From 8ca1a2097d3036d3cc11dd751ad010e0f41ac58a Mon Sep 17 00:00:00 2001
From: Chakib Ben Ziane <contact@blob42.xyz>
Date: Thu, 14 Jun 2018 02:30:18 +0200
Subject: [PATCH] wip need to use queue for firefox watcher

---
 browsers.go | 14 +++++++++++---
 firefox.go  | 11 +++++++++++
 utils.go    | 21 ++++++++++++++-------
 watcher.go  | 14 ++++++--------
 4 files changed, 42 insertions(+), 18 deletions(-)

diff --git a/browsers.go b/browsers.go
index f92cbc6..2e9792c 100644
--- a/browsers.go
+++ b/browsers.go
@@ -24,6 +24,9 @@ const (
 	TFirefox
 )
 
+// Channel parameters
+const EventsChanLen = 1000
+
 // Used to store bookmark paths and other
 // data related to a particular browser kind
 type BrowserPaths struct {
@@ -54,9 +57,10 @@ type IBrowser interface {
 //
 // `BufferDB`: sqlite buffer used across jobs
 type BaseBrowser struct {
-	watcher *fsnotify.Watcher
-	baseDir string
-	bkFile  string
+	watcher    *fsnotify.Watcher
+	eventsChan chan fsnotify.Event
+	baseDir    string
+	bkFile     string
 
 	// In memory sqlite db (named `memcache`).
 	// Used to keep a browser's state of bookmarks across jobs.
@@ -103,6 +107,10 @@ func (bw *BaseBrowser) GetPath() string {
 	return path.Join(bw.baseDir, bw.bkFile)
 }
 
+func (bw *BaseBrowser) EventsChan() chan fsnotify.Event {
+	return bw.eventsChan
+}
+
 func (bw *BaseBrowser) GetDir() string {
 	return bw.baseDir
 }
diff --git a/firefox.go b/firefox.go
index 1a814eb..b1142c0 100644
--- a/firefox.go
+++ b/firefox.go
@@ -1,5 +1,11 @@
 package main
 
+import (
+	"time"
+
+	"github.com/fsnotify/fsnotify"
+)
+
 var Firefox = BrowserPaths{
 	"places.sqlite",
 	"/home/spike/.mozilla/firefox/p1rrgord.default/",
@@ -17,12 +23,17 @@ func NewFFBrowser() IBrowser {
 	browser.bkFile = Firefox.BookmarkFile
 	browser.Stats = &ParserStats{}
 	browser.NodeTree = &Node{Name: "root", Parent: nil}
+	browser.eventsChan = make(chan fsnotify.Event, EventsChanLen)
 
 	// Across jobs buffer
 	browser.InitBuffer()
 
 	browser.SetupWatcher()
 
+	// Run debouncer to avoid duplicate running of jobs
+	// when a batch of events is received
+	go debouncer(3000*time.Millisecond, browser.eventsChan, browser)
+
 	return browser
 }
 
diff --git a/utils.go b/utils.go
index 6f12f82..27019e9 100644
--- a/utils.go
+++ b/utils.go
@@ -9,16 +9,23 @@ import (
 // TODO
 // Run debounce in it's own thread when the watcher is started
 // It receives a struct{event, func} and runs the func only once in the interval
-func debounce(interval time.Duration, input chan fsnotify.Event, w IWatchable) {
-	var item fsnotify.Event
+func debouncer(interval time.Duration, input chan fsnotify.Event, w IWatchable) {
+	log.Debug("Running debouncer")
+	//var event fsnotify.Event
+
+	ticker := time.NewTicker(interval)
 
 	for {
 		select {
-		case item = <-input:
-			log.Debugf("received an event %v on the spammy events channel", item.Op)
-		case <-time.After(interval):
-			log.Debug("Runngin parse method")
-			w.Run()
+		//case event = <-input:
+		//log.Debugf("received an event %v on the spammy events channel", event.Op)
+
+		//// Run the job
+		////w.Run()
+
+		case <-ticker.C:
+			log.Debugf("debouncer ticker ... events len: %v", len(input))
+			log.Debug("implement a queue ! Should not use channels as queues")
 		}
 	}
 }
diff --git a/watcher.go b/watcher.go
index 2cdd77a..33a5389 100644
--- a/watcher.go
+++ b/watcher.go
@@ -1,8 +1,6 @@
 package main
 
 import (
-	"time"
-
 	"github.com/fsnotify/fsnotify"
 )
 
@@ -15,13 +13,12 @@ type IWatchable interface {
 	Watcher() *fsnotify.Watcher // returns linked watcher
 	GetPath() string            // returns watched path
 	GetDir() string             // returns watched dir
+	EventsChan() chan fsnotify.Event
 }
 
 // Main thread for watching file changes
 func WatcherThread(w IWatchable) {
 
-	spammyEventsChannel := make(chan fsnotify.Event)
-
 	bookmarkPath := w.GetPath()
 	log.Infof("watching %s", bookmarkPath)
 
@@ -46,11 +43,12 @@ func WatcherThread(w IWatchable) {
 			}
 
 			// Firefox keeps the file open and makes changes on it
-			if event.Op&fsnotify.Write == fsnotify.Write &&
-				event.Name == bookmarkPath {
+			// It needs a debouncer
+			if event.Name == bookmarkPath {
 				debugPrint("event: %v | eventName: %v", event.Op, event.Name)
-				go debounce(1000*time.Millisecond, spammyEventsChannel, w