.Method(Argument1, etc.)
+	functionName [Argument...]
+		The result is the value of calling the function associated
+		with the name:
+			function(Argument1, etc.)
+		Functions and function names are described below.
+
+Pipelines
+
+A pipeline may be "chained" by separating a sequence of commands with pipeline
+characters '|'. In a chained pipeline, the result of the each command is
+passed as the last argument of the following command. The output of the final
+command in the pipeline is the value of the pipeline.
+
+The output of a command will be either one value or two values, the second of
+which has type error. If that second value is present and evaluates to
+non-nil, execution terminates and the error is returned to the caller of
+Execute.
+
+Variables
+
+A pipeline inside an action may initialize a variable to capture the result.
+The initialization has syntax
+
+	$variable := pipeline
+
+where $variable is the name of the variable. An action that declares a
+variable produces no output.
+
+If a "range" action initializes a variable, the variable is set to the
+successive elements of the iteration.  Also, a "range" may declare two
+variables, separated by a comma:
+
+	range $index, $element := pipeline
+
+in which case $index and $element are set to the successive values of the
+array/slice index or map key and element, respectively.  Note that if there is
+only one variable, it is assigned the element; this is opposite to the
+convention in Go range clauses.
+
+A variable's scope extends to the "end" action of the control structure ("if",
+"with", or "range") in which it is declared, or to the end of the template if
+there is no such control structure.  A template invocation does not inherit
+variables from the point of its invocation.
+
+When execution begins, $ is set to the data argument passed to Execute, that is,
+to the starting value of dot.
+
+Examples
+
+Here are some example one-line templates demonstrating pipelines and variables.
+All produce the quoted word "output":
+
+	{{"\"output\""}}
+		A string constant.
+	{{`"output"`}}
+		A raw string constant.
+	{{printf "%q" "output"}}
+		A function call.
+	{{"output" | printf "%q"}}
+		A function call whose final argument comes from the previous
+		command.
+	{{printf "%q" (print "out" "put")}}
+		A parenthesized argument.
+	{{"put" | printf "%s%s" "out" | printf "%q"}}
+		A more elaborate call.
+	{{"output" | printf "%s" | printf "%q"}}
+		A longer chain.
+	{{with "output"}}{{printf "%q" .}}{{end}}
+		A with action using dot.
+	{{with $x := "output" | printf "%q"}}{{$x}}{{end}}
+		A with action that creates and uses a variable.
+	{{with $x := "output"}}{{printf "%q" $x}}{{end}}
+		A with action that uses the variable in another action.
+	{{with $x := "output"}}{{$x | printf "%q"}}{{end}}
+		The same, but pipelined.
+
+Functions
+
+During execution functions are found in two function maps: first in the
+template, then in the global function map. By default, no functions are defined
+in the template but the Funcs method can be used to add them.
+
+Predefined global functions are named as follows.
+
+	and
+		Returns the boolean AND of its arguments by returning the
+		first empty argument or the last argument, that is,
+		"and x y" behaves as "if x then y else x". All the
+		arguments are evaluated.
+	call
+		Returns the result of calling the first argument, which
+		must be a function, with the remaining arguments as parameters.
+		Thus "call .X.Y 1 2" is, in Go notation, dot.X.Y(1, 2) where
+		Y is a func-valued field, map entry, or the like.
+		The first argument must be the result of an evaluation
+		that yields a value of function type (as distinct from
+		a predefined function such as print). The function must
+		return either one or two result values, the second of which
+		is of type error. If the arguments don't match the function
+		or the returned error value is non-nil, execution stops.
+	html
+		Returns the escaped HTML equivalent of the textual
+		representation of its arguments.
+	index
+		Returns the result of indexing its first argument by the
+		following arguments. Thus "index x 1 2 3" is, in Go syntax,
+		x[1][2][3]. Each indexed item must be a map, slice, or array.
+	js
+		Returns the escaped JavaScript equivalent of the textual
+		representation of its arguments.
+	len
+		Returns the integer length of its argument.
+	not
+		Returns the boolean negation of its single argument.
+	or
+		Returns the boolean OR of its arguments by returning the
+		first non-empty argument or the last argument, that is,
+		"or x y" behaves as "if x then x else y". All the
+		arguments are evaluated.
+	print
+		An alias for fmt.Sprint
+	printf
+		An alias for fmt.Sprintf
+	println
+		An alias for fmt.Sprintln
+	urlquery
+		Returns the escaped value of the textual representation of
+		its arguments in a form suitable for embedding in a URL query.
+
+The boolean functions take any zero value to be false and a non-zero
+value to be true.
+
+There is also a set of binary comparison operators defined as
+functions:
+
+	eq
+		Returns the boolean truth of arg1 == arg2
+	ne
+		Returns the boolean truth of arg1 != arg2
+	lt
+		Returns the boolean truth of arg1 < arg2
+	le
+		Returns the boolean truth of arg1 <= arg2
+	gt
+		Returns the boolean truth of arg1 > arg2
+	ge
+		Returns the boolean truth of arg1 >= arg2
+
+For simpler multi-way equality tests, eq (only) accepts two or more
+arguments and compares the second and subsequent to the first,
+returning in effect
+
+	arg1==arg2 || arg1==arg3 || arg1==arg4 ...
+
+(Unlike with || in Go, however, eq is a function call and all the
+arguments will be evaluated.)
+
+The comparison functions work on basic types only (or named basic
+types, such as "type Celsius float32"). They implement the Go rules
+for comparison of values, except that size and exact type are
+ignored, so any integer value, signed or unsigned, may be compared
+with any other integer value. (The arithmetic value is compared,
+not the bit pattern, so all negative integers are less than all
+unsigned integers.) However, as usual, one may not compare an int
+with a float32 and so on.
+
+Associated templates
+
+Each template is named by a string specified when it is created. Also, each
+template is associated with zero or more other templates that it may invoke by
+name; such associations are transitive and form a name space of templates.
+
+A template may use a template invocation to instantiate another associated
+template; see the explanation of the "template" action above. The name must be
+that of a template associated with the template that contains the invocation.
+
+Nested template definitions
+
+When parsing a template, another template may be defined and associated with the
+template being parsed. Template definitions must appear at the top level of the
+template, much like global variables in a Go program.
+
+The syntax of such definitions is to surround each template declaration with a
+"define" and "end" action.
+
+The define action names the template being created by providing a string
+constant. Here is a simple example:
+
+	`{{define "T1"}}ONE{{end}}
+	{{define "T2"}}TWO{{end}}
+	{{define "T3"}}{{template "T1"}} {{template "T2"}}{{end}}
+	{{template "T3"}}`
+
+This defines two templates, T1 and T2, and a third T3 that invokes the other two
+when it is executed. Finally it invokes T3. If executed this template will
+produce the text
+
+	ONE TWO
+
+By construction, a template may reside in only one association. If it's
+necessary to have a template addressable from multiple associations, the
+template definition must be parsed multiple times to create distinct *Template
+values, or must be copied with the Clone or AddParseTree method.
+
+Parse may be called multiple times to assemble the various associated templates;
+see the ParseFiles and ParseGlob functions and methods for simple ways to parse
+related templates stored in files.
+
+A template may be executed directly or through ExecuteTemplate, which executes
+an associated template identified by name. To invoke our example above, we
+might write,
+
+	err := tmpl.Execute(os.Stdout, "no data needed")
+	if err != nil {
+		log.Fatalf("execution failed: %s", err)
+	}
+
+or to invoke a particular template explicitly by name,
+
+	err := tmpl.ExecuteTemplate(os.Stdout, "T2", "no data needed")
+	if err != nil {
+		log.Fatalf("execution failed: %s", err)
+	}
+
+*/
+package template

vendor/github.com/alecthomas/template/example_test.go

@@ -0,0 +1,72 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package template_test
+
+import (
+	"log"
+	"os"
+
+	"github.com/alecthomas/template"
+)
+
+func ExampleTemplate() {
+	// Define a template.
+	const letter = `
+Dear {{.Name}},
+{{if .Attended}}
+It was a pleasure to see you at the wedding.{{else}}
+It is a shame you couldn't make it to the wedding.{{end}}
+{{with .Gift}}Thank you for the lovely {{.}}.
+{{end}}
+Best wishes,
+Josie
+`
+
+	// Prepare some data to insert into the template.
+	type Recipient struct {
+		Name, Gift string
+		Attended   bool
+	}
+	var recipients = []Recipient{
+		{"Aunt Mildred", "bone china tea set", true},
+		{"Uncle John", "moleskin pants", false},
+		{"Cousin Rodney", "", false},
+	}
+
+	// Create a new template and parse the letter into it.
+	t := template.Must(template.New("letter").Parse(letter))
+
+	// Execute the template for each recipient.
+	for _, r := range recipients {
+		err := t.Execute(os.Stdout, r)
+		if err != nil {
+			log.Println("executing template:", err)
+		}
+	}
+
+	// Output:
+	// Dear Aunt Mildred,
+	//
+	// It was a pleasure to see you at the wedding.
+	// Thank you for the lovely bone china tea set.
+	//
+	// Best wishes,
+	// Josie
+	//
+	// Dear Uncle John,
+	//
+	// It is a shame you couldn't make it to the wedding.
+	// Thank you for the lovely moleskin pants.
+	//
+	// Best wishes,
+	// Josie
+	//
+	// Dear Cousin Rodney,
+	//
+	// It is a shame you couldn't make it to the wedding.
+	//
+	// Best wishes,
+	// Josie
+}

vendor/github.com/alecthomas/template/examplefiles_test.go

@@ -0,0 +1,183 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package template_test
+
+import (
+	"io"
+	"io/ioutil"
+	"log"
+	"os"
+	"path/filepath"
+
+	"github.com/alecthomas/template"
+)
+
+// templateFile defines the contents of a template to be stored in a file, for testing.
+type templateFile struct {
+	name     string
+	contents string
+}
+
+func createTestDir(files []templateFile) string {
+	dir, err := ioutil.TempDir("", "template")
+	if err != nil {
+		log.Fatal(err)
+	}
+	for _, file := range files {
+		f, err := os.Create(filepath.Join(dir, file.name))
+		if err != nil {
+			log.Fatal(err)
+		}
+		defer f.Close()
+		_, err = io.WriteString(f, file.contents)
+		if err != nil {
+			log.Fatal(err)
+		}
+	}
+	return dir
+}
+
+// Here we demonstrate loading a set of templates from a directory.
+func ExampleTemplate_glob() {
+	// Here we create a temporary directory and populate it with our sample
+	// template definition files; usually the template files would already
+	// exist in some location known to the program.
+	dir := createTestDir([]templateFile{
+		// T0.tmpl is a plain template file that just invokes T1.
+		{"T0.tmpl", `T0 invokes T1: ({{template "T1"}})`},
+		// T1.tmpl defines a template, T1 that invokes T2.
+		{"T1.tmpl", `{{define "T1"}}T1 invokes T2: ({{template "T2"}}){{end}}`},
+		// T2.tmpl defines a template T2.
+		{"T2.tmpl", `{{define "T2"}}This is T2{{end}}`},
+	})
+	// Clean up after the test; another quirk of running as an example.
+	defer os.RemoveAll(dir)
+
+	// pattern is the glob pattern used to find all the template files.
+	pattern := filepath.Join(dir, "*.tmpl")
+
+	// Here starts the example proper.
+	// T0.tmpl is the first name matched, so it becomes the starting template,
+	// the value returned by ParseGlob.
+	tmpl := template.Must(template.ParseGlob(pattern))
+
+	err := tmpl.Execute(os.Stdout, nil)
+	if err != nil {
+		log.Fatalf("template execution: %s", err)
+	}
+	// Output:
+	// T0 invokes T1: (T1 invokes T2: (This is T2))
+}
+
+// This example demonstrates one way to share some templates
+// and use them in different contexts. In this variant we add multiple driver
+// templates by hand to an existing bundle of templates.
+func ExampleTemplate_helpers() {
+	// Here we create a temporary directory and populate it with our sample
+	// template definition files; usually the template files would already
+	// exist in some location known to the program.
+	dir := createTestDir([]templateFile{
+		// T1.tmpl defines a template, T1 that invokes T2.
+		{"T1.tmpl", `{{define "T1"}}T1 invokes T2: ({{template "T2"}}){{end}}`},
+		// T2.tmpl defines a template T2.
+		{"T2.tmpl", `{{define "T2"}}This is T2{{end}}`},
+	})
+	// Clean up after the test; another quirk of running as an example.
+	defer os.RemoveAll(dir)
+
+	// pattern is the glob pattern used to find all the template files.
+	pattern := filepath.Join(dir, "*.tmpl")
+
+	// Here starts the example proper.
+	// Load the helpers.
+	templates := template.Must(template.ParseGlob(pattern))
+	// Add one driver template to the bunch; we do this with an explicit template definition.
+	_, err := templates.Parse("{{define `driver1`}}Driver 1 calls T1: ({{template `T1`}})\n{{end}}")
+	if err != nil {
+		log.Fatal("parsing driver1: ", err)
+	}
+	// Add another driver template.
+	_, err = templates.Parse("{{define `driver2`}}Driver 2 calls T2: ({{template `T2`}})\n{{end}}")
+	if err != nil {
+		log.Fatal("parsing driver2: ", err)
+	}
+	// We load all the templates before execution. This package does not require
+	// that behavior but html/template's escaping does, so it's a good habit.
+	err = templates.ExecuteTemplate(os.Stdout, "driver1", nil)
+	if err != nil {
+		log.Fatalf("driver1 execution: %s", err)
+	}
+	err = templates.ExecuteTemplate(os.Stdout, "driver2", nil)
+	if err != nil {
+		log.Fatalf("driver2 execution: %s", err)
+	}
+	// Output:
+	// Driver 1 calls T1: (T1 invokes T2: (This is T2))
+	// Driver 2 calls T2: (This is T2)
+}
+
+// This example demonstrates how to use one group of driver
+// templates with distinct sets of helper templates.
+func ExampleTemplate_share() {
+	// Here we create a temporary directory and populate it with our sample
+	// template definition files; usually the template files would already
+	// exist in some location known to the program.
+	dir := createTestDir([]templateFile{
+		// T0.tmpl is a plain template file that just invokes T1.
+		{"T0.tmpl", "T0 ({{.}} version) invokes T1: ({{template `T1`}})\n"},
+		// T1.tmpl defines a template, T1 that invokes T2. Note T2 is not defined
+		{"T1.tmpl", `{{define "T1"}}T1 invokes T2: ({{template "T2"}}){{end}}`},
+	})
+	// Clean up after the test; another quirk of running as an example.
+	defer os.RemoveAll(dir)
+
+	// pattern is the glob pattern used to find all the template files.
+	pattern := filepath.Join(dir, "*.tmpl")
+
+	// Here starts the example proper.
+	// Load the drivers.
+	drivers := template.Must(template.ParseGlob(pattern))
+
+	// We must define an implementation of the T2 template. First we clone
+	// the drivers, then add a definition of T2 to the template name space.
+
+	// 1. Clone the helper set to create a new name space from which to run them.
+	first, err := drivers.Clone()
+	if err != nil {
+		log.Fatal("cloning helpers: ", err)
+	}
+	// 2. Define T2, version A, and parse it.
+	_, err = first.Parse("{{define `T2`}}T2, version A{{end}}")
+	if err != nil {
+		log.Fatal("parsing T2: ", err)
+	}
+
+	// Now repeat the whole thing, using a different version of T2.
+	// 1. Clone the drivers.
+	second, err := drivers.Clone()
+	if err != nil {
+		log.Fatal("cloning drivers: ", err)
+	}
+	// 2. Define T2, version B, and parse it.
+	_, err = second.Parse("{{define `T2`}}T2, version B{{end}}")
+	if err != nil {
+		log.Fatal("parsing T2: ", err)
+	}
+
+	// Execute the templates in the reverse order to verify the
+	// first is unaffected by the second.
+	err = second.ExecuteTemplate(os.Stdout, "T0.tmpl", "second")
+	if err != nil {
+		log.Fatalf("second execution: %s", err)
+	}
+	err = first.ExecuteTemplate(os.Stdout, "T0.tmpl", "first")
+	if err != nil {
+		log.Fatalf("first: execution: %s", err)
+	}
+
+	// Output:
+	// T0 (second version) invokes T1: (T1 invokes T2: (T2, version B))
+	// T0 (first version) invokes T1: (T1 invokes T2: (T2, version A))
+}

vendor/github.com/alecthomas/template/examplefunc_test.go

@@ -0,0 +1,55 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package template_test
+
+import (
+	"log"
+	"os"
+	"strings"
+
+	"github.com/alecthomas/template"
+)
+
+// This example demonstrates a custom function to process template text.
+// It installs the strings.Title function and uses it to
+// Make Title Text Look Good In Our Template's Output.
+func ExampleTemplate_func() {
+	// First we create a FuncMap with which to register the function.
+	funcMap := template.FuncMap{
+		// The name "title" is what the function will be called in the template text.
+		"title": strings.Title,
+	}
+
+	// A simple template definition to test our function.
+	// We print the input text several ways:
+	// - the original
+	// - title-cased
+	// - title-cased and then printed with %q
+	// - printed with %q and then title-cased.
+	const templateText = `
+Input: {{printf "%q" .}}
+Output 0: {{title .}}
+Output 1: {{title . | printf "%q"}}
+Output 2: {{printf "%q" . | title}}
+`
+
+	// Create a template, add the function map, and parse the text.
+	tmpl, err := template.New("titleTest").Funcs(funcMap).Parse(templateText)
+	if err != nil {
+		log.Fatalf("parsing: %s", err)
+	}
+
+	// Run the template to verify the output.
+	err = tmpl.Execute(os.Stdout, "the go programming language")
+	if err != nil {
+		log.Fatalf("execution: %s", err)
+	}
+
+	// Output:
+	// Input: "the go programming language"
+	// Output 0: The Go Programming Language
+	// Output 1: "The Go Programming Language"
+	// Output 2: "The Go Programming Language"
+}

