when a new directory is detected watch the entire subtree (#3)

* update to latest fsnotify and alpinelinux
* add debug to watch for possible missing fsnotify events
* excise dead code
* WatchFolderRecursive and RecursiveWatcher.Run race for fsnotify Events causing inconsistent behavior RecursiveWatcher.Files had no receiver so RecursiveWatcher.Run eventually deadlocks
* when a new directory detected watch the entire subtree
* test creating directory for RecursiveWatcher

Author: jkt628

.dockerignore

@@ -0,0 +1,5 @@
+.dockerignore
+Dockerfile
+.git*
+api-gateway-config-supervisor
+*.md

.gitignore

@@ -1,2 +1,3 @@
 /bin
-/pkg
+/pkg
+api-gateway-config-supervisor

Dockerfile

@@ -6,46 +6,38 @@
 #
 FROM alpine:latest
 
-ENV GOPATH /usr/lib/go/bin
-ENV GOBIN  /usr/lib/go/bin
-ENV PATH   $PATH:/usr/lib/go/bin
+ENV GOPATH=/tmp/go \
+    GOBIN=/usr/lib/go/bin \
+    PATH=$PATH:/usr/lib/go/bin
 
+COPY . ${GOPATH}/src/github.com/adobe-apiplatform/api-gateway-config-supervisor
 
-RUN mkdir -p /tmp/go
-ADD . /tmp/go
-RUN echo "http://dl-4.alpinelinux.org/alpine/edge/community" >> /etc/apk/repositories \
+RUN echo " installing aws-cli ..." \
     && apk update \
-    && apk add make git go \
+    && apk add python \
+    && apk add py-pip \
+    && pip install --upgrade pip \
+    && pip install awscli \
+    && apk del py-pip \
 
     && echo " building local project ... " \
-    && cd /tmp/go \
+    && apk add --virtual .build-deps make git gcc libc-dev go \
+    && cd ${GOPATH}/src/github.com/adobe-apiplatform/api-gateway-config-supervisor \
     && make setup \
-    && mkdir -p /tmp/go/Godeps/_workspace \
-    && ln -s /tmp/go/vendor /tmp/go/Godeps/_workspace/src \
-    && mkdir -p /tmp/go-src/src/github.com/adobe-apiplatform \
-    && ln -s /tmp/go /tmp/go-src/src/github.com/adobe-apiplatform/api-gateway-config-supervisor \
-    && GOPATH=/tmp/go/vendor:/tmp/go-src CGO_ENABLED=0 GOOS=linux /usr/lib/go/bin/godep  go test \
-    && GOPATH=/tmp/go/vendor:/tmp/go-src CGO_ENABLED=0 GOOS=linux /usr/lib/go/bin/godep  go build -ldflags "-s" -a -installsuffix cgo -o api-gateway-config-supervisor ./ \
-    && cp /tmp/go/api-gateway-config-supervisor /usr/lib/go/bin \
+    && godep  go test \
+    && godep  go build -ldflags "-s" -a -installsuffix cgo -o api-gateway-config-supervisor ./ \
+    && cp ${GOPATH}/src/github.com/adobe-apiplatform/api-gateway-config-supervisor/api-gateway-config-supervisor ${GOBIN} \
 
     && echo "installing rclone sync ... " \
     && go get github.com/ncw/rclone \
 
     && echo " cleaning up ... " \
-    && rm -rf /usr/lib/go/bin/src \
-    && rm -rf /tmp/go \
-    && rm -rf /tmp/api-gateway-config-supervisor* \
-    && rm -rf /tmp/go-src \
-    && rm -rf /usr/lib/go/bin/pkg/ \
-    && rm -rf /usr/lib/go/bin/godep \
-    && apk del make git go \
+    && rm -rf ${GOBIN}/src \
+       	      ${GOPATH} \
+    	      /tmp/api-gateway-config-supervisor* \
+    	      ${GOBIN}/pkg/ \
+    	      ${GOBIN}/godep \
+    && apk del .build-deps \
     && rm -rf /var/cache/apk/*
 
-RUN echo " installing aws-cli ..." \
-    && apk update \
-    && apk add python \
-    && apk add py-pip \
-    && pip install --upgrade pip \
-    && pip install awscli
-
-ENTRYPOINT ["api-gateway-config-supervisor"]
+ENTRYPOINT ["api-gateway-config-supervisor"]

Godeps/Godeps.json

@@ -1,6 +1,7 @@
 GOPATH ?= `pwd`
 GOBIN ?= `pwd`/bin
 GOOS ?= $(`uname -a | awk '{print tolower($1)}'`)
+.PHONY: setup install test format static docker docker-ssh
 
 setup:
 	go get github.com/tools/godep
@@ -24,6 +25,5 @@ static:
 docker:
 	docker build -t adobeapiplatform/api-gateway-config-supervisor .
 
-.PHONY: docker-ssh
 docker-ssh:
 	docker run -ti --entrypoint='/bin/sh' adobeapiplatform/api-gateway-config-supervisor:latest

Makefile

@@ -29,6 +29,7 @@ var (
 	syncFolder   = pflag.StringP("sync-folder", "", "~/tmp/api-gateway-config", "The folder to watch for changes.")
 	reloadCmd    = pflag.StringP("reload-cmd", "", "echo reload-cmd not defined", "Command used to reload the gateway")
 	httpAddr     = pflag.StringP("http-addr", "", "127.0.0.1:8888", "Http Address exposing a /health-check for the sync process")
+	debug        = pflag.BoolP("debug", "v", false, "Print extra debug information")
 	status       = sync.GetStatusInstance()
 )
 