vendor/github.com/alecthomas/template/exec.go

@@ -0,0 +1,845 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package template
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"reflect"
+	"runtime"
+	"sort"
+	"strings"
+
+	"github.com/alecthomas/template/parse"
+)
+
+// state represents the state of an execution. It's not part of the
+// template so that multiple executions of the same template
+// can execute in parallel.
+type state struct {
+	tmpl *Template
+	wr   io.Writer
+	node parse.Node // current node, for errors
+	vars []variable // push-down stack of variable values.
+}
+
+// variable holds the dynamic value of a variable such as $, $x etc.
+type variable struct {
+	name  string
+	value reflect.Value
+}
+
+// push pushes a new variable on the stack.
+func (s *state) push(name string, value reflect.Value) {
+	s.vars = append(s.vars, variable{name, value})
+}
+
+// mark returns the length of the variable stack.
+func (s *state) mark() int {
+	return len(s.vars)
+}
+
+// pop pops the variable stack up to the mark.
+func (s *state) pop(mark int) {
+	s.vars = s.vars[0:mark]
+}
+
+// setVar overwrites the top-nth variable on the stack. Used by range iterations.
+func (s *state) setVar(n int, value reflect.Value) {
+	s.vars[len(s.vars)-n].value = value
+}
+
+// varValue returns the value of the named variable.
+func (s *state) varValue(name string) reflect.Value {
+	for i := s.mark() - 1; i >= 0; i-- {
+		if s.vars[i].name == name {
+			return s.vars[i].value
+		}
+	}
+	s.errorf("undefined variable: %s", name)
+	return zero
+}
+
+var zero reflect.Value
+
+// at marks the state to be on node n, for error reporting.
+func (s *state) at(node parse.Node) {
+	s.node = node
+}
+
+// doublePercent returns the string with %'s replaced by %%, if necessary,
+// so it can be used safely inside a Printf format string.
+func doublePercent(str string) string {
+	if strings.Contains(str, "%") {
+		str = strings.Replace(str, "%", "%%", -1)
+	}
+	return str
+}
+
+// errorf formats the error and terminates processing.
+func (s *state) errorf(format string, args ...interface{}) {
+	name := doublePercent(s.tmpl.Name())
+	if s.node == nil {
+		format = fmt.Sprintf("template: %s: %s", name, format)
+	} else {
+		location, context := s.tmpl.ErrorContext(s.node)
+		format = fmt.Sprintf("template: %s: executing %q at <%s>: %s", location, name, doublePercent(context), format)
+	}
+	panic(fmt.Errorf(format, args...))
+}
+
+// errRecover is the handler that turns panics into returns from the top
+// level of Parse.
+func errRecover(errp *error) {
+	e := recover()
+	if e != nil {
+		switch err := e.(type) {
+		case runtime.Error:
+			panic(e)
+		case error:
+			*errp = err
+		default:
+			panic(e)
+		}
+	}
+}
+
+// ExecuteTemplate applies the template associated with t that has the given name
+// to the specified data object and writes the output to wr.
+// If an error occurs executing the template or writing its output,
+// execution stops, but partial results may already have been written to
+// the output writer.
+// A template may be executed safely in parallel.
+func (t *Template) ExecuteTemplate(wr io.Writer, name string, data interface{}) error {
+	tmpl := t.tmpl[name]
+	if tmpl == nil {
+		return fmt.Errorf("template: no template %q associated with template %q", name, t.name)
+	}
+	return tmpl.Execute(wr, data)
+}
+
+// Execute applies a parsed template to the specified data object,
+// and writes the output to wr.
+// If an error occurs executing the template or writing its output,
+// execution stops, but partial results may already have been written to
+// the output writer.
+// A template may be executed safely in parallel.
+func (t *Template) Execute(wr io.Writer, data interface{}) (err error) {
+	defer errRecover(&err)
+	value := reflect.ValueOf(data)
+	state := &state{
+		tmpl: t,
+		wr:   wr,
+		vars: []variable{{"$", value}},
+	}
+	t.init()
+	if t.Tree == nil || t.Root == nil {
+		var b bytes.Buffer
+		for name, tmpl := range t.tmpl {
+			if tmpl.Tree == nil || tmpl.Root == nil {
+				continue
+			}
+			if b.Len() > 0 {
+				b.WriteString(", ")
+			}
+			fmt.Fprintf(&b, "%q", name)
+		}
+		var s string
+		if b.Len() > 0 {
+			s = "; defined templates are: " + b.String()
+		}
+		state.errorf("%q is an incomplete or empty template%s", t.Name(), s)
+	}
+	state.walk(value, t.Root)
+	return
+}
+
+// Walk functions step through the major pieces of the template structure,
+// generating output as they go.
+func (s *state) walk(dot reflect.Value, node parse.Node) {
+	s.at(node)
+	switch node := node.(type) {
+	case *parse.ActionNode:
+		// Do not pop variables so they persist until next end.
+		// Also, if the action declares variables, don't print the result.
+		val := s.evalPipeline(dot, node.Pipe)
+		if len(node.Pipe.Decl) == 0 {
+			s.printValue(node, val)
+		}
+	case *parse.IfNode:
+		s.walkIfOrWith(parse.NodeIf, dot, node.Pipe, node.List, node.ElseList)
+	case *parse.ListNode:
+		for _, node := range node.Nodes {
+			s.walk(dot, node)
+		}
+	case *parse.RangeNode:
+		s.walkRange(dot, node)
+	case *parse.TemplateNode:
+		s.walkTemplate(dot, node)
+	case *parse.TextNode:
+		if _, err := s.wr.Write(node.Text); err != nil {
+			s.errorf("%s", err)
+		}
+	case *parse.WithNode:
+		s.walkIfOrWith(parse.NodeWith, dot, node.Pipe, node.List, node.ElseList)
+	default:
+		s.errorf("unknown node: %s", node)
+	}
+}
+
+// walkIfOrWith walks an 'if' or 'with' node. The two control structures
+// are identical in behavior except that 'with' sets dot.
+func (s *state) walkIfOrWith(typ parse.NodeType, dot reflect.Value, pipe *parse.PipeNode, list, elseList *parse.ListNode) {
+	defer s.pop(s.mark())
+	val := s.evalPipeline(dot, pipe)
+	truth, ok := isTrue(val)
+	if !ok {
+		s.errorf("if/with can't use %v", val)
+	}
+	if truth {
+		if typ == parse.NodeWith {
+			s.walk(val, list)
+		} else {
+			s.walk(dot, list)
+		}
+	} else if elseList != nil {
+		s.walk(dot, elseList)
+	}
+}
+
+// isTrue reports whether the value is 'true', in the sense of not the zero of its type,
+// and whether the value has a meaningful truth value.
+func isTrue(val reflect.Value) (truth, ok bool) {
+	if !val.IsValid() {
+		// Something like var x interface{}, never set. It's a form of nil.
+		return false, true
+	}
+	switch val.Kind() {
+	case reflect.Array, reflect.Map, reflect.Slice, reflect.String:
+		truth = val.Len() > 0
+	case reflect.Bool:
+		truth = val.Bool()
+	case reflect.Complex64, reflect.Complex128:
+		truth = val.Complex() != 0
+	case reflect.Chan, reflect.Func, reflect.Ptr, reflect.Interface:
+		truth = !val.IsNil()
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		truth = val.Int() != 0
+	case reflect.Float32, reflect.Float64:
+		truth = val.Float() != 0
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+		truth = val.Uint() != 0
+	case reflect.Struct:
+		truth = true // Struct values are always true.
+	default:
+		return
+	}
+	return truth, true
+}
+
+func (s *state) walkRange(dot reflect.Value, r *parse.RangeNode) {
+	s.at(r)
+	defer s.pop(s.mark())
+	val, _ := indirect(s.evalPipeline(dot, r.Pipe))
+	// mark top of stack before any variables in the body are pushed.
+	mark := s.mark()
+	oneIteration := func(index, elem reflect.Value) {
+		// Set top var (lexically the second if there are two) to the element.
+		if len(r.Pipe.Decl) > 0 {
+			s.setVar(1, elem)
+		}
+		// Set next var (lexically the first if there are two) to the index.
+		if len(r.Pipe.Decl) > 1 {
+			s.setVar(2, index)
+		}
+		s.walk(elem, r.List)
+		s.pop(mark)
+	}
+	switch val.Kind() {
+	case reflect.Array, reflect.Slice:
+		if val.Len() == 0 {
+			break
+		}
+		for i := 0; i < val.Len(); i++ {
+			oneIteration(reflect.ValueOf(i), val.Index(i))
+		}
+		return
+	case reflect.Map:
+		if val.Len() == 0 {
+			break
+		}
+		for _, key := range sortKeys(val.MapKeys()) {
+			oneIteration(key, val.MapIndex(key))
+		}
+		return
+	case reflect.Chan:
+		if val.IsNil() {
+			break
+		}
+		i := 0
+		for ; ; i++ {
+			elem, ok := val.Recv()
+			if !ok {
+				break
+			}
+			oneIteration(reflect.ValueOf(i), elem)
+		}
+		if i == 0 {
+			break
+		}
+		return
+	case reflect.Invalid:
+		break // An invalid value is likely a nil map, etc. and acts like an empty map.
+	default:
+		s.errorf("range can't iterate over %v", val)
+	}
+	if r.ElseList != nil {
+		s.walk(dot, r.ElseList)
+	}
+}
+
+func (s *state) walkTemplate(dot reflect.Value, t *parse.TemplateNode) {
+	s.at(t)
+	tmpl := s.tmpl.tmpl[t.Name]
+	if tmpl == nil {
+		s.errorf("template %q not defined", t.Name)
+	}
+	// Variables declared by the pipeline persist.
+	dot = s.evalPipeline(dot, t.Pipe)
+	newState := *s
+	newState.tmpl = tmpl
+	// No dynamic scoping: template invocations inherit no variables.
+	newState.vars = []variable{{"$", dot}}
+	newState.walk(dot, tmpl.Root)
+}
+
+// Eval functions evaluate pipelines, commands, and their elements and extract
+// values from the data structure by examining fields, calling methods, and so on.
+// The printing of those values happens only through walk functions.
+
+// evalPipeline returns the value acquired by evaluating a pipeline. If the
+// pipeline has a variable declaration, the variable will be pushed on the
+// stack. Callers should therefore pop the stack after they are finished
+// executing commands depending on the pipeline value.
+func (s *state) evalPipeline(dot reflect.Value, pipe *parse.PipeNode) (value reflect.Value) {
+	if pipe == nil {
+		return
+	}
+	s.at(pipe)
+	for _, cmd := range pipe.Cmds {
+		value = s.evalCommand(dot, cmd, value) // previous value is this one's final arg.
+		// If the object has type interface{}, dig down one level to the thing inside.
+		if value.Kind() == reflect.Interface && value.Type().NumMethod() == 0 {
+			value = reflect.ValueOf(value.Interface()) // lovely!
+		}
+	}
+	for _, variable := range pipe.Decl {
+		s.push(variable.Ident[0], value)
+	}
+	return value
+}
+
+func (s *state) notAFunction(args []parse.Node, final reflect.Value) {
+	if len(args) > 1 || final.IsValid() {
+		s.errorf("can't give argument to non-function %s", args[0])
+	}
+}
+
+func (s *state) evalCommand(dot reflect.Value, cmd *parse.CommandNode, final reflect.Value) reflect.Value {
+	firstWord := cmd.Args[0]
+	switch n := firstWord.(type) {
+	case *parse.FieldNode:
+		return s.evalFieldNode(dot, n, cmd.Args, final)
+	case *parse.ChainNode:
+		return s.evalChainNode(dot, n, cmd.Args, final)
+	case *parse.IdentifierNode:
+		// Must be a function.
+		return s.evalFunction(dot, n, cmd, cmd.Args, final)
+	case *parse.PipeNode:
+		// Parenthesized pipeline. The arguments are all inside the pipeline; final is ignored.
+		return s.evalPipeline(dot, n)
+	case *parse.VariableNode:
+		return s.evalVariableNode(dot, n, cmd.Args, final)
+	}
+	s.at(firstWord)
+	s.notAFunction(cmd.Args, final)
+	switch word := firstWord.(type) {
+	case *parse.BoolNode:
+		return reflect.ValueOf(word.True)
+	case *parse.DotNode:
+		return dot
+	case *parse.NilNode:
+		s.errorf("nil is not a command")
+	case *parse.NumberNode:
+		return s.idealConstant(word)
+	case *parse.StringNode:
+		return reflect.ValueOf(word.Text)
+	}
+	s.errorf("can't evaluate command %q", firstWord)
+	panic("not reached")
+}
+
+// idealConstant is called to return the value of a number in a context where
+// we don't know the type. In that case, the syntax of the number tells us
+// its type, and we use Go rules to resolve.  Note there is no such thing as
+// a uint ideal constant in this situation - the value must be of int type.
+func (s *state) idealConstant(constant *parse.NumberNode) reflect.Value {
+	// These are ideal constants but we don't know the type
+	// and we have no context.  (If it was a method argument,
+	// we'd know what we need.) The syntax guides us to some extent.
+	s.at(constant)
+	switch {
+	case constant.IsComplex:
+		return reflect.ValueOf(constant.Complex128) // incontrovertible.
+	case constant.IsFloat && !isHexConstant(constant.Text) && strings.IndexAny(constant.Text, ".eE") >= 0:
+		return reflect.ValueOf(constant.Float64)
+	case constant.IsInt:
+		n := int(constant.Int64)
+		if int64(n) != constant.Int64 {
+			s.errorf("%s overflows int", constant.Text)
+		}
+		return reflect.ValueOf(n)
+	case constant.IsUint:
+		s.errorf("%s overflows int", constant.Text)
+	}
+	return zero
+}
+
+func isHexConstant(s string) bool {
+	return len(s) > 2 && s[0] == '0' && (s[1] == 'x' || s[1] == 'X')
+}
+
+func (s *state) evalFieldNode(dot reflect.Value, field *parse.FieldNode, args []parse.Node, final reflect.Value) reflect.Value {
+	s.at(field)
+	return s.evalFieldChain(dot, dot, field, field.Ident, args, final)
+}
+
+func (s *state) evalChainNode(dot reflect.Value, chain *parse.ChainNode, args []parse.Node, final reflect.Value) reflect.Value {
+	s.at(chain)
+	// (pipe).Field1.Field2 has pipe as .Node, fields as .Field. Eval the pipeline, then the fields.
+	pipe := s.evalArg(dot, nil, chain.Node)
+	if len(chain.Field) == 0 {
+		s.errorf("internal error: no fields in evalChainNode")
+	}
+	return s.evalFieldChain(dot, pipe, chain, chain.Field, args, final)
+}
+
+func (s *state) evalVariableNode(dot reflect.Value, variable *parse.VariableNode, args []parse.Node, final reflect.Value) reflect.Value {
+	// $x.Field has $x as the first ident, Field as the second. Eval the var, then the fields.
+	s.at(variable)
+	value := s.varValue(variable.Ident[0])
+	if len(variable.Ident) == 1 {
+		s.notAFunction(args, final)
+		return value
+	}
+	return s.evalFieldChain(dot, value, variable, variable.Ident[1:], args, final)
+}
+
+// evalFieldChain evaluates .X.Y.Z possibly followed by arguments.
+// dot is the environment in which to evaluate arguments, while
+// receiver is the value being walked along the chain.
+func (s *state) evalFieldChain(dot, receiver reflect.Value, node parse.Node, ident []string, args []parse.Node, final reflect.Value) reflect.Value {
+	n := len(ident)
+	for i := 0; i < n-1; i++ {
+		receiver = s.evalField(dot, ident[i], node, nil, zero, receiver)
+	}
+	// Now if it's a method, it gets the arguments.
+	return s.evalField(dot, ident[n-1], node, args, final, receiver)
+}
+
+func (s *state) evalFunction(dot reflect.Value, node *parse.IdentifierNode, cmd parse.Node, args []parse.Node, final reflect.Value) reflect.Value {
+	s.at(node)
+	name := node.Ident
+	function, ok := findFunction(name, s.tmpl)
+	if !ok {
+		s.errorf("%q is not a defined function", name)
+	}
+	return s.evalCall(dot, function, cmd, name, args, final)
+}
+
+// evalField evaluates an expression like (.Field) or (.Field arg1 arg2).
+// The 'final' argument represents the return value from the preceding
+// value of the pipeline, if any.
+func (s *state) evalField(dot reflect.Value, fieldName string, node parse.Node, args []parse.Node, final, receiver reflect.Value) reflect.Value {
+	if !receiver.IsValid() {
+		return zero
+	}
+	typ := receiver.Type()
+	receiver, _ = indirect(receiver)
+	// Unless it's an interface, need to get to a value of type *T to guarantee
+	// we see all methods of T and *T.
+	ptr := receiver
+	if ptr.Kind() != reflect.Interface && ptr.CanAddr() {
+		ptr = ptr.Addr()
+	}
+	if method := ptr.MethodByName(fieldName); method.IsValid() {
+		return s.evalCall(dot, method, node, fieldName, args, final)
+	}
+	hasArgs := len(args) > 1 || final.IsValid()
+	// It's not a method; must be a field of a struct or an element of a map. The receiver must not be nil.
+	receiver, isNil := indirect(receiver)
+	if isNil {
+		s.errorf("nil pointer evaluating %s.%s", typ, fieldName)
+	}
+	switch receiver.Kind() {
+	case reflect.Struct:
+		tField, ok := receiver.Type().FieldByName(fieldName)
+		if ok {
+			field := receiver.FieldByIndex(tField.Index)
+			if tField.PkgPath != "" { // field is unexported
+				s.errorf("%s is an unexported field of struct type %s", fieldName, typ)
+			}
+			// If it's a function, we must call it.
+			if hasArgs {
+				s.errorf("%s has arguments but cannot be invoked as function", fieldName)
+			}
+			return field
+		}
+		s.errorf("%s is not a field of struct type %s", fieldName, typ)
+	case reflect.Map:
+		// If it's a map, attempt to use the field name as a key.
+		nameVal := reflect.ValueOf(fieldName)
+		if nameVal.Type().AssignableTo(receiver.Type().Key()) {
+			if hasArgs {
+				s.errorf("%s is not a method but has arguments", fieldName)
+			}
+			return receiver.MapIndex(nameVal)
+		}
+	}
+	s.errorf("can't evaluate field %s in type %s", fieldName, typ)
+	panic("not reached")
+}
+
+var (
+	errorType       = reflect.TypeOf((*error)(nil)).Elem()
+	fmtStringerType = reflect.TypeOf((*fmt.Stringer)(nil)).Elem()
+)
+
+// evalCall executes a function or method call. If it's a method, fun already has the receiver bound, so
+// it looks just like a function call.  The arg list, if non-nil, includes (in the manner of the shell), arg[0]
+// as the function itself.
+func (s *state) evalCall(dot, fun reflect.Value, node parse.Node, name string, args []parse.Node, final reflect.Value) reflect.Value {
+	if args != nil {
+		args = args[1:] // Zeroth arg is function name/node; not passed to function.
+	}
+	typ := fun.Type()
+	numIn := len(args)
+	if final.IsValid() {
+		numIn++
+	}
+	numFixed := len(args)
+	if typ.IsVariadic() {
+		numFixed = typ.NumIn() - 1 // last arg is the variadic one.
+		if numIn < numFixed {
+			s.errorf("wrong number of args for %s: want at least %d got %d", name, typ.NumIn()-1, len(args))
+		}
+	} else if numIn < typ.NumIn()-1 || !typ.IsVariadic() && numIn != typ.NumIn() {
+		s.errorf("wrong number of args for %s: want %d got %d", name, typ.NumIn(), len(args))
+	}
+	if !goodFunc(typ) {
+		// TODO: This could still be a confusing error; maybe goodFunc should provide info.
+		s.errorf("can't call method/function %q with %d results", name, typ.NumOut())
+	}
+	// Build the arg list.
+	argv := make([]reflect.Value, numIn)
+	// Args must be evaluated. Fixed args first.
+	i := 0
+	for ; i < numFixed && i < len(args); i++ {
+		argv[i] = s.evalArg(dot, typ.In(i), args[i])
+	}
+	// Now the ... args.
+	if typ.IsVariadic() {
+		argType := typ.In(typ.NumIn() - 1).Elem() // Argument is a slice.
+		for ; i < len(args); i++ {
+			argv[i] = s.evalArg(dot, argType, args[i])
+		}
+	}
+	// Add final value if necessary.
+	if final.IsValid() {
+		t := typ.In(typ.NumIn() - 1)
+		if typ.IsVariadic() {
+			t = t.Elem()
+		}
+		argv[i] = s.validateType(final, t)
+	}
+	result := fun.Call(argv)
+	// If we have an error that is not nil, stop execution and return that error to the caller.
+	if len(result) == 2 && !result[1].IsNil() {
+		s.at(node)
+		s.errorf("error calling %s: %s", name, result[1].Interface().(error))
+	}
+	return result[0]
+}
+
+// canBeNil reports whether an untyped nil can be assigned to the type. See reflect.Zero.
+func canBeNil(typ reflect.Type) bool {
+	switch typ.Kind() {
+	case reflect.Chan, reflect.Func, reflect.Interface, reflect.Map, reflect.Ptr, reflect.Slice:
+		return true
+	}
+	return false
+}
+
+// validateType guarantees that the value is valid and assignable to the type.
+func (s *state) validateType(value reflect.Value, typ reflect.Type) reflect.Value {
+	if !value.IsValid() {
+		if typ == nil || canBeNil(typ) {
+			// An untyped nil interface{}. Accept as a proper nil value.
+			return reflect.Zero(typ)
+		}
+		s.errorf("invalid value; expected %s", typ)
+	}
+	if typ != nil && !value.Type().AssignableTo(typ) {
+		if value.Kind() == reflect.Interface && !value.IsNil() {
+			value = value.Elem()
+			if value.Type().AssignableTo(typ) {
+				return value
+			}
+			// fallthrough
+		}
+		// Does one dereference or indirection work? We could do more, as we
+		// do with method receivers, but that gets messy and method receivers
+		// are much more constrained, so it makes more sense there than here.
+		// Besides, one is almost always all you need.
+		switch {
+		case value.Kind() == reflect.Ptr && value.Type().Elem().AssignableTo(typ):
+			value = value.Elem()
+			if !value.IsValid() {
+				s.errorf("dereference of nil pointer of type %s", typ)
+			}
+		case reflect.PtrTo(value.Type()).AssignableTo(typ) && value.CanAddr():
+			value = value.Addr()
+		default:
+			s.errorf("wrong type for value; expected %s; got %s", typ, value.Type())
+		}
+	}
+	return value
+}
+
+func (s *state) evalArg(dot reflect.Value, typ reflect.Type, n parse.Node) reflect.Value {
+	s.at(n)
+	switch arg := n.(type) {
+	case *parse.DotNode:
+		return s.validateType(dot, typ)
+	case *parse.NilNode:
+		if canBeNil(typ) {
+			return reflect.Zero(typ)
+		}
+		s.errorf("cannot assign nil to %s", typ)
+	case *parse.FieldNode:
+		return s.validateType(s.evalFieldNode(dot, arg, []parse.Node{n}, zero), typ)
+	case *parse.VariableNode:
+		return s.validateType(s.evalVariableNode(dot, arg, nil, zero), typ)
+	case *parse.PipeNode:
+		return s.validateType(s.evalPipeline(dot, arg), typ)
+	case *parse.IdentifierNode:
+		return s.evalFunction(dot, arg, arg, nil, zero)
+	case *parse.ChainNode:
+		return s.validateType(s.evalChainNode(dot, arg, nil, zero), typ)
+	}
+	switch typ.Kind() {
+	case reflect.Bool:
+		return s.evalBool(typ, n)
+	case reflect.Complex64, reflect.Complex128:
+		return s.evalComplex(typ, n)
+	case reflect.Float32, reflect.Float64:
+		return s.evalFloat(typ, n)
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		return s.evalInteger(typ, n)
+	case reflect.Interface:
+		if typ.NumMethod() == 0 {
+			return s.evalEmptyInterface(dot, n)
+		}
+	case reflect.String:
+		return s.evalString(typ, n)
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+		return s.evalUnsignedInteger(typ, n)
+	}
+	s.errorf("can't handle %s for arg of type %s", n, typ)
+	panic("not reached")
+}
+
+func (s *state) evalBool(typ reflect.Type, n parse.Node) reflect.Value {
+	s.at(n)
+	if n, ok := n.(*parse.BoolNode); ok {
+		value := reflect.New(typ).Elem()
+		value.SetBool(n.True)
+		return value
+	}
+	s.errorf("expected bool; found %s", n)
+	panic("not reached")
+}
+
+func (s *state) evalString(typ reflect.Type, n parse.Node) reflect.Value {
+	s.at(n)
+	if n, ok := n.(*parse.StringNode); ok {
+		value := reflect.New(typ).Elem()
+		value.SetString(n.Text)
+		return value
+	}
+	s.errorf("expected string; found %s", n)
+	panic("not reached")
+}
+
+func (s *state) evalInteger(typ reflect.Type, n parse.Node) reflect.Value {
+	s.at(n)
+	if n, ok := n.(*parse.NumberNode); ok && n.IsInt {
+		value := reflect.New(typ).Elem()
+		value.SetInt(n.Int64)
+		return value
+	}
+	s.errorf("expected integer; found %s", n)
+	panic("not reached")
+}
+
+func (s *state) evalUnsignedInteger(typ reflect.Type, n parse.Node) reflect.Value {
+	s.at(n)
+	if n, ok := n.(*parse.NumberNode); ok && n.IsUint {
+		value := reflect.New(typ).Elem()
+		value.SetUint(n.Uint64)
+		return value
+	}
+	s.errorf("expected unsigned integer; found %s", n)
+	panic("not reached")
+}
+
+func (s *state) evalFloat(typ reflect.Type, n parse.Node) reflect.Value {
+	s.at(n)
+	if n, ok := n.(*parse.NumberNode); ok && n.IsFloat {
+		value := reflect.New(typ).Elem()
+		value.SetFloat(n.Float64)
+		return value
+	}
+	s.errorf("expected float; found %s", n)
+	panic("not reached")
+}
+
+func (s *state) evalComplex(typ reflect.Type, n parse.Node) reflect.Value {
+	if n, ok := n.(*parse.NumberNode); ok && n.IsComplex {
+		value := reflect.New(typ).Elem()
+		value.SetComplex(n.Complex128)
+		return value
+	}
+	s.errorf("expected complex; found %s", n)
+	panic("not reached")
+}
+
+func (s *state) evalEmptyInterface(dot reflect.Value, n parse.Node) reflect.Value {
+	s.at(n)
+	switch n := n.(type) {
+	case *parse.BoolNode:
+		return reflect.ValueOf(n.True)
+	case *parse.DotNode:
+		return dot
+	case *parse.FieldNode:
+		return s.evalFieldNode(dot, n, nil, zero)
+	case *parse.IdentifierNode:
+		return s.evalFunction(dot, n, n, nil, zero)
+	case *parse.NilNode:
+		// NilNode is handled in evalArg, the only place that calls here.
+		s.errorf("evalEmptyInterface: nil (can't happen)")
+	case *parse.NumberNode:
+		return s.idealConstant(n)
+	case *parse.StringNode:
+		return reflect.ValueOf(n.Text)
+	case *parse.VariableNode:
+		return s.evalVariableNode(dot, n, nil, zero)
+	case *parse.PipeNode:
+		return s.evalPipeline(dot, n)
+	}
+	s.errorf("can't handle assignment of %s to empty interface argument", n)
+	panic("not reached")
+}
+
+// indirect returns the item at the end of indirection, and a bool to indicate if it's nil.
+// We indirect through pointers and empty interfaces (only) because
+// non-empty interfaces have methods we might need.
+func indirect(v reflect.Value) (rv reflect.Value, isNil bool) {
+	for ; v.Kind() == reflect.Ptr || v.Kind() == reflect.Interface; v = v.Elem() {
+		if v.IsNil() {
+			return v, true
+		}
+		if v.Kind() == reflect.Interface && v.NumMethod() > 0 {
+			break
+		}
+	}
+	return v, false
+}
+
+// printValue writes the textual representation of the value to the output of
+// the template.
+func (s *state) printValue(n parse.Node, v reflect.Value) {
+	s.at(n)
+	iface, ok := printableValue(v)
+	if !ok {
+		s.errorf("can't print %s of type %s", n, v.Type())
+	}
+	fmt.Fprint(s.wr, iface)
+}
+
+// printableValue returns the, possibly indirected, interface value inside v that
+// is best for a call to formatted printer.
+func printableValue(v reflect.Value) (interface{}, bool) {
+	if v.Kind() == reflect.Ptr {
+		v, _ = indirect(v) // fmt.Fprint handles nil.
+	}
+	if !v.IsValid() {
+		return "<no value>", true
+	}
+
+	if !v.Type().Implements(errorType) && !v.Type().Implements(fmtStringerType) {
+		if v.CanAddr() && (reflect.PtrTo(v.Type()).Implements(errorType) || reflect.PtrTo(v.Type()).Implements(fmtStringerType)) {
+			v = v.Addr()
+		} else {
+			switch v.Kind() {
+			case reflect.Chan, reflect.Func:
+				return nil, false
+			}
+		}
+	}
+	return v.Interface(), true
+}
+
+// Types to help sort the keys in a map for reproducible output.
+
+type rvs []reflect.Value
+
+func (x rvs) Len() int      { return len(x) }
+func (x rvs) Swap(i, j int) { x[i], x[j] = x[j], x[i] }
+
+type rvInts struct{ rvs }
+
+func (x rvInts) Less(i, j int) bool { return x.rvs[i].Int() < x.rvs[j].Int() }
+
+type rvUints struct{ rvs }
+
+func (x rvUints) Less(i, j int) bool { return x.rvs[i].Uint() < x.rvs[j].Uint() }
+
+type rvFloats struct{ rvs }
+
+func (x rvFloats) Less(i, j int) bool { return x.rvs[i].Float() < x.rvs[j].Float() }
+
+type rvStrings struct{ rvs }
+
+func (x rvStrings) Less(i, j int) bool { return x.rvs[i].String() < x.rvs[j].String() }
+
+// sortKeys sorts (if it can) the slice of reflect.Values, which is a slice of map keys.
+func sortKeys(v []reflect.Value) []reflect.Value {
+	if len(v) <= 1 {
+		return v
+	}
+	switch v[0].Kind() {
+	case reflect.Float32, reflect.Float64:
+		sort.Sort(rvFloats{v})
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		sort.Sort(rvInts{v})
+	case reflect.String:
+		sort.Sort(rvStrings{v})
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+		sort.Sort(rvUints{v})
+	}
+	return v
+}