@@ -79,7 +80,7 @@ func checkForReload() {
 
 //watches for changes in the syncFolder, execute reloadCmd when there are changes
 func watchForFSChanges() {
-	c := sync.WatchFolderRecursive(*syncFolder)
+	c := sync.WatchFolderRecursive(*syncFolder, *debug)
 	for {
 		select {
 		case file := <-c:

config-supervisor.go

@@ -26,6 +26,9 @@ func setup(t *testing.T) (tempdir string) {
 	// setup a sync interval for the test
 	var sync_interval = time.Duration(time.Second * 1)
 	syncInterval = &sync_interval
+	// setup extra debug information
+	debugOn := true
+	debug = &debugOn
 	return tmpDir
 }
 
@@ -66,8 +69,12 @@ func TestThatReloadCommandExecutesOnFsChanges(t *testing.T) {
 	// wait for some time to init
 	time.Sleep(500 * time.Millisecond)
 
-	//modifyFS: create a new file
-	f1, err := createFile(t, tmpDir, "new-file-content")
+	//modifyFS: create a new directory and file
+	dir, err := ioutil.TempDir(tmpDir, "new-dir-")
+	if err != nil {
+		t.Fatal(err)
+	}
+	f1, err := createFile(t, dir, "new-file-content")
 	if err != nil {
 		t.Fatal(err)
 	}

config-supervisor_test.go

@@ -13,7 +13,7 @@ import (
 )
 
 type RecursiveWatcher struct {
-	*fsnotify.Watcher
+	fsw     *fsnotify.Watcher
 	Files   chan string
 	Folders chan string
 }
@@ -37,7 +37,7 @@ func NewRecursiveWatcher(path string) (*RecursiveWatcher, error) {
 	if err != nil {
 		return nil, err
 	}
-	rw := &RecursiveWatcher{Watcher: watcher}
+	rw := &RecursiveWatcher{fsw: watcher}
 
 	rw.Files = make(chan string, 10)
 	rw.Folders = make(chan string, len(folders))
@@ -49,7 +49,7 @@ func NewRecursiveWatcher(path string) (*RecursiveWatcher, error) {
 }
 
 func (watcher *RecursiveWatcher) AddFolder(folder string) {
-	err := watcher.Add(folder)
+	err := watcher.fsw.Add(folder)
 	if err != nil {
 		log.Println("Error watching: ", folder, err)
 	}
@@ -60,7 +60,10 @@ func (watcher *RecursiveWatcher) Run(debug bool) {
 	go func() {
 		for {
 			select {
-			case event := <-watcher.Events:
+			case event := <-watcher.fsw.Events:
+				if debug {
+					log.Println("Event: ", event)
+				}
 				// create a file/directory
 				if event.Op&fsnotify.Create == fsnotify.Create {
 					fi, err := os.Stat(event.Name)
@@ -73,8 +76,8 @@ func (watcher *RecursiveWatcher) Run(debug bool) {
 						if debug {
 							DebugMessage("Detected new directory %s", event.Name)
 						}
-						if !shouldIgnoreFile(filepath.Base(event.Name)) {
-							watcher.AddFolder(event.Name)
+						for _, folder := range Subfolders(event.Name) {
+							watcher.AddFolder(folder)
 						}
 					} else {
 						if debug {
@@ -92,7 +95,7 @@ func (watcher *RecursiveWatcher) Run(debug bool) {
 					watcher.Files <- event.Name
 				}
 
-			case err := <-watcher.Errors:
+			case err := <-watcher.fsw.Errors:
 				log.Println("error", err)
 			}
 		}

sync/recursiveWatcher.go

@@ -7,10 +7,9 @@ import (
 	"os"
 	"os/exec"
 	"strings"
-	"sync"
 )
 
-func executeCmd(cmd string, wg *sync.WaitGroup) {
+func executeCmd(cmd string) {
 	// splitting head => g++ parts => rest of the command
 	parts := strings.Fields(cmd)
 	head := parts[0]
@@ -56,13 +55,9 @@ func executeCmd(cmd string, wg *sync.WaitGroup) {
 	}
 
 	log.Println("done")
-	wg.Done() // Need to signal to waitgroup that this goroutine is done
 }
 
 func Execute(syncCmd string) {
 	log.Println("Executing sync cmd:", syncCmd)
-	wg := new(sync.WaitGroup)
-	wg.Add(1)
-	executeCmd(syncCmd, wg)
-	wg.Wait()
+	executeCmd(syncCmd)
 }

sync/runner.go

@@ -2,34 +2,26 @@ package sync
 
 import (
 	"github.com/koyachi/go-term-ansicolor/ansicolor"
-	"gopkg.in/fsnotify.v1"
 	"log"
 )
 
-type FSWatcher struct {
-	*fsnotify.Watcher
-	Files   chan string
-	Folders chan string
-	Changes <-chan string
-}
-
 // Watches the specific folder for changes
 // When a change happens it triggers a notification on a channel
-func WatchFolderRecursive(folder string) <-chan string {
+func WatchFolderRecursive(folder string, debug bool) <-chan string {
 	done := make(chan string)
 	go func() {
 		watcher, err := NewRecursiveWatcher(folder)
 		if err != nil {
 			log.Fatal(err)
 		}
-		watcher.Run(false)
-		defer watcher.Close()
+		watcher.Run(debug)
+		defer watcher.fsw.Close()
 
 		for {
 			select {
-			case event := <-watcher.Events:
-				done <- event.Name
-				log.Println(ansicolor.IntenseBlack("FS Changed"), ansicolor.Underline(event.Name))
+			case file := <-watcher.Files:
+				done <- file
+				log.Println(ansicolor.IntenseBlack("FS Changed"), ansicolor.Underline(file))
 			case folder := <-watcher.Folders:
 				log.Println(ansicolor.Yellow("Watching path"), ansicolor.Yellow(folder))
 			}