vendor/github.com/alecthomas/template/funcs.go

@@ -0,0 +1,598 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package template
+
+import (
+	"bytes"
+	"errors"
+	"fmt"
+	"io"
+	"net/url"
+	"reflect"
+	"strings"
+	"unicode"
+	"unicode/utf8"
+)
+
+// FuncMap is the type of the map defining the mapping from names to functions.
+// Each function must have either a single return value, or two return values of
+// which the second has type error. In that case, if the second (error)
+// return value evaluates to non-nil during execution, execution terminates and
+// Execute returns that error.
+type FuncMap map[string]interface{}
+
+var builtins = FuncMap{
+	"and":      and,
+	"call":     call,
+	"html":     HTMLEscaper,
+	"index":    index,
+	"js":       JSEscaper,
+	"len":      length,
+	"not":      not,
+	"or":       or,
+	"print":    fmt.Sprint,
+	"printf":   fmt.Sprintf,
+	"println":  fmt.Sprintln,
+	"urlquery": URLQueryEscaper,
+
+	// Comparisons
+	"eq": eq, // ==
+	"ge": ge, // >=
+	"gt": gt, // >
+	"le": le, // <=
+	"lt": lt, // <
+	"ne": ne, // !=
+}
+
+var builtinFuncs = createValueFuncs(builtins)
+
+// createValueFuncs turns a FuncMap into a map[string]reflect.Value
+func createValueFuncs(funcMap FuncMap) map[string]reflect.Value {
+	m := make(map[string]reflect.Value)
+	addValueFuncs(m, funcMap)
+	return m
+}
+
+// addValueFuncs adds to values the functions in funcs, converting them to reflect.Values.
+func addValueFuncs(out map[string]reflect.Value, in FuncMap) {
+	for name, fn := range in {
+		v := reflect.ValueOf(fn)
+		if v.Kind() != reflect.Func {
+			panic("value for " + name + " not a function")
+		}
+		if !goodFunc(v.Type()) {
+			panic(fmt.Errorf("can't install method/function %q with %d results", name, v.Type().NumOut()))
+		}
+		out[name] = v
+	}
+}
+
+// addFuncs adds to values the functions in funcs. It does no checking of the input -
+// call addValueFuncs first.
+func addFuncs(out, in FuncMap) {
+	for name, fn := range in {
+		out[name] = fn
+	}
+}
+
+// goodFunc checks that the function or method has the right result signature.
+func goodFunc(typ reflect.Type) bool {
+	// We allow functions with 1 result or 2 results where the second is an error.
+	switch {
+	case typ.NumOut() == 1:
+		return true
+	case typ.NumOut() == 2 && typ.Out(1) == errorType:
+		return true
+	}
+	return false
+}
+
+// findFunction looks for a function in the template, and global map.
+func findFunction(name string, tmpl *Template) (reflect.Value, bool) {
+	if tmpl != nil && tmpl.common != nil {
+		if fn := tmpl.execFuncs[name]; fn.IsValid() {
+			return fn, true
+		}
+	}
+	if fn := builtinFuncs[name]; fn.IsValid() {
+		return fn, true
+	}
+	return reflect.Value{}, false
+}
+
+// Indexing.
+
+// index returns the result of indexing its first argument by the following
+// arguments.  Thus "index x 1 2 3" is, in Go syntax, x[1][2][3]. Each
+// indexed item must be a map, slice, or array.
+func index(item interface{}, indices ...interface{}) (interface{}, error) {
+	v := reflect.ValueOf(item)
+	for _, i := range indices {
+		index := reflect.ValueOf(i)
+		var isNil bool
+		if v, isNil = indirect(v); isNil {
+			return nil, fmt.Errorf("index of nil pointer")
+		}
+		switch v.Kind() {
+		case reflect.Array, reflect.Slice, reflect.String:
+			var x int64
+			switch index.Kind() {
+			case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+				x = index.Int()
+			case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+				x = int64(index.Uint())
+			default:
+				return nil, fmt.Errorf("cannot index slice/array with type %s", index.Type())
+			}
+			if x < 0 || x >= int64(v.Len()) {
+				return nil, fmt.Errorf("index out of range: %d", x)
+			}
+			v = v.Index(int(x))
+		case reflect.Map:
+			if !index.IsValid() {
+				index = reflect.Zero(v.Type().Key())
+			}
+			if !index.Type().AssignableTo(v.Type().Key()) {
+				return nil, fmt.Errorf("%s is not index type for %s", index.Type(), v.Type())
+			}
+			if x := v.MapIndex(index); x.IsValid() {
+				v = x
+			} else {
+				v = reflect.Zero(v.Type().Elem())
+			}
+		default:
+			return nil, fmt.Errorf("can't index item of type %s", v.Type())
+		}
+	}
+	return v.Interface(), nil
+}
+
+// Length
+
+// length returns the length of the item, with an error if it has no defined length.
+func length(item interface{}) (int, error) {
+	v, isNil := indirect(reflect.ValueOf(item))
+	if isNil {
+		return 0, fmt.Errorf("len of nil pointer")
+	}
+	switch v.Kind() {
+	case reflect.Array, reflect.Chan, reflect.Map, reflect.Slice, reflect.String:
+		return v.Len(), nil
+	}
+	return 0, fmt.Errorf("len of type %s", v.Type())
+}
+
+// Function invocation
+
+// call returns the result of evaluating the first argument as a function.
+// The function must return 1 result, or 2 results, the second of which is an error.
+func call(fn interface{}, args ...interface{}) (interface{}, error) {
+	v := reflect.ValueOf(fn)
+	typ := v.Type()
+	if typ.Kind() != reflect.Func {
+		return nil, fmt.Errorf("non-function of type %s", typ)
+	}
+	if !goodFunc(typ) {
+		return nil, fmt.Errorf("function called with %d args; should be 1 or 2", typ.NumOut())
+	}
+	numIn := typ.NumIn()
+	var dddType reflect.Type
+	if typ.IsVariadic() {
+		if len(args) < numIn-1 {
+			return nil, fmt.Errorf("wrong number of args: got %d want at least %d", len(args), numIn-1)
+		}
+		dddType = typ.In(numIn - 1).Elem()
+	} else {
+		if len(args) != numIn {
+			return nil, fmt.Errorf("wrong number of args: got %d want %d", len(args), numIn)
+		}
+	}
+	argv := make([]reflect.Value, len(args))
+	for i, arg := range args {
+		value := reflect.ValueOf(arg)
+		// Compute the expected type. Clumsy because of variadics.
+		var argType reflect.Type
+		if !typ.IsVariadic() || i < numIn-1 {
+			argType = typ.In(i)
+		} else {
+			argType = dddType
+		}
+		if !value.IsValid() && canBeNil(argType) {
+			value = reflect.Zero(argType)
+		}
+		if !value.Type().AssignableTo(argType) {
+			return nil, fmt.Errorf("arg %d has type %s; should be %s", i, value.Type(), argType)
+		}
+		argv[i] = value
+	}
+	result := v.Call(argv)
+	if len(result) == 2 && !result[1].IsNil() {
+		return result[0].Interface(), result[1].Interface().(error)
+	}
+	return result[0].Interface(), nil
+}
+
+// Boolean logic.
+
+func truth(a interface{}) bool {
+	t, _ := isTrue(reflect.ValueOf(a))
+	return t
+}
+
+// and computes the Boolean AND of its arguments, returning
+// the first false argument it encounters, or the last argument.
+func and(arg0 interface{}, args ...interface{}) interface{} {
+	if !truth(arg0) {
+		return arg0
+	}
+	for i := range args {
+		arg0 = args[i]
+		if !truth(arg0) {
+			break
+		}
+	}
+	return arg0
+}
+
+// or computes the Boolean OR of its arguments, returning
+// the first true argument it encounters, or the last argument.
+func or(arg0 interface{}, args ...interface{}) interface{} {
+	if truth(arg0) {
+		return arg0
+	}
+	for i := range args {
+		arg0 = args[i]
+		if truth(arg0) {
+			break
+		}
+	}
+	return arg0
+}
+
+// not returns the Boolean negation of its argument.
+func not(arg interface{}) (truth bool) {
+	truth, _ = isTrue(reflect.ValueOf(arg))
+	return !truth
+}
+
+// Comparison.
+
+// TODO: Perhaps allow comparison between signed and unsigned integers.
+
+var (
+	errBadComparisonType = errors.New("invalid type for comparison")
+	errBadComparison     = errors.New("incompatible types for comparison")
+	errNoComparison      = errors.New("missing argument for comparison")
+)
+
+type kind int
+
+const (
+	invalidKind kind = iota
+	boolKind
+	complexKind
+	intKind
+	floatKind
+	integerKind
+	stringKind
+	uintKind
+)
+
+func basicKind(v reflect.Value) (kind, error) {
+	switch v.Kind() {
+	case reflect.Bool:
+		return boolKind, nil
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		return intKind, nil
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+		return uintKind, nil
+	case reflect.Float32, reflect.Float64:
+		return floatKind, nil
+	case reflect.Complex64, reflect.Complex128:
+		return complexKind, nil
+	case reflect.String:
+		return stringKind, nil
+	}
+	return invalidKind, errBadComparisonType
+}
+
+// eq evaluates the comparison a == b || a == c || ...
+func eq(arg1 interface{}, arg2 ...interface{}) (bool, error) {
+	v1 := reflect.ValueOf(arg1)
+	k1, err := basicKind(v1)
+	if err != nil {
+		return false, err
+	}
+	if len(arg2) == 0 {
+		return false, errNoComparison
+	}
+	for _, arg := range arg2 {
+		v2 := reflect.ValueOf(arg)
+		k2, err := basicKind(v2)
+		if err != nil {
+			return false, err
+		}
+		truth := false
+		if k1 != k2 {
+			// Special case: Can compare integer values regardless of type's sign.
+			switch {
+			case k1 == intKind && k2 == uintKind:
+				truth = v1.Int() >= 0 && uint64(v1.Int()) == v2.Uint()
+			case k1 == uintKind && k2 == intKind:
+				truth = v2.Int() >= 0 && v1.Uint() == uint64(v2.Int())
+			default:
+				return false, errBadComparison
+			}
+		} else {
+			switch k1 {
+			case boolKind:
+				truth = v1.Bool() == v2.Bool()
+			case complexKind:
+				truth = v1.Complex() == v2.Complex()
+			case floatKind:
+				truth = v1.Float() == v2.Float()
+			case intKind:
+				truth = v1.Int() == v2.Int()
+			case stringKind:
+				truth = v1.String() == v2.String()
+			case uintKind:
+				truth = v1.Uint() == v2.Uint()
+			default:
+				panic("invalid kind")
+			}
+		}
+		if truth {
+			return true, nil
+		}
+	}
+	return false, nil
+}
+
+// ne evaluates the comparison a != b.
+func ne(arg1, arg2 interface{}) (bool, error) {
+	// != is the inverse of ==.
+	equal, err := eq(arg1, arg2)
+	return !equal, err
+}
+
+// lt evaluates the comparison a < b.
+func lt(arg1, arg2 interface{}) (bool, error) {
+	v1 := reflect.ValueOf(arg1)
+	k1, err := basicKind(v1)
+	if err != nil {
+		return false, err
+	}
+	v2 := reflect.ValueOf(arg2)
+	k2, err := basicKind(v2)
+	if err != nil {
+		return false, err
+	}
+	truth := false
+	if k1 != k2 {
+		// Special case: Can compare integer values regardless of type's sign.
+		switch {
+		case k1 == intKind && k2 == uintKind:
+			truth = v1.Int() < 0 || uint64(v1.Int()) < v2.Uint()
+		case k1 == uintKind && k2 == intKind:
+			truth = v2.Int() >= 0 && v1.Uint() < uint64(v2.Int())
+		default:
+			return false, errBadComparison
+		}
+	} else {
+		switch k1 {
+		case boolKind, complexKind:
+			return false, errBadComparisonType
+		case floatKind:
+			truth = v1.Float() < v2.Float()
+		case intKind:
+			truth = v1.Int() < v2.Int()
+		case stringKind:
+			truth = v1.String() < v2.String()
+		case uintKind:
+			truth = v1.Uint() < v2.Uint()
+		default:
+			panic("invalid kind")
+		}
+	}
+	return truth, nil
+}
+
+// le evaluates the comparison <= b.
+func le(arg1, arg2 interface{}) (bool, error) {
+	// <= is < or ==.
+	lessThan, err := lt(arg1, arg2)
+	if lessThan || err != nil {
+		return lessThan, err
+	}
+	return eq(arg1, arg2)
+}
+
+// gt evaluates the comparison a > b.
+func gt(arg1, arg2 interface{}) (bool, error) {
+	// > is the inverse of <=.
+	lessOrEqual, err := le(arg1, arg2)
+	if err != nil {
+		return false, err
+	}
+	return !lessOrEqual, nil
+}
+
+// ge evaluates the comparison a >= b.
+func ge(arg1, arg2 interface{}) (bool, error) {
+	// >= is the inverse of <.
+	lessThan, err := lt(arg1, arg2)
+	if err != nil {
+		return false, err
+	}
+	return !lessThan, nil
+}
+
+// HTML escaping.
+
+var (
+	htmlQuot = []byte("&#34;") // shorter than "&quot;"
+	htmlApos = []byte("&#39;") // shorter than "&apos;" and apos was not in HTML until HTML5
+	htmlAmp  = []byte("&amp;")
+	htmlLt   = []byte("&lt;")
+	htmlGt   = []byte("&gt;")
+)
+
+// HTMLEscape writes to w the escaped HTML equivalent of the plain text data b.
+func HTMLEscape(w io.Writer, b []byte) {
+	last := 0
+	for i, c := range b {
+		var html []byte
+		switch c {
+		case '"':
+			html = htmlQuot
+		case '\'':
+			html = htmlApos
+		case '&':
+			html = htmlAmp
+		case '<':
+			html = htmlLt
+		case '>':
+			html = htmlGt
+		default:
+			continue
+		}
+		w.Write(b[last:i])
+		w.Write(html)
+		last = i + 1
+	}
+	w.Write(b[last:])
+}
+
+// HTMLEscapeString returns the escaped HTML equivalent of the plain text data s.
+func HTMLEscapeString(s string) string {
+	// Avoid allocation if we can.
+	if strings.IndexAny(s, `'"&<>`) < 0 {
+		return s
+	}
+	var b bytes.Buffer
+	HTMLEscape(&b, []byte(s))
+	return b.String()
+}
+
+// HTMLEscaper returns the escaped HTML equivalent of the textual
+// representation of its arguments.
+func HTMLEscaper(args ...interface{}) string {
+	return HTMLEscapeString(evalArgs(args))
+}
+
+// JavaScript escaping.
+
+var (
+	jsLowUni = []byte(`\u00`)
+	hex      = []byte("0123456789ABCDEF")
+
+	jsBackslash = []byte(`\\`)
+	jsApos      = []byte(`\'`)
+	jsQuot      = []byte(`\"`)
+	jsLt        = []byte(`\x3C`)
+	jsGt        = []byte(`\x3E`)
+)
+
+// JSEscape writes to w the escaped JavaScript equivalent of the plain text data b.
+func JSEscape(w io.Writer, b []byte) {
+	last := 0
+	for i := 0; i < len(b); i++ {
+		c := b[i]
+
+		if !jsIsSpecial(rune(c)) {
+			// fast path: nothing to do
+			continue
+		}
+		w.Write(b[last:i])
+
+		if c < utf8.RuneSelf {
+			// Quotes, slashes and angle brackets get quoted.
+			// Control characters get written as \u00XX.
+			switch c {
+			case '\\':
+				w.Write(jsBackslash)
+			case '\'':
+				w.Write(jsApos)
+			case '"':
+				w.Write(jsQuot)
+			case '<':
+				w.Write(jsLt)
+			case '>':
+				w.Write(jsGt)
+			default:
+				w.Write(jsLowUni)
+				t, b := c>>4, c&0x0f
+				w.Write(hex[t : t+1])
+				w.Write(hex[b : b+1])
+			}
+		} else {
+			// Unicode rune.
+			r, size := utf8.DecodeRune(b[i:])
+			if unicode.IsPrint(r) {
+				w.Write(b[i : i+size])
+			} else {
+				fmt.Fprintf(w, "\\u%04X", r)
+			}
+			i += size - 1
+		}
+		last = i + 1
+	}
+	w.Write(b[last:])
+}
+
+// JSEscapeString returns the escaped JavaScript equivalent of the plain text data s.
+func JSEscapeString(s string) string {
+	// Avoid allocation if we can.
+	if strings.IndexFunc(s, jsIsSpecial) < 0 {
+		return s
+	}
+	var b bytes.Buffer
+	JSEscape(&b, []byte(s))
+	return b.String()
+}
+
+func jsIsSpecial(r rune) bool {
+	switch r {
+	case '\\', '\'', '"', '<', '>':
+		return true
+	}
+	return r < ' ' || utf8.RuneSelf <= r
+}
+
+// JSEscaper returns the escaped JavaScript equivalent of the textual
+// representation of its arguments.
+func JSEscaper(args ...interface{}) string {
+	return JSEscapeString(evalArgs(args))
+}
+
+// URLQueryEscaper returns the escaped value of the textual representation of
+// its arguments in a form suitable for embedding in a URL query.
+func URLQueryEscaper(args ...interface{}) string {
+	return url.QueryEscape(evalArgs(args))
+}
+
+// evalArgs formats the list of arguments into a string. It is therefore equivalent to
+//	fmt.Sprint(args...)
+// except that each argument is indirected (if a pointer), as required,
+// using the same rules as the default string evaluation during template
+// execution.
+func evalArgs(args []interface{}) string {
+	ok := false
+	var s string
+	// Fast path for simple common case.
+	if len(args) == 1 {
+		s, ok = args[0].(string)
+	}
+	if !ok {
+		for i, arg := range args {
+			a, ok := printableValue(reflect.ValueOf(arg))
+			if ok {
+				args[i] = a
+			} // else left fmt do its thing
+		}
+		s = fmt.Sprint(args...)
+	}
+	return s
+}

vendor/github.com/alecthomas/template/helper.go

@@ -0,0 +1,108 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Helper functions to make constructing templates easier.
+
+package template
+
+import (
+	"fmt"
+	"io/ioutil"
+	"path/filepath"
+)
+
+// Functions and methods to parse templates.
+
+// Must is a helper that wraps a call to a function returning (*Template, error)
+// and panics if the error is non-nil. It is intended for use in variable
+// initializations such as
+//	var t = template.Must(template.New("name").Parse("text"))
+func Must(t *Template, err error) *Template {
+	if err != nil {
+		panic(err)
+	}
+	return t
+}
+
+// ParseFiles creates a new Template and parses the template definitions from
+// the named files. The returned template's name will have the (base) name and
+// (parsed) contents of the first file. There must be at least one file.
+// If an error occurs, parsing stops and the returned *Template is nil.
+func ParseFiles(filenames ...string) (*Template, error) {
+	return parseFiles(nil, filenames...)
+}
+
+// ParseFiles parses the named files and associates the resulting templates with
+// t. If an error occurs, parsing stops and the returned template is nil;
+// otherwise it is t. There must be at least one file.
+func (t *Template) ParseFiles(filenames ...string) (*Template, error) {
+	return parseFiles(t, filenames...)
+}
+
+// parseFiles is the helper for the method and function. If the argument
+// template is nil, it is created from the first file.
+func parseFiles(t *Template, filenames ...string) (*Template, error) {
+	if len(filenames) == 0 {
+		// Not really a problem, but be consistent.
+		return nil, fmt.Errorf("template: no files named in call to ParseFiles")
+	}
+	for _, filename := range filenames {
+		b, err := ioutil.ReadFile(filename)
+		if err != nil {
+			return nil, err
+		}
+		s := string(b)
+		name := filepath.Base(filename)
+		// First template becomes return value if not already defined,
+		// and we use that one for subsequent New calls to associate
+		// all the templates together. Also, if this file has the same name
+		// as t, this file becomes the contents of t, so
+		//  t, err := New(name).Funcs(xxx).ParseFiles(name)
+		// works. Otherwise we create a new template associated with t.
+		var tmpl *Template
+		if t == nil {
+			t = New(name)
+		}
+		if name == t.Name() {
+			tmpl = t
+		} else {
+			tmpl = t.New(name)
+		}
+		_, err = tmpl.Parse(s)
+		if err != nil {
+			return nil, err
+		}
+	}
+	return t, nil
+}
+
+// ParseGlob creates a new Template and parses the template definitions from the
+// files identified by the pattern, which must match at least one file. The
+// returned template will have the (base) name and (parsed) contents of the
+// first file matched by the pattern. ParseGlob is equivalent to calling
+// ParseFiles with the list of files matched by the pattern.
+func ParseGlob(pattern string) (*Template, error) {
+	return parseGlob(nil, pattern)
+}
+
+// ParseGlob parses the template definitions in the files identified by the
+// pattern and associates the resulting templates with t. The pattern is
+// processed by filepath.Glob and must match at least one file. ParseGlob is
+// equivalent to calling t.ParseFiles with the list of files matched by the
+// pattern.
+func (t *Template) ParseGlob(pattern string) (*Template, error) {
+	return parseGlob(t, pattern)
+}
+
+// parseGlob is the implementation of the function and method ParseGlob.
+func parseGlob(t *Template, pattern string) (*Template, error) {
+	filenames, err := filepath.Glob(pattern)
+	if err != nil {
+		return nil, err
+	}
+	if len(filenames) == 0 {
+		return nil, fmt.Errorf("template: pattern matches no files: %#q", pattern)
+	}
+	return parseFiles(t, filenames...)
+}

vendor/github.com/alecthomas/template/multi_test.go

@@ -0,0 +1,293 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package template
+
+// Tests for mulitple-template parsing and execution.
+
+import (
+	"bytes"
+	"fmt"
+	"strings"
+	"testing"
+
+	"github.com/alecthomas/template/parse"
+)
+
+const (
+	noError  = true
+	hasError = false
+)
+
+type multiParseTest struct {
+	name    string
+	input   string
+	ok      bool
+	names   []string
+	results []string
+}
+
+var multiParseTests = []multiParseTest{
+	{"empty", "", noError,
+		nil,
+		nil},
+	{"one", `{{define "foo"}} FOO {{end}}`, noError,
+		[]string{"foo"},
+		[]string{" FOO "}},
+	{"two", `{{define "foo"}} FOO {{end}}{{define "bar"}} BAR {{end}}`, noError,
+		[]string{"foo", "bar"},
+		[]string{" FOO ", " BAR "}},
+	// errors
+	{"missing end", `{{define "foo"}} FOO `, hasError,
+		nil,
+		nil},
+	{"malformed name", `{{define "foo}} FOO `, hasError,
+		nil,
+		nil},
+}
+
+func TestMultiParse(t *testing.T) {
+	for _, test := range multiParseTests {
+		template, err := New("root").Parse(test.input)
+		switch {
+		case err == nil && !test.ok:
+			t.Errorf("%q: expected error; got none", test.name)
+			continue
+		case err != nil && test.ok:
+			t.Errorf("%q: unexpected error: %v", test.name, err)
+			continue
+		case err != nil && !test.ok:
+			// expected error, got one
+			if *debug {
+				fmt.Printf("%s: %s\n\t%s\n", test.name, test.input, err)
+			}
+			continue
+		}
+		if template == nil {
+			continue
+		}
+		if len(template.tmpl) != len(test.names)+1 { // +1 for root
+			t.Errorf("%s: wrong number of templates; wanted %d got %d", test.name, len(test.names), len(template.tmpl))
+			continue
+		}
+		for i, name := range test.names {
+			tmpl, ok := template.tmpl[name]
+			if !ok {
+				t.Errorf("%s: can't find template %q", test.name, name)
+				continue
+			}
+			result := tmpl.Root.String()
+			if result != test.results[i] {
+				t.Errorf("%s=(%q): got\n\t%v\nexpected\n\t%v", test.name, test.input, result, test.results[i])
+			}
+		}
+	}
+}
+
+var multiExecTests = []execTest{
+	{"empty", "", "", nil, true},
+	{"text", "some text", "some text", nil, true},
+	{"invoke x", `{{template "x" .SI}}`, "TEXT", tVal, true},
+	{"invoke x no args", `{{template "x"}}`, "TEXT", tVal, true},
+	{"invoke dot int", `{{template "dot" .I}}`, "17", tVal, true},
+	{"invoke dot []int", `{{template "dot" .SI}}`, "[3 4 5]", tVal, true},
+	{"invoke dotV", `{{template "dotV" .U}}`, "v", tVal, true},
+	{"invoke nested int", `{{template "nested" .I}}`, "17", tVal, true},
+	{"variable declared by template", `{{template "nested" $x:=.SI}},{{index $x 1}}`, "[3 4 5],4", tVal, true},
+
+	// User-defined function: test argument evaluator.
+	{"testFunc literal", `{{oneArg "joe"}}`, "oneArg=joe", tVal, true},
+	{"testFunc .", `{{oneArg .}}`, "oneArg=joe", "joe", true},
+}
+
+// These strings are also in testdata/*.
+const multiText1 = `
+	{{define "x"}}TEXT{{end}}
+	{{define "dotV"}}{{.V}}{{end}}
+`
+
+const multiText2 = `
+	{{define "dot"}}{{.}}{{end}}
+	{{define "nested"}}{{template "dot" .}}{{end}}
+`
+
+func TestMultiExecute(t *testing.T) {
+	// Declare a couple of templates first.
+	template, err := New("root").Parse(multiText1)
+	if err != nil {
+		t.Fatalf("parse error for 1: %s", err)
+	}
+	_, err = template.Parse(multiText2)
+	if err != nil {
+		t.Fatalf("parse error for 2: %s", err)
+	}
+	testExecute(multiExecTests, template, t)
+}
+
+func TestParseFiles(t *testing.T) {
+	_, err := ParseFiles("DOES NOT EXIST")
+	if err == nil {
+		t.Error("expected error for non-existent file; got none")
+	}
+	template := New("root")
+	_, err = template.ParseFiles("testdata/file1.tmpl", "testdata/file2.tmpl")
+	if err != nil {
+		t.Fatalf("error parsing files: %v", err)
+	}
+	testExecute(multiExecTests, template, t)
+}
+
+func TestParseGlob(t *testing.T) {
+	_, err := ParseGlob("DOES NOT EXIST")
+	if err == nil {
+		t.Error("expected error for non-existent file; got none")
+	}
+	_, err = New("error").ParseGlob("[x")
+	if err == nil {
+		t.Error("expected error for bad pattern; got none")
+	}
+	template := New("root")
+	_, err = template.ParseGlob("testdata/file*.tmpl")
+	if err != nil {
+		t.Fatalf("error parsing files: %v", err)
+	}
+	testExecute(multiExecTests, template, t)
+}
+
+// In these tests, actual content (not just template definitions) comes from the parsed files.
+
+var templateFileExecTests = []execTest{
+	{"test", `{{template "tmpl1.tmpl"}}{{template "tmpl2.tmpl"}}`, "template1\n\ny\ntemplate2\n\nx\n", 0, true},
+}
+
+func TestParseFilesWithData(t *testing.T) {
+	template, err := New("root").ParseFiles("testdata/tmpl1.tmpl", "testdata/tmpl2.tmpl")
+	if err != nil {
+		t.Fatalf("error parsing files: %v", err)
+	}
+	testExecute(templateFileExecTests, template, t)
+}
+
+func TestParseGlobWithData(t *testing.T) {
+	template, err := New("root").ParseGlob("testdata/tmpl*.tmpl")
+	if err != nil {
+		t.Fatalf("error parsing files: %v", err)
+	}
+	testExecute(templateFileExecTests, template, t)
+}
+
+const (
+	cloneText1 = `{{define "a"}}{{template "b"}}{{template "c"}}{{end}}`
+	cloneText2 = `{{define "b"}}b{{end}}`
+	cloneText3 = `{{define "c"}}root{{end}}`
+	cloneText4 = `{{define "c"}}clone{{end}}`
+)
+
+func TestClone(t *testing.T) {
+	// Create some templates and clone the root.
+	root, err := New("root").Parse(cloneText1)
+	if err != nil {
+		t.Fatal(err)
+	}
+	_, err = root.Parse(cloneText2)
+	if err != nil {
+		t.Fatal(err)
+	}
+	clone := Must(root.Clone())
+	// Add variants to both.
+	_, err = root.Parse(cloneText3)
+	if err != nil {
+		t.Fatal(err)
+	}
+	_, err = clone.Parse(cloneText4)
+	if err != nil {
+		t.Fatal(err)
+	}
+	// Verify that the clone is self-consistent.
+	for k, v := range clone.tmpl {
+		if k == clone.name && v.tmpl[k] != clone {
+			t.Error("clone does not contain root")
+		}
+		if v != v.tmpl[v.name] {
+			t.Errorf("clone does not contain self for %q", k)
+		}
+	}
+	// Execute root.
+	var b bytes.Buffer
+	err = root.ExecuteTemplate(&b, "a", 0)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if b.String() != "broot" {
+		t.Errorf("expected %q got %q", "broot", b.String())
+	}
+	// Execute copy.
+	b.Reset()
+	err = clone.ExecuteTemplate(&b, "a", 0)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if b.String() != "bclone" {
+		t.Errorf("expected %q got %q", "bclone", b.String())
+	}
+}
+
+func TestAddParseTree(t *testing.T) {
+	// Create some templates.
+	root, err := New("root").Parse(cloneText1)
+	if err != nil {
+		t.Fatal(err)
+	}
+	_, err = root.Parse(cloneText2)
+	if err != nil {
+		t.Fatal(err)
+	}
+	// Add a new parse tree.
+	tree, err := parse.Parse("cloneText3", cloneText3, "", "", nil, builtins)
+	if err != nil {
+		t.Fatal(err)
+	}
+	added, err := root.AddParseTree("c", tree["c"])
+	// Execute.
+	var b bytes.Buffer
+	err = added.ExecuteTemplate(&b, "a", 0)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if b.String() != "broot" {
+		t.Errorf("expected %q got %q", "broot", b.String())
+	}
+}
+
+// Issue 7032
+func TestAddParseTreeToUnparsedTemplate(t *testing.T) {
+	master := "{{define \"master\"}}{{end}}"
+	tmpl := New("master")
+	tree, err := parse.Parse("master", master, "", "", nil)
+	if err != nil {
+		t.Fatalf("unexpected parse err: %v", err)
+	}
+	masterTree := tree["master"]
+	tmpl.AddParseTree("master", masterTree) // used to panic
+}
+
+func TestRedefinition(t *testing.T) {
+	var tmpl *Template
+	var err error
+	if tmpl, err = New("tmpl1").Parse(`{{define "test"}}foo{{end}}`); err != nil {
+		t.Fatalf("parse 1: %v", err)
+	}
+	if _, err = tmpl.Parse(`{{define "test"}}bar{{end}}`); err == nil {
+		t.Fatal("expected error")
+	}
+	if !strings.Contains(err.Error(), "redefinition") {
+		t.Fatalf("expected redefinition error; got %v", err)
+	}
+	if _, err = tmpl.New("tmpl2").Parse(`{{define "test"}}bar{{end}}`); err == nil {
+		t.Fatal("expected error")
+	}
+	if !strings.Contains(err.Error(), "redefinition") {
+		t.Fatalf("expected redefinition error; got %v", err)
+	}
+}

vendor/github.com/alecthomas/template/parse/lex.go

@@ -0,0 +1,556 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package parse
+
+import (
+	"fmt"
+	"strings"
+	"unicode"
+	"unicode/utf8"
+)
+
+// item represents a token or text string returned from the scanner.
+type item struct {
+	typ itemType // The type of this item.
+	pos Pos      // The starting position, in bytes, of this item in the input string.
+	val string   // The value of this item.
+}
+
+func (i item) String() string {
+	switch {
+	case i.typ == itemEOF:
+		return "EOF"
+	case i.typ == itemError:
+		return i.val
+	case i.typ > itemKeyword:
+		return fmt.Sprintf("<%s>", i.val)
+	case len(i.val) > 10:
+		return fmt.Sprintf("%.10q...", i.val)
+	}
+	return fmt.Sprintf("%q", i.val)
+}
+
+// itemType identifies the type of lex items.
+type itemType int
+
+const (
+	itemError        itemType = iota // error occurred; value is text of error
+	itemBool                         // boolean constant
+	itemChar                         // printable ASCII character; grab bag for comma etc.
+	itemCharConstant                 // character constant
+	itemComplex                      // complex constant (1+2i); imaginary is just a number
+	itemColonEquals                  // colon-equals (':=') introducing a declaration
+	itemEOF
+	itemField        // alphanumeric identifier starting with '.'
+	itemIdentifier   // alphanumeric identifier not starting with '.'
+	itemLeftDelim    // left action delimiter
+	itemLeftParen    // '(' inside action
+	itemNumber       // simple number, including imaginary
+	itemPipe         // pipe symbol
+	itemRawString    // raw quoted string (includes quotes)
+	itemRightDelim   // right action delimiter
+	itemElideNewline // elide newline after right delim
+	itemRightParen   // ')' inside action
+	itemSpace        // run of spaces separating arguments
+	itemString       // quoted string (includes quotes)
+	itemText         // plain text
+	itemVariable     // variable starting with '$', such as '$' or  '$1' or '$hello'
+	// Keywords appear after all the rest.
+	itemKeyword  // used only to delimit the keywords
+	itemDot      // the cursor, spelled '.'
+	itemDefine   // define keyword
+	itemElse     // else keyword
+	itemEnd      // end keyword
+	itemIf       // if keyword
+	itemNil      // the untyped nil constant, easiest to treat as a keyword
+	itemRange    // range keyword
+	itemTemplate // template keyword
+	itemWith     // with keyword
+)
+
+var key = map[string]itemType{
+	".":        itemDot,
+	"define":   itemDefine,
+	"else":     itemElse,
+	"end":      itemEnd,
+	"if":       itemIf,
+	"range":    itemRange,
+	"nil":      itemNil,
+	"template": itemTemplate,
+	"with":     itemWith,
+}
+
+const eof = -1
+
+// stateFn represents the state of the scanner as a function that returns the next state.
+type stateFn func(*lexer) stateFn
+
+// lexer holds the state of the scanner.
+type lexer struct {
+	name       string    // the name of the input; used only for error reports
+	input      string    // the string being scanned
+	leftDelim  string    // start of action
+	rightDelim string    // end of action
+	state      stateFn   // the next lexing function to enter
+	pos        Pos       // current position in the input
+	start      Pos       // start position of this item
+	width      Pos       // width of last rune read from input
+	lastPos    Pos       // position of most recent item returned by nextItem
+	items      chan item // channel of scanned items
+	parenDepth int       // nesting depth of ( ) exprs
+}
+
+// next returns the next rune in the input.
+func (l *lexer) next() rune {
+	if int(l.pos) >= len(l.input) {
+		l.width = 0
+		return eof
+	}
+	r, w := utf8.DecodeRuneInString(l.input[l.pos:])
+	l.width = Pos(w)
+	l.pos += l.width
+	return r
+}
+
+// peek returns but does not consume the next rune in the input.
+func (l *lexer) peek() rune {
+	r := l.next()
+	l.backup()
+	return r
+}
+
+// backup steps back one rune. Can only be called once per call of next.
+func (l *lexer) backup() {
+	l.pos -= l.width
+}
+
+// emit passes an item back to the client.
+func (l *lexer) emit(t itemType) {
+	l.items <- item{t, l.start, l.input[l.start:l.pos]}
+	l.start = l.pos
+}
+
+// ignore skips over the pending input before this point.
+func (l *lexer) ignore() {
+	l.start = l.pos
+}
+
+// accept consumes the next rune if it's from the valid set.
+func (l *lexer) accept(valid string) bool {
+	if strings.IndexRune(valid, l.next()) >= 0 {
+		return true
+	}
+	l.backup()
+	return false
+}
+
+// acceptRun consumes a run of runes from the valid set.
+func (l *lexer) acceptRun(valid string) {
+	for strings.IndexRune(valid, l.next()) >= 0 {
+	}
+	l.backup()
+}
+
+// lineNumber reports which line we're on, based on the position of
+// the previous item returned by nextItem. Doing it this way
+// means we don't have to worry about peek double counting.
+func (l *lexer) lineNumber() int {
+	return 1 + strings.Count(l.input[:l.lastPos], "\n")
+}
+
+// errorf returns an error token and terminates the scan by passing
+// back a nil pointer that will be the next state, terminating l.nextItem.
+func (l *lexer) errorf(format string, args ...interface{}) stateFn {
+	l.items <- item{itemError, l.start, fmt.Sprintf(format, args...)}
+	return nil
+}
+
+// nextItem returns the next item from the input.
+func (l *lexer) nextItem() item {
+	item := <-l.items
+	l.lastPos = item.pos
+	return item
+}
+
+// lex creates a new scanner for the input string.
+func lex(name, input, left, right string) *lexer {
+	if left == "" {
+		left = leftDelim
+	}
+	if right == "" {
+		right = rightDelim
+	}
+	l := &lexer{
+		name:       name,
+		input:      input,
+		leftDelim:  left,
+		rightDelim: right,
+		items:      make(chan item),
+	}
+	go l.run()
+	return l
+}
+
+// run runs the state machine for the lexer.
+func (l *lexer) run() {
+	for l.state = lexText; l.state != nil; {
+		l.state = l.state(l)
+	}
+}
+
+// state functions
+
+const (
+	leftDelim    = "{{"
+	rightDelim   = "}}"
+	leftComment  = "/*"
+	rightComment = "*/"
+)
+
+// lexText scans until an opening action delimiter, "{{".
+func lexText(l *lexer) stateFn {
+	for {
+		if strings.HasPrefix(l.input[l.pos:], l.leftDelim) {
+			if l.pos > l.start {
+				l.emit(itemText)
+			}
+			return lexLeftDelim
+		}
+		if l.next() == eof {
+			break
+		}
+	}
+	// Correctly reached EOF.
+	if l.pos > l.start {
+		l.emit(itemText)
+	}
+	l.emit(itemEOF)
+	return nil
+}
+
+// lexLeftDelim scans the left delimiter, which is known to be present.
+func lexLeftDelim(l *lexer) stateFn {
+	l.pos += Pos(len(l.leftDelim))
+	if strings.HasPrefix(l.input[l.pos:], leftComment) {
+		return lexComment
+	}
+	l.emit(itemLeftDelim)
+	l.parenDepth = 0
+	return lexInsideAction
+}
+
+// lexComment scans a comment. The left comment marker is known to be present.
+func lexComment(l *lexer) stateFn {
+	l.pos += Pos(len(leftComment))
+	i := strings.Index(l.input[l.pos:], rightComment)
+	if i < 0 {
+		return l.errorf("unclosed comment")
+	}
+	l.pos += Pos(i + len(rightComment))
+	if !strings.HasPrefix(l.input[l.pos:], l.rightDelim) {
+		return l.errorf("comment ends before closing delimiter")
+
+	}
+	l.pos += Pos(len(l.rightDelim))
+	l.ignore()
+	return lexText
+}
+
+// lexRightDelim scans the right delimiter, which is known to be present.
+func lexRightDelim(l *lexer) stateFn {
+	l.pos += Pos(len(l.rightDelim))
+	l.emit(itemRightDelim)
+	if l.peek() == '\\' {
+		l.pos++
+		l.emit(itemElideNewline)
+	}
+	return lexText
+}
+
+// lexInsideAction scans the elements inside action delimiters.
+func lexInsideAction(l *lexer) stateFn {
+	// Either number, quoted string, or identifier.
+	// Spaces separate arguments; runs of spaces turn into itemSpace.
+	// Pipe symbols separate and are emitted.
+	if strings.HasPrefix(l.input[l.pos:], l.rightDelim+"\\") || strings.HasPrefix(l.input[l.pos:], l.rightDelim) {
+		if l.parenDepth == 0 {
+			return lexRightDelim
+		}
+		return l.errorf("unclosed left paren")
+	}
+	switch r := l.next(); {
+	case r == eof || isEndOfLine(r):
+		return l.errorf("unclosed action")
+	case isSpace(r):
+		return lexSpace
+	case r == ':':
+		if l.next() != '=' {
+			return l.errorf("expected :=")
+		}
+		l.emit(itemColonEquals)
+	case r == '|':
+		l.emit(itemPipe)
+	case r == '"':
+		return lexQuote
+	case r == '`':
+		return lexRawQuote
+	case r == '$':
+		return lexVariable
+	case r == '\'':
+		return lexChar
+	case r == '.':
+		// special look-ahead for ".field" so we don't break l.backup().
+		if l.pos < Pos(len(l.input)) {
+			r := l.input[l.pos]
+			if r < '0' || '9' < r {
+				return lexField
+			}
+		}
+		fallthrough // '.' can start a number.
+	case r == '+' || r == '-' || ('0' <= r && r <= '9'):
+		l.backup()
+		return lexNumber
+	case isAlphaNumeric(r):
+		l.backup()
+		return lexIdentifier
+	case r == '(':
+		l.emit(itemLeftParen)
+		l.parenDepth++
+		return lexInsideAction
+	case r == ')':
+		l.emit(itemRightParen)
+		l.parenDepth--
+		if l.parenDepth < 0 {
+			return l.errorf("unexpected right paren %#U", r)
+		}
+		return lexInsideAction
+	case r <= unicode.MaxASCII && unicode.IsPrint(r):
+		l.emit(itemChar)
+		return lexInsideAction
+	default:
+		return l.errorf("unrecognized character in action: %#U", r)
+	}
+	return lexInsideAction
+}
+
+// lexSpace scans a run of space characters.
+// One space has already been seen.
+func lexSpace(l *lexer) stateFn {
+	for isSpace(l.peek()) {
+		l.next()
+	}
+	l.emit(itemSpace)
+	return lexInsideAction
+}
+
+// lexIdentifier scans an alphanumeric.
+func lexIdentifier(l *lexer) stateFn {
+Loop:
+	for {
+		switch r := l.next(); {
+		case isAlphaNumeric(r):
+			// absorb.
+		default:
+			l.backup()
+			word := l.input[l.start:l.pos]
+			if !l.atTerminator() {
+				return l.errorf("bad character %#U", r)
+			}
+			switch {
+			case key[word] > itemKeyword:
+				l.emit(key[word])
+			case word[0] == '.':
+				l.emit(itemField)
+			case word == "true", word == "false":
+				l.emit(itemBool)
+			default:
+				l.emit(itemIdentifier)
+			}
+			break Loop
+		}
+	}
+	return lexInsideAction
+}
+
+// lexField scans a field: .Alphanumeric.
+// The . has been scanned.
+func lexField(l *lexer) stateFn {
+	return lexFieldOrVariable(l, itemField)
+}
+
+// lexVariable scans a Variable: $Alphanumeric.
+// The $ has been scanned.
+func lexVariable(l *lexer) stateFn {
+	if l.atTerminator() { // Nothing interesting follows -> "$".
+		l.emit(itemVariable)
+		return lexInsideAction
+	}
+	return lexFieldOrVariable(l, itemVariable)
+}
+
+// lexVariable scans a field or variable: [.$]Alphanumeric.
+// The . or $ has been scanned.
+func lexFieldOrVariable(l *lexer, typ itemType) stateFn {
+	if l.atTerminator() { // Nothing interesting follows -> "." or "$".
+		if typ == itemVariable {
+			l.emit(itemVariable)
+		} else {
+			l.emit(itemDot)
+		}
+		return lexInsideAction
+	}
+	var r rune
+	for {
+		r = l.next()
+		if !isAlphaNumeric(r) {
+			l.backup()
+			break
+		}
+	}
+	if !l.atTerminator() {
+		return l.errorf("bad character %#U", r)
+	}
+	l.emit(typ)
+	return lexInsideAction
+}
+
+// atTerminator reports whether the input is at valid termination character to
+// appear after an identifier. Breaks .X.Y into two pieces. Also catches cases
+// like "$x+2" not being acceptable without a space, in case we decide one
+// day to implement arithmetic.
+func (l *lexer) atTerminator() bool {
+	r := l.peek()
+	if isSpace(r) || isEndOfLine(r) {
+		return true
+	}
+	switch r {
+	case eof, '.', ',', '|', ':', ')', '(':
+		return true
+	}
+	// Does r start the delimiter? This can be ambiguous (with delim=="//", $x/2 will
+	// succeed but should fail) but only in extremely rare cases caused by willfully
+	// bad choice of delimiter.
+	if rd, _ := utf8.DecodeRuneInString(l.rightDelim); rd == r {
+		return true
+	}
+	return false
+}
+
+// lexChar scans a character constant. The initial quote is already
+// scanned. Syntax checking is done by the parser.
+func lexChar(l *lexer) stateFn {
+Loop:
+	for {
+		switch l.next() {
+		case '\\':
+			if r := l.next(); r != eof && r != '\n' {
+				break
+			}
+			fallthrough
+		case eof, '\n':
+			return l.errorf("unterminated character constant")
+		case '\'':
+			break Loop
+		}
+	}
+	l.emit(itemCharConstant)
+	return lexInsideAction
+}
+
+// lexNumber scans a number: decimal, octal, hex, float, or imaginary. This
+// isn't a perfect number scanner - for instance it accepts "." and "0x0.2"
+// and "089" - but when it's wrong the input is invalid and the parser (via
+// strconv) will notice.
+func lexNumber(l *lexer) stateFn {
+	if !l.scanNumber() {
+		return l.errorf("bad number syntax: %q", l.input[l.start:l.pos])
+	}
+	if sign := l.peek(); sign == '+' || sign == '-' {
+		// Complex: 1+2i. No spaces, must end in 'i'.
+		if !l.scanNumber() || l.input[l.pos-1] != 'i' {
+			return l.errorf("bad number syntax: %q", l.input[l.start:l.pos])
+		}
+		l.emit(itemComplex)
+	} else {
+		l.emit(itemNumber)
+	}
+	return lexInsideAction
+}
+
+func (l *lexer) scanNumber() bool {
+	// Optional leading sign.
+	l.accept("+-")
+	// Is it hex?
+	digits := "0123456789"
+	if l.accept("0") && l.accept("xX") {
+		digits = "0123456789abcdefABCDEF"
+	}
+	l.acceptRun(digits)
+	if l.accept(".") {
+		l.acceptRun(digits)
+	}
+	if l.accept("eE") {
+		l.accept("+-")
+		l.acceptRun("0123456789")
+	}
+	// Is it imaginary?
+	l.accept("i")
+	// Next thing mustn't be alphanumeric.
+	if isAlphaNumeric(l.peek()) {
+		l.next()
+		return false
+	}
+	return true
+}
+
+// lexQuote scans a quoted string.
+func lexQuote(l *lexer) stateFn {
+Loop:
+	for {
+		switch l.next() {
+		case '\\':
+			if r := l.next(); r != eof && r != '\n' {
+				break
+			}
+			fallthrough
+		case eof, '\n':
+			return l.errorf("unterminated quoted string")
+		case '"':
+			break Loop
+		}
+	}
+	l.emit(itemString)
+	return lexInsideAction
+}
+
+// lexRawQuote scans a raw quoted string.
+func lexRawQuote(l *lexer) stateFn {
+Loop:
+	for {
+		switch l.next() {
+		case eof, '\n':
+			return l.errorf("unterminated raw quoted string")
+		case '`':
+			break Loop
+		}
+	}
+	l.emit(itemRawString)
+	return lexInsideAction
+}
+
+// isSpace reports whether r is a space character.
+func isSpace(r rune) bool {
+	return r == ' ' || r == '\t'
+}
+
+// isEndOfLine reports whether r is an end-of-line character.
+func isEndOfLine(r rune) bool {
+	return r == '\r' || r == '\n'
+}
+
+// isAlphaNumeric reports whether r is an alphabetic, digit, or underscore.
+func isAlphaNumeric(r rune) bool {
+	return r == '_' || unicode.IsLetter(r) || unicode.IsDigit(r)
+}

vendor/github.com/alecthomas/template/parse/lex_test.go

@@ -0,0 +1,468 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package parse
+
+import (
+	"fmt"
+	"testing"
+)
+
+// Make the types prettyprint.
+var itemName = map[itemType]string{
+	itemError:        "error",
+	itemBool:         "bool",
+	itemChar:         "char",
+	itemCharConstant: "charconst",
+	itemComplex:      "complex",
+	itemColonEquals:  ":=",
+	itemEOF:          "EOF",
+	itemField:        "field",
+	itemIdentifier:   "identifier",
+	itemLeftDelim:    "left delim",
+	itemLeftParen:    "(",
+	itemNumber:       "number",
+	itemPipe:         "pipe",
+	itemRawString:    "raw string",
+	itemRightDelim:   "right delim",
+	itemElideNewline: "elide newline",
+	itemRightParen:   ")",
+	itemSpace:        "space",
+	itemString:       "string",
+	itemVariable:     "variable",
+
+	// keywords
+	itemDot:      ".",
+	itemDefine:   "define",
+	itemElse:     "else",
+	itemIf:       "if",
+	itemEnd:      "end",
+	itemNil:      "nil",
+	itemRange:    "range",
+	itemTemplate: "template",
+	itemWith:     "with",
+}
+
+func (i itemType) String() string {
+	s := itemName[i]
+	if s == "" {
+		return fmt.Sprintf("item%d", int(i))
+	}
+	return s
+}
+
+type lexTest struct {
+	name  string
+	input string
+	items []item
+}
+
+var (
+	tEOF          = item{itemEOF, 0, ""}
+	tFor          = item{itemIdentifier, 0, "for"}
+	tLeft         = item{itemLeftDelim, 0, "{{"}
+	tLpar         = item{itemLeftParen, 0, "("}
+	tPipe         = item{itemPipe, 0, "|"}
+	tQuote        = item{itemString, 0, `"abc \n\t\" "`}
+	tRange        = item{itemRange, 0, "range"}
+	tRight        = item{itemRightDelim, 0, "}}"}
+	tElideNewline = item{itemElideNewline, 0, "\\"}
+	tRpar         = item{itemRightParen, 0, ")"}
+	tSpace        = item{itemSpace, 0, " "}
+	raw           = "`" + `abc\n\t\" ` + "`"
+	tRawQuote     = item{itemRawString, 0, raw}
+)
+
+var lexTests = []lexTest{
+	{"empty", "", []item{tEOF}},
+	{"spaces", " \t\n", []item{{itemText, 0, " \t\n"}, tEOF}},
+	{"text", `now is the time`, []item{{itemText, 0, "now is the time"}, tEOF}},
+	{"elide newline", "{{}}\\", []item{tLeft, tRight, tElideNewline, tEOF}},
+	{"text with comment", "hello-{{/* this is a comment */}}-world", []item{
+		{itemText, 0, "hello-"},
+		{itemText, 0, "-world"},
+		tEOF,
+	}},
+	{"punctuation", "{{,@% }}", []item{
+		tLeft,
+		{itemChar, 0, ","},
+		{itemChar, 0, "@"},
+		{itemChar, 0, "%"},
+		tSpace,
+		tRight,
+		tEOF,
+	}},
+	{"parens", "{{((3))}}", []item{
+		tLeft,
+		tLpar,
+		tLpar,
+		{itemNumber, 0, "3"},
+		tRpar,
+		tRpar,
+		tRight,
+		tEOF,
+	}},
+	{"empty action", `{{}}`, []item{tLeft, tRight, tEOF}},
+	{"for", `{{for}}`, []item{tLeft, tFor, tRight, tEOF}},
+	{"quote", `{{"abc \n\t\" "}}`, []item{tLeft, tQuote, tRight, tEOF}},
+	{"raw quote", "{{" + raw + "}}", []item{tLeft, tRawQuote, tRight, tEOF}},
+	{"numbers", "{{1 02 0x14 -7.2i 1e3 +1.2e-4 4.2i 1+2i}}", []item{
+		tLeft,
+		{itemNumber, 0, "1"},
+		tSpace,
+		{itemNumber, 0, "02"},
+		tSpace,
+		{itemNumber, 0, "0x14"},
+		tSpace,
+		{itemNumber, 0, "-7.2i"},
+		tSpace,
+		{itemNumber, 0, "1e3"},
+		tSpace,
+		{itemNumber, 0, "+1.2e-4"},
+		tSpace,
+		{itemNumber, 0, "4.2i"},
+		tSpace,
+		{itemComplex, 0, "1+2i"},
+		tRight,
+		tEOF,
+	}},
+	{"characters", `{{'a' '\n' '\'' '\\' '\u00FF' '\xFF' '本'}}`, []item{
+		tLeft,
+		{itemCharConstant, 0, `'a'`},
+		tSpace,
+		{itemCharConstant, 0, `'\n'`},
+		tSpace,
+		{itemCharConstant, 0, `'\''`},
+		tSpace,
+		{itemCharConstant, 0, `'\\'`},
+		tSpace,
+		{itemCharConstant, 0, `'\u00FF'`},
+		tSpace,
+		{itemCharConstant, 0, `'\xFF'`},
+		tSpace,
+		{itemCharConstant, 0, `'本'`},
+		tRight,
+		tEOF,
+	}},
+	{"bools", "{{true false}}", []item{
+		tLeft,
+		{itemBool, 0, "true"},
+		tSpace,
+		{itemBool, 0, "false"},
+		tRight,
+		tEOF,
+	}},
+	{"dot", "{{.}}", []item{
+		tLeft,
+		{itemDot, 0, "."},
+		tRight,
+		tEOF,
+	}},
+	{"nil", "{{nil}}", []item{
+		tLeft,
+		{itemNil, 0, "nil"},
+		tRight,
+		tEOF,
+	}},
+	{"dots", "{{.x . .2 .x.y.z}}", []item{
+		tLeft,
+		{itemField, 0, ".x"},
+		tSpace,
+		{itemDot, 0, "."},
+		tSpace,
+		{itemNumber, 0, ".2"},
+		tSpace,
+		{itemField, 0, ".x"},
+		{itemField, 0, ".y"},
+		{itemField, 0, ".z"},
+		tRight,
+		tEOF,
+	}},
+	{"keywords", "{{range if else end with}}", []item{
+		tLeft,
+		{itemRange, 0, "range"},
+		tSpace,
+		{itemIf, 0, "if"},
+		tSpace,
+		{itemElse, 0, "else"},
+		tSpace,
+		{itemEnd, 0, "end"},
+		tSpace,
+		{itemWith, 0, "with"},
+		tRight,
+		tEOF,
+	}},
+	{"variables", "{{$c := printf $ $hello $23 $ $var.Field .Method}}", []item{
+		tLeft,
+		{itemVariable, 0, "$c"},
+		tSpace,
+		{itemColonEquals, 0, ":="},
+		tSpace,
+		{itemIdentifier, 0, "printf"},
+		tSpace,
+		{itemVariable, 0, "$"},
+		tSpace,
+		{itemVariable, 0, "$hello"},
+		tSpace,
+		{itemVariable, 0, "$23"},
+		tSpace,
+		{itemVariable, 0, "$"},
+		tSpace,
+		{itemVariable, 0, "$var"},
+		{itemField, 0, ".Field"},
+		tSpace,
+		{itemField, 0, ".Method"},
+		tRight,
+		tEOF,
+	}},
+	{"variable invocation", "{{$x 23}}", []item{
+		tLeft,
+		{itemVariable, 0, "$x"},
+		tSpace,
+		{itemNumber, 0, "23"},
+		tRight,
+		tEOF,
+	}},
+	{"pipeline", `intro {{echo hi 1.2 |noargs|args 1 "hi"}} outro`, []item{
+		{itemText, 0, "intro "},
+		tLeft,
+		{itemIdentifier, 0, "echo"},
+		tSpace,
+		{itemIdentifier, 0, "hi"},
+		tSpace,
+		{itemNumber, 0, "1.2"},
+		tSpace,
+		tPipe,
+		{itemIdentifier, 0, "noargs"},
+		tPipe,
+		{itemIdentifier, 0, "args"},
+		tSpace,
+		{itemNumber, 0, "1"},
+		tSpace,
+		{itemString, 0, `"hi"`},
+		tRight,
+		{itemText, 0, " outro"},
+		tEOF,
+	}},
+	{"declaration", "{{$v := 3}}", []item{
+		tLeft,
+		{itemVariable, 0, "$v"},
+		tSpace,
+		{itemColonEquals, 0, ":="},
+		tSpace,
+		{itemNumber, 0, "3"},
+		tRight,
+		tEOF,
+	}},
+	{"2 declarations", "{{$v , $w := 3}}", []item{
+		tLeft,
+		{itemVariable, 0, "$v"},
+		tSpace,
+		{itemChar, 0, ","},
+		tSpace,
+		{itemVariable, 0, "$w"},
+		tSpace,
+		{itemColonEquals, 0, ":="},
+		tSpace,
+		{itemNumber, 0, "3"},
+		tRight,
+		tEOF,
+	}},
+	{"field of parenthesized expression", "{{(.X).Y}}", []item{
+		tLeft,
+		tLpar,
+		{itemField, 0, ".X"},
+		tRpar,
+		{itemField, 0, ".Y"},
+		tRight,
+		tEOF,
+	}},
+	// errors
+	{"badchar", "#{{\x01}}", []item{
+		{itemText, 0, "#"},
+		tLeft,
+		{itemError, 0, "unrecognized character in action: U+0001"},
+	}},
+	{"unclosed action", "{{\n}}", []item{
+		tLeft,
+		{itemError, 0, "unclosed action"},
+	}},
+	{"EOF in action", "{{range", []item{
+		tLeft,
+		tRange,
+		{itemError, 0, "unclosed action"},
+	}},
+	{"unclosed quote", "{{\"\n\"}}", []item{
+		tLeft,
+		{itemError, 0, "unterminated quoted string"},
+	}},
+	{"unclosed raw quote", "{{`xx\n`}}", []item{
+		tLeft,
+		{itemError, 0, "unterminated raw quoted string"},
+	}},
+	{"unclosed char constant", "{{'\n}}", []item{
+		tLeft,
+		{itemError, 0, "unterminated character constant"},
+	}},
+	{"bad number", "{{3k}}", []item{
+		tLeft,
+		{itemError, 0, `bad number syntax: "3k"`},
+	}},
+	{"unclosed paren", "{{(3}}", []item{
+		tLeft,
+		tLpar,
+		{itemNumber, 0, "3"},
+		{itemError, 0, `unclosed left paren`},
+	}},
+	{"extra right paren", "{{3)}}", []item{
+		tLeft,
+		{itemNumber, 0, "3"},
+		tRpar,
+		{itemError, 0, `unexpected right paren U+0029 ')'`},
+	}},
+
+	// Fixed bugs
+	// Many elements in an action blew the lookahead until
+	// we made lexInsideAction not loop.
+	{"long pipeline deadlock", "{{|||||}}", []item{
+		tLeft,
+		tPipe,
+		tPipe,
+		tPipe,
+		tPipe,
+		tPipe,
+		tRight,
+		tEOF,
+	}},
+	{"text with bad comment", "hello-{{/*/}}-world", []item{
+		{itemText, 0, "hello-"},
+		{itemError, 0, `unclosed comment`},
+	}},
+	{"text with comment close separted from delim", "hello-{{/* */ }}-world", []item{
+		{itemText, 0, "hello-"},
+		{itemError, 0, `comment ends before closing delimiter`},
+	}},
+	// This one is an error that we can't catch because it breaks templates with
+	// minimized JavaScript. Should have fixed it before Go 1.1.
+	{"unmatched right delimiter", "hello-{.}}-world", []item{
+		{itemText, 0, "hello-{.}}-world"},
+		tEOF,
+	}},
+}
+
+// collect gathers the emitted items into a slice.
+func collect(t *lexTest, left, right string) (items []item) {
+	l := lex(t.name, t.input, left, right)
+	for {
+		item := l.nextItem()
+		items = append(items, item)
+		if item.typ == itemEOF || item.typ == itemError {
+			break
+		}
+	}
+	return
+}
+
+func equal(i1, i2 []item, checkPos bool) bool {
+	if len(i1) != len(i2) {
+		return false
+	}
+	for k := range i1 {
+		if i1[k].typ != i2[k].typ {
+			return false
+		}
+		if i1[k].val != i2[k].val {
+			return false
+		}
+		if checkPos && i1[k].pos != i2[k].pos {
+			return false
+		}
+	}
+	return true
+}
+
+func TestLex(t *testing.T) {
+	for _, test := range lexTests {
+		items := collect(&test, "", "")
+		if !equal(items, test.items, false) {
+			t.Errorf("%s: got\n\t%+v\nexpected\n\t%v", test.name, items, test.items)
+		}
+	}
+}
+
+// Some easy cases from above, but with delimiters $$ and @@
+var lexDelimTests = []lexTest{
+	{"punctuation", "$$,@%{{}}@@", []item{
+		tLeftDelim,
+		{itemChar, 0, ","},
+		{itemChar, 0, "@"},
+		{itemChar, 0, "%"},
+		{itemChar, 0, "{"},
+		{itemChar, 0, "{"},
+		{itemChar, 0, "}"},
+		{itemChar, 0, "}"},
+		tRightDelim,
+		tEOF,
+	}},
+	{"empty action", `$$@@`, []item{tLeftDelim, tRightDelim, tEOF}},
+	{"for", `$$for@@`, []item{tLeftDelim, tFor, tRightDelim, tEOF}},
+	{"quote", `$$"abc \n\t\" "@@`, []item{tLeftDelim, tQuote, tRightDelim, tEOF}},
+	{"raw quote", "$$" + raw + "@@", []item{tLeftDelim, tRawQuote, tRightDelim, tEOF}},
+}
+
+var (
+	tLeftDelim  = item{itemLeftDelim, 0, "$$"}
+	tRightDelim = item{itemRightDelim, 0, "@@"}
+)
+
+func TestDelims(t *testing.T) {
+	for _, test := range lexDelimTests {
+		items := collect(&test, "$$", "@@")
+		if !equal(items, test.items, false) {
+			t.Errorf("%s: got\n\t%v\nexpected\n\t%v", test.name, items, test.items)
+		}
+	}
+}
+
+var lexPosTests = []lexTest{
+	{"empty", "", []item{tEOF}},
+	{"punctuation", "{{,@%#}}", []item{
+		{itemLeftDelim, 0, "{{"},
+		{itemChar, 2, ","},
+		{itemChar, 3, "@"},
+		{itemChar, 4, "%"},
+		{itemChar, 5, "#"},
+		{itemRightDelim, 6, "}}"},
+		{itemEOF, 8, ""},
+	}},
+	{"sample", "0123{{hello}}xyz", []item{
+		{itemText, 0, "0123"},
+		{itemLeftDelim, 4, "{{"},
+		{itemIdentifier, 6, "hello"},
+		{itemRightDelim, 11, "}}"},
+		{itemText, 13, "xyz"},
+		{itemEOF, 16, ""},
+	}},
+}
+
+// The other tests don't check position, to make the test cases easier to construct.
+// This one does.
+func TestPos(t *testing.T) {
+	for _, test := range lexPosTests {
+		items := collect(&test, "", "")
+		if !equal(items, test.items, true) {
+			t.Errorf("%s: got\n\t%v\nexpected\n\t%v", test.name, items, test.items)
+			if len(items) == len(test.items) {
+				// Detailed print; avoid item.String() to expose the position value.
+				for i := range items {
+					if !equal(items[i:i+1], test.items[i:i+1], true) {
+						i1 := items[i]
+						i2 := test.items[i]
+						t.Errorf("\t#%d: got {%v %d %q} expected  {%v %d %q}", i, i1.typ, i1.pos, i1.val, i2.typ, i2.pos, i2.val)
+					}
+				}
+			}
+		}
+	}
+}

vendor/github.com/alecthomas/template/parse/node.go

@@ -0,0 +1,834 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Parse nodes.
+
+package parse
+
+import (
+	"bytes"
+	"fmt"
+	"strconv"
+	"strings"
+)
+
+var textFormat = "%s" // Changed to "%q" in tests for better error messages.
+
+// A Node is an element in the parse tree. The interface is trivial.
+// The interface contains an unexported method so that only
+// types local to this package can satisfy it.
+type Node interface {
+	Type() NodeType
+	String() string
+	// Copy does a deep copy of the Node and all its components.
+	// To avoid type assertions, some XxxNodes also have specialized
+	// CopyXxx methods that return *XxxNode.
+	Copy() Node
+	Position() Pos // byte position of start of node in full original input string
+	// tree returns the containing *Tree.
+	// It is unexported so all implementations of Node are in this package.
+	tree() *Tree
+}
+
+// NodeType identifies the type of a parse tree node.
+type NodeType int
+
+// Pos represents a byte position in the original input text from which
+// this template was parsed.
+type Pos int
+
+func (p Pos) Position() Pos {
+	return p
+}
+
+// Type returns itself and provides an easy default implementation
+// for embedding in a Node. Embedded in all non-trivial Nodes.
+func (t NodeType) Type() NodeType {
+	return t
+}
+
+const (
+	NodeText       NodeType = iota // Plain text.
+	NodeAction                     // A non-control action such as a field evaluation.
+	NodeBool                       // A boolean constant.
+	NodeChain                      // A sequence of field accesses.
+	NodeCommand                    // An element of a pipeline.
+	NodeDot                        // The cursor, dot.
+	nodeElse                       // An else action. Not added to tree.
+	nodeEnd                        // An end action. Not added to tree.
+	NodeField                      // A field or method name.
+	NodeIdentifier                 // An identifier; always a function name.
+	NodeIf                         // An if action.
+	NodeList                       // A list of Nodes.
+	NodeNil                        // An untyped nil constant.
+	NodeNumber                     // A numerical constant.
+	NodePipe                       // A pipeline of commands.
+	NodeRange                      // A range action.
+	NodeString                     // A string constant.
+	NodeTemplate                   // A template invocation action.
+	NodeVariable                   // A $ variable.
+	NodeWith                       // A with action.
+)
+
+// Nodes.
+
+// ListNode holds a sequence of nodes.
+type ListNode struct {
+	NodeType
+	Pos
+	tr    *Tree
+	Nodes []Node // The element nodes in lexical order.
+}
+
+func (t *Tree) newList(pos Pos) *ListNode {
+	return &ListNode{tr: t, NodeType: NodeList, Pos: pos}
+}
+
+func (l *ListNode) append(n Node) {
+	l.Nodes = append(l.Nodes, n)
+}
+
+func (l *ListNode) tree() *Tree {
+	return l.tr
+}
+
+func (l *ListNode) String() string {
+	b := new(bytes.Buffer)
+	for _, n := range l.Nodes {
+		fmt.Fprint(b, n)
+	}
+	return b.String()
+}
+
+func (l *ListNode) CopyList() *ListNode {
+	if l == nil {
+		return l
+	}
+	n := l.tr.newList(l.Pos)
+	for _, elem := range l.Nodes {
+		n.append(elem.Copy())
+	}
+	return n
+}
+
+func (l *ListNode) Copy() Node {
+	return l.CopyList()
+}
+
+// TextNode holds plain text.
+type TextNode struct {
+	NodeType
+	Pos
+	tr   *Tree
+	Text []byte // The text; may span newlines.
+}
+
+func (t *Tree) newText(pos Pos, text string) *TextNode {
+	return &TextNode{tr: t, NodeType: NodeText, Pos: pos, Text: []byte(text)}
+}
+
+func (t *TextNode) String() string {
+	return fmt.Sprintf(textFormat, t.Text)
+}
+
+func (t *TextNode) tree() *Tree {
+	return t.tr
+}
+
+func (t *TextNode) Copy() Node {
+	return &TextNode{tr: t.tr, NodeType: NodeText, Pos: t.Pos, Text: append([]byte{}, t.Text...)}
+}
+
+// PipeNode holds a pipeline with optional declaration
+type PipeNode struct {
+	NodeType
+	Pos
+	tr   *Tree
+	Line int             // The line number in the input (deprecated; kept for compatibility)
+	Decl []*VariableNode // Variable declarations in lexical order.
+	Cmds []*CommandNode  // The commands in lexical order.
+}
+
+func (t *Tree) newPipeline(pos Pos, line int, decl []*VariableNode) *PipeNode {
+	return &PipeNode{tr: t, NodeType: NodePipe, Pos: pos, Line: line, Decl: decl}
+}
+
+func (p *PipeNode) append(command *CommandNode) {
+	p.Cmds = append(p.Cmds, command)
+}
+
+func (p *PipeNode) String() string {
+	s := ""
+	if len(p.Decl) > 0 {
+		for i, v := range p.Decl {
+			if i > 0 {
+				s += ", "
+			}
+			s += v.String()
+		}
+		s += " := "
+	}
+	for i, c := range p.Cmds {
+		if i > 0 {
+			s += " | "
+		}
+		s += c.String()
+	}
+	return s
+}
+
+func (p *PipeNode) tree() *Tree {
+	return p.tr
+}
+
+func (p *PipeNode) CopyPipe() *PipeNode {
+	if p == nil {
+		return p
+	}
+	var decl []*VariableNode
+	for _, d := range p.Decl {
+		decl = append(decl, d.Copy().(*VariableNode))
+	}
+	n := p.tr.newPipeline(p.Pos, p.Line, decl)
+	for _, c := range p.Cmds {
+		n.append(c.Copy().(*CommandNode))
+	}
+	return n
+}
+
+func (p *PipeNode) Copy() Node {
+	return p.CopyPipe()
+}
+
+// ActionNode holds an action (something bounded by delimiters).
+// Control actions have their own nodes; ActionNode represents simple
+// ones such as field evaluations and parenthesized pipelines.
+type ActionNode struct {
+	NodeType
+	Pos
+	tr   *Tree
+	Line int       // The line number in the input (deprecated; kept for compatibility)
+	Pipe *PipeNode // The pipeline in the action.
+}
+
+func (t *Tree) newAction(pos Pos, line int, pipe *PipeNode) *ActionNode {
+	return &ActionNode{tr: t, NodeType: NodeAction, Pos: pos, Line: line, Pipe: pipe}
+}
+
+func (a *ActionNode) String() string {
+	return fmt.Sprintf("{{%s}}", a.Pipe)
+
+}
+
+func (a *ActionNode) tree() *Tree {
+	return a.tr
+}
+
+func (a *ActionNode) Copy() Node {
+	return a.tr.newAction(a.Pos, a.Line, a.Pipe.CopyPipe())
+
+}
+
+// CommandNode holds a command (a pipeline inside an evaluating action).
+type CommandNode struct {
+	NodeType
+	Pos
+	tr   *Tree
+	Args []Node // Arguments in lexical order: Identifier, field, or constant.
+}
+
+func (t *Tree) newCommand(pos Pos) *CommandNode {
+	return &CommandNode{tr: t, NodeType: NodeCommand, Pos: pos}
+}
+
+func (c *CommandNode) append(arg Node) {
+	c.Args = append(c.Args, arg)
+}
+
+func (c *CommandNode) String() string {
+	s := ""
+	for i, arg := range c.Args {
+		if i > 0 {
+			s += " "
+		}
+		if arg, ok := arg.(*PipeNode); ok {
+			s += "(" + arg.String() + ")"
+			continue
+		}
+		s += arg.String()
+	}
+	return s
+}
+
+func (c *CommandNode) tree() *Tree {
+	return c.tr
+}
+
+func (c *CommandNode) Copy() Node {
+	if c == nil {
+		return c
+	}
+	n := c.tr.newCommand(c.Pos)
+	for _, c := range c.Args {
+		n.append(c.Copy())
+	}
+	return n
+}
+
+// IdentifierNode holds an identifier.
+type IdentifierNode struct {
+	NodeType
+	Pos
+	tr    *Tree
+	Ident string // The identifier's name.
+}
+
+// NewIdentifier returns a new IdentifierNode with the given identifier name.
+func NewIdentifier(ident string) *IdentifierNode {
+	return &IdentifierNode{NodeType: NodeIdentifier, Ident: ident}
+}
+
+// SetPos sets the position. NewIdentifier is a public method so we can't modify its signature.
+// Chained for convenience.
+// TODO: fix one day?
+func (i *IdentifierNode) SetPos(pos Pos) *IdentifierNode {
+	i.Pos = pos
+	return i
+}
+
+// SetTree sets the parent tree for the node. NewIdentifier is a public method so we can't modify its signature.
+// Chained for convenience.
+// TODO: fix one day?
+func (i *IdentifierNode) SetTree(t *Tree) *IdentifierNode {
+	i.tr = t
+	return i
+}
+
+func (i *IdentifierNode) String() string {
+	return i.Ident
+}
+
+func (i *IdentifierNode) tree() *Tree {
+	return i.tr
+}
+
+func (i *IdentifierNode) Copy() Node {
+	return NewIdentifier(i.Ident).SetTree(i.tr).SetPos(i.Pos)
+}
+
+// VariableNode holds a list of variable names, possibly with chained field
+// accesses. The dollar sign is part of the (first) name.
+type VariableNode struct {
+	NodeType
+	Pos
+	tr    *Tree
+	Ident []string // Variable name and fields in lexical order.
+}
+
+func (t *Tree) newVariable(pos Pos, ident string) *VariableNode {
+	return &VariableNode{tr: t, NodeType: NodeVariable, Pos: pos, Ident: strings.Split(ident, ".")}
+}
+
+func (v *VariableNode) String() string {
+	s := ""
+	for i, id := range v.Ident {
+		if i > 0 {
+			s += "."
+		}
+		s += id
+	}
+	return s
+}
+
+func (v *VariableNode) tree() *Tree {
+	return v.tr
+}
+
+func (v *VariableNode) Copy() Node {
+	return &VariableNode{tr: v.tr, NodeType: NodeVariable, Pos: v.Pos, Ident: append([]string{}, v.Ident...)}
+}
+
+// DotNode holds the special identifier '.'.
+type DotNode struct {
+	NodeType
+	Pos
+	tr *Tree
+}
+
+func (t *Tree) newDot(pos Pos) *DotNode {
+	return &DotNode{tr: t, NodeType: NodeDot, Pos: pos}
+}
+
+func (d *DotNode) Type() NodeType {
+	// Override method on embedded NodeType for API compatibility.
+	// TODO: Not really a problem; could change API without effect but
+	// api tool complains.
+	return NodeDot
+}
+
+func (d *DotNode) String() string {
+	return "."
+}
+
+func (d *DotNode) tree() *Tree {
+	return d.tr
+}
+
+func (d *DotNode) Copy() Node {
+	return d.tr.newDot(d.Pos)
+}
+
+// NilNode holds the special identifier 'nil' representing an untyped nil constant.
+type NilNode struct {
+	NodeType
+	Pos
+	tr *Tree
+}
+
+func (t *Tree) newNil(pos Pos) *NilNode {
+	return &NilNode{tr: t, NodeType: NodeNil, Pos: pos}
+}
+
+func (n *NilNode) Type() NodeType {
+	// Override method on embedded NodeType for API compatibility.
+	// TODO: Not really a problem; could change API without effect but
+	// api tool complains.
+	return NodeNil
+}
+
+func (n *NilNode) String() string {
+	return "nil"
+}
+
+func (n *NilNode) tree() *Tree {
+	return n.tr
+}
+
+func (n *NilNode) Copy() Node {
+	return n.tr.newNil(n.Pos)
+}
+
+// FieldNode holds a field (identifier starting with '.').
+// The names may be chained ('.x.y').
+// The period is dropped from each ident.
+type FieldNode struct {
+	NodeType
+	Pos
+	tr    *Tree
+	Ident []string // The identifiers in lexical order.
+}
+
+func (t *Tree) newField(pos Pos, ident string) *FieldNode {
+	return &FieldNode{tr: t, NodeType: NodeField, Pos: pos, Ident: strings.Split(ident[1:], ".")} // [1:] to drop leading period
+}
+
+func (f *FieldNode) String() string {
+	s := ""
+	for _, id := range f.Ident {
+		s += "." + id
+	}
+	return s
+}
+
+func (f *FieldNode) tree() *Tree {
+	return f.tr
+}
+
+func (f *FieldNode) Copy() Node {
+	return &FieldNode{tr: f.tr, NodeType: NodeField, Pos: f.Pos, Ident: append([]string{}, f.Ident...)}
+}
+
+// ChainNode holds a term followed by a chain of field accesses (identifier starting with '.').
+// The names may be chained ('.x.y').
+// The periods are dropped from each ident.
+type ChainNode struct {
+	NodeType
+	Pos
+	tr    *Tree
+	Node  Node
+	Field []string // The identifiers in lexical order.
+}
+
+func (t *Tree) newChain(pos Pos, node Node) *ChainNode {
+	return &ChainNode{tr: t, NodeType: NodeChain, Pos: pos, Node: node}
+}
+
+// Add adds the named field (which should start with a period) to the end of the chain.
+func (c *ChainNode) Add(field string) {
+	if len(field) == 0 || field[0] != '.' {
+		panic("no dot in field")
+	}
+	field = field[1:] // Remove leading dot.
+	if field == "" {
+		panic("empty field")
+	}
+	c.Field = append(c.Field, field)
+}
+
+func (c *ChainNode) String() string {
+	s := c.Node.String()
+	if _, ok := c.Node.(*PipeNode); ok {
+		s = "(" + s + ")"
+	}
+	for _, field := range c.Field {
+		s += "." + field
+	}
+	return s
+}
+
+func (c *ChainNode) tree() *Tree {
+	return c.tr
+}
+
+func (c *ChainNode) Copy() Node {
+	return &ChainNode{tr: c.tr, NodeType: NodeChain, Pos: c.Pos, Node: c.Node, Field: append([]string{}, c.Field...)}
+}
+
+// BoolNode holds a boolean constant.
+type BoolNode struct {
+	NodeType
+	Pos
+	tr   *Tree
+	True bool // The value of the boolean constant.
+}
+
+func (t *Tree) newBool(pos Pos, true bool) *BoolNode {
+	return &BoolNode{tr: t, NodeType: NodeBool, Pos: pos, True: true}
+}
+
+func (b *BoolNode) String() string {
+	if b.True {
+		return "true"
+	}
+	return "false"
+}
+
+func (b *BoolNode) tree() *Tree {
+	return b.tr
+}
+
+func (b *BoolNode) Copy() Node {
+	return b.tr.newBool(b.Pos, b.True)
+}
+
+// NumberNode holds a number: signed or unsigned integer, float, or complex.
+// The value is parsed and stored under all the types that can represent the value.
+// This simulates in a small amount of code the behavior of Go's ideal constants.
+type NumberNode struct {
+	NodeType
+	Pos
+	tr         *Tree
+	IsInt      bool       // Number has an integral value.
+	IsUint     bool       // Number has an unsigned integral value.
+	IsFloat    bool       // Number has a floating-point value.
+	IsComplex  bool       // Number is complex.
+	Int64      int64      // The signed integer value.
+	Uint64     uint64     // The unsigned integer value.
+	Float64    float64    // The floating-point value.
+	Complex128 complex128 // The complex value.
+	Text       string     // The original textual representation from the input.
+}
+
+func (t *Tree) newNumber(pos Pos, text string, typ itemType) (*NumberNode, error) {
+	n := &NumberNode{tr: t, NodeType: NodeNumber, Pos: pos, Text: text}
+	switch typ {
+	case itemCharConstant:
+		rune, _, tail, err := strconv.UnquoteChar(text[1:], text[0])
+		if err != nil {
+			return nil, err
+		}
+		if tail != "'" {
+			return nil, fmt.Errorf("malformed character constant: %s", text)
+		}
+		n.Int64 = int64(rune)
+		n.IsInt = true
+		n.Uint64 = uint64(rune)
+		n.IsUint = true
+		n.Float64 = float64(rune) // odd but those are the rules.
+		n.IsFloat = true
+		return n, nil
+	case itemComplex:
+		// fmt.Sscan can parse the pair, so let it do the work.
+		if _, err := fmt.Sscan(text, &n.Complex128); err != nil {
+			return nil, err
+		}
+		n.IsComplex = true
+		n.simplifyComplex()
+		return n, nil
+	}
+	// Imaginary constants can only be complex unless they are zero.
+	if len(text) > 0 && text[len(text)-1] == 'i' {
+		f, err := strconv.ParseFloat(text[:len(text)-1], 64)
+		if err == nil {
+			n.IsComplex = true
+			n.Complex128 = complex(0, f)
+			n.simplifyComplex()
+			return n, nil
+		}
+	}
+	// Do integer test first so we get 0x123 etc.
+	u, err := strconv.ParseUint(text, 0, 64) // will fail for -0; fixed below.
+	if err == nil {
+		n.IsUint = true
+		n.Uint64 = u
+	}
+	i, err := strconv.ParseInt(text, 0, 64)
+	if err == nil {
+		n.IsInt = true
+		n.Int64 = i
+		if i == 0 {
+			n.IsUint = true // in case of -0.
+			n.Uint64 = u
+		}
+	}
+	// If an integer extraction succeeded, promote the float.
+	if n.IsInt {
+		n.IsFloat = true
+		n.Float64 = float64(n.Int64)
+	} else if n.IsUint {
+		n.IsFloat = true
+		n.Float64 = float64(n.Uint64)
+	} else {
+		f, err := strconv.ParseFloat(text, 64)
+		if err == nil {
+			n.IsFloat = true
+			n.Float64 = f
+			// If a floating-point extraction succeeded, extract the int if needed.
+			if !n.IsInt && float64(int64(f)) == f {
+				n.IsInt = true
+				n.Int64 = int64(f)
+			}
+			if !n.IsUint && float64(uint64(f)) == f {
+				n.IsUint = true
+				n.Uint64 = uint64(f)
+			}
+		}
+	}
+	if !n.IsInt && !n.IsUint && !n.IsFloat {
+		return nil, fmt.Errorf("illegal number syntax: %q", text)
+	}
+	return n, nil
+}
+
+// simplifyComplex pulls out any other types that are represented by the complex number.
+// These all require that the imaginary part be zero.
+func (n *NumberNode) simplifyComplex() {
+	n.IsFloat = imag(n.Complex128) == 0
+	if n.IsFloat {
+		n.Float64 = real(n.Complex128)
+		n.IsInt = float64(int64(n.Float64)) == n.Float64
+		if n.IsInt {
+			n.Int64 = int64(n.Float64)
+		}
+		n.IsUint = float64(uint64(n.Float64)) == n.Float64
+		if n.IsUint {
+			n.Uint64 = uint64(n.Float64)
+		}
+	}
+}
+
+func (n *NumberNode) String() string {
+	return n.Text
+}
+
+func (n *NumberNode) tree() *Tree {
+	return n.tr
+}
+
+func (n *NumberNode) Copy() Node {
+	nn := new(NumberNode)
+	*nn = *n // Easy, fast, correct.
+	return nn
+}
+
+// StringNode holds a string constant. The value has been "unquoted".
+type StringNode struct {
+	NodeType
+	Pos
+	tr     *Tree
+	Quoted string // The original text of the string, with quotes.
+	Text   string // The string, after quote processing.
+}
+
+func (t *Tree) newString(pos Pos, orig, text string) *StringNode {
+	return &StringNode{tr: t, NodeType: NodeString, Pos: pos, Quoted: orig, Text: text}
+}
+
+func (s *StringNode) String() string {
+	return s.Quoted
+}
+
+func (s *StringNode) tree() *Tree {
+	return s.tr
+}
+
+func (s *StringNode) Copy() Node {
+	return s.tr.newString(s.Pos, s.Quoted, s.Text)
+}
+
+// endNode represents an {{end}} action.
+// It does not appear in the final parse tree.
+type endNode struct {
+	NodeType
+	Pos
+	tr *Tree
+}
+
+func (t *Tree) newEnd(pos Pos) *endNode {
+	return &endNode{tr: t, NodeType: nodeEnd, Pos: pos}
+}
+
+func (e *endNode) String() string {
+	return "{{end}}"
+}
+
+func (e *endNode) tree() *Tree {
+	return e.tr
+}
+
+func (e *endNode) Copy() Node {
+	return e.tr.newEnd(e.Pos)
+}
+
+// elseNode represents an {{else}} action. Does not appear in the final tree.
+type elseNode struct {
+	NodeType
+	Pos
+	tr   *Tree
+	Line int // The line number in the input (deprecated; kept for compatibility)
+}
+
+func (t *Tree) newElse(pos Pos, line int) *elseNode {
+	return &elseNode{tr: t, NodeType: nodeElse, Pos: pos, Line: line}
+}
+
+func (e *elseNode) Type() NodeType {
+	return nodeElse
+}
+
+func (e *elseNode) String() string {
+	return "{{else}}"
+}
+
+func (e *elseNode) tree() *Tree {
+	return e.tr
+}
+
+func (e *elseNode) Copy() Node {
+	return e.tr.newElse(e.Pos, e.Line)
+}
+
+// BranchNode is the common representation of if, range, and with.
+type BranchNode struct {
+	NodeType
+	Pos
+	tr       *Tree
+	Line     int       // The line number in the input (deprecated; kept for compatibility)
+	Pipe     *PipeNode // The pipeline to be evaluated.
+	List     *ListNode // What to execute if the value is non-empty.
+	ElseList *ListNode // What to execute if the value is empty (nil if absent).
+}
+
+func (b *BranchNode) String() string {
+	name := ""
+	switch b.NodeType {
+	case NodeIf:
+		name = "if"
+	case NodeRange:
+		name = "range"
+	case NodeWith:
+		name = "with"
+	default:
+		panic("unknown branch type")
+	}
+	if b.ElseList != nil {
+		return fmt.Sprintf("{{%s %s}}%s{{else}}%s{{end}}", name, b.Pipe, b.List, b.ElseList)
+	}
+	return fmt.Sprintf("{{%s %s}}%s{{end}}", name, b.Pipe, b.List)
+}
+
+func (b *BranchNode) tree() *Tree {
+	return b.tr
+}
+
+func (b *BranchNode) Copy() Node {
+	switch b.NodeType {
+	case NodeIf:
+		return b.tr.newIf(b.Pos, b.Line, b.Pipe, b.List, b.ElseList)
+	case NodeRange:
+		return b.tr.newRange(b.Pos, b.Line, b.Pipe, b.List, b.ElseList)
+	case NodeWith:
+		return b.tr.newWith(b.Pos, b.Line, b.Pipe, b.List, b.ElseList)
+	default:
+		panic("unknown branch type")
+	}
+}
+
+// IfNode represents an {{if}} action and its commands.
+type IfNode struct {
+	BranchNode
+}
+
+func (t *Tree) newIf(pos Pos, line int, pipe *PipeNode, list, elseList *ListNode) *IfNode {
+	return &IfNode{BranchNode{tr: t, NodeType: NodeIf, Pos: pos, Line: line, Pipe: pipe, List: list, ElseList: elseList}}
+}
+
+func (i *IfNode) Copy() Node {
+	return i.tr.newIf(i.Pos, i.Line, i.Pipe.CopyPipe(), i.List.CopyList(), i.ElseList.CopyList())
+}
+
+// RangeNode represents a {{range}} action and its commands.
+type RangeNode struct {
+	BranchNode
+}
+
+func (t *Tree) newRange(pos Pos, line int, pipe *PipeNode, list, elseList *ListNode) *RangeNode {
+	return &RangeNode{BranchNode{tr: t, NodeType: NodeRange, Pos: pos, Line: line, Pipe: pipe, List: list, ElseList: elseList}}
+}
+
+func (r *RangeNode) Copy() Node {
+	return r.tr.newRange(r.Pos, r.Line, r.Pipe.CopyPipe(), r.List.CopyList(), r.ElseList.CopyList())
+}
+
+// WithNode represents a {{with}} action and its commands.
+type WithNode struct {
+	BranchNode
+}
+
+func (t *Tree) newWith(pos Pos, line int, pipe *PipeNode, list, elseList *ListNode) *WithNode {
+	return &WithNode{BranchNode{tr: t, NodeType: NodeWith, Pos: pos, Line: line, Pipe: pipe, List: list, ElseList: elseList}}
+}
+
+func (w *WithNode) Copy() Node {
+	return w.tr.newWith(w.Pos, w.Line, w.Pipe.CopyPipe(), w.List.CopyList(), w.ElseList.CopyList())
+}
+
+// TemplateNode represents a {{template}} action.
+type TemplateNode struct {
+	NodeType
+	Pos
+	tr   *Tree
+	Line int       // The line number in the input (deprecated; kept for compatibility)
+	Name string    // The name of the template (unquoted).
+	Pipe *PipeNode // The command to evaluate as dot for the template.
+}
+
+func (t *Tree) newTemplate(pos Pos, line int, name string, pipe *PipeNode) *TemplateNode {
+	return &TemplateNode{tr: t, NodeType: NodeTemplate, Pos: pos, Line: line, Name: name, Pipe: pipe}
+}
+
+func (t *TemplateNode) String() string {
+	if t.Pipe == nil {
+		return fmt.Sprintf("{{template %q}}", t.Name)
+	}
+	return fmt.Sprintf("{{template %q %s}}", t.Name, t.Pipe)
+}
+
+func (t *TemplateNode) tree() *Tree {
+	return t.tr
+}
+
+func (t *TemplateNode) Copy() Node {
+	return t.tr.newTemplate(t.Pos, t.Line, t.Name, t.Pipe.CopyPipe())
+}

vendor/github.com/alecthomas/template/parse/parse.go

@@ -0,0 +1,700 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package parse builds parse trees for templates as defined by text/template
+// and html/template. Clients should use those packages to construct templates
+// rather than this one, which provides shared internal data structures not
+// intended for general use.
+package parse
+
+import (
+	"bytes"
+	"fmt"
+	"runtime"
+	"strconv"
+	"strings"
+)
+
+// Tree is the representation of a single parsed template.
+type Tree struct {
+	Name      string    // name of the template represented by the tree.
+	ParseName string    // name of the top-level template during parsing, for error messages.
+	Root      *ListNode // top-level root of the tree.
+	text      string    // text parsed to create the template (or its parent)
+	// Parsing only; cleared after parse.
+	funcs     []map[string]interface{}
+	lex       *lexer
+	token     [3]item // three-token lookahead for parser.
+	peekCount int
+	vars      []string // variables defined at the moment.
+}
+
+// Copy returns a copy of the Tree. Any parsing state is discarded.
+func (t *Tree) Copy() *Tree {
+	if t == nil {
+		return nil
+	}
+	return &Tree{
+		Name:      t.Name,
+		ParseName: t.ParseName,
+		Root:      t.Root.CopyList(),
+		text:      t.text,
+	}
+}
+
+// Parse returns a map from template name to parse.Tree, created by parsing the
+// templates described in the argument string. The top-level template will be
+// given the specified name. If an error is encountered, parsing stops and an
+// empty map is returned with the error.
+func Parse(name, text, leftDelim, rightDelim string, funcs ...map[string]interface{}) (treeSet map[string]*Tree, err error) {
+	treeSet = make(map[string]*Tree)
+	t := New(name)
+	t.text = text
+	_, err = t.Parse(text, leftDelim, rightDelim, treeSet, funcs...)
+	return
+}
+
+// next returns the next token.
+func (t *Tree) next() item {
+	if t.peekCount > 0 {
+		t.peekCount--
+	} else {
+		t.token[0] = t.lex.nextItem()
+	}
+	return t.token[t.peekCount]
+}
+
+// backup backs the input stream up one token.
+func (t *Tree) backup() {
+	t.peekCount++
+}
+
+// backup2 backs the input stream up two tokens.
+// The zeroth token is already there.
+func (t *Tree) backup2(t1 item) {
+	t.token[1] = t1
+	t.peekCount = 2
+}
+
+// backup3 backs the input stream up three tokens
+// The zeroth token is already there.
+func (t *Tree) backup3(t2, t1 item) { // Reverse order: we're pushing back.
+	t.token[1] = t1
+	t.token[2] = t2
+	t.peekCount = 3
+}
+
+// peek returns but does not consume the next token.
+func (t *Tree) peek() item {
+	if t.peekCount > 0 {
+		return t.token[t.peekCount-1]
+	}
+	t.peekCount = 1
+	t.token[0] = t.lex.nextItem()
+	return t.token[0]
+}
+
+// nextNonSpace returns the next non-space token.
+func (t *Tree) nextNonSpace() (token item) {
+	for {
+		token = t.next()
+		if token.typ != itemSpace {
+			break
+		}
+	}
+	return token
+}
+
+// peekNonSpace returns but does not consume the next non-space token.
+func (t *Tree) peekNonSpace() (token item) {
+	for {
+		token = t.next()
+		if token.typ != itemSpace {
+			break
+		}
+	}
+	t.backup()
+	return token
+}
+
+// Parsing.
+
+// New allocates a new parse tree with the given name.
+func New(name string, funcs ...map[string]interface{}) *Tree {
+	return &Tree{
+		Name:  name,
+		funcs: funcs,
+	}
+}
+
+// ErrorContext returns a textual representation of the location of the node in the input text.
+// The receiver is only used when the node does not have a pointer to the tree inside,
+// which can occur in old code.
+func (t *Tree) ErrorContext(n Node) (location, context string) {
+	pos := int(n.Position())
+	tree := n.tree()
+	if tree == nil {
+		tree = t
+	}
+	text := tree.text[:pos]
+	byteNum := strings.LastIndex(text, "\n")
+	if byteNum == -1 {
+		byteNum = pos // On first line.
+	} else {
+		byteNum++ // After the newline.
+		byteNum = pos - byteNum
+	}
+	lineNum := 1 + strings.Count(text, "\n")
+	context = n.String()
+	if len(context) > 20 {
+		context = fmt.Sprintf("%.20s...", context)
+	}
+	return fmt.Sprintf("%s:%d:%d", tree.ParseName, lineNum, byteNum), context
+}
+
+// errorf formats the error and terminates processing.
+func (t *Tree) errorf(format string, args ...interface{}) {
+	t.Root = nil
+	format = fmt.Sprintf("template: %s:%d: %s", t.ParseName, t.lex.lineNumber(), format)
+	panic(fmt.Errorf(format, args...))
+}
+
+// error terminates processing.
+func (t *Tree) error(err error) {
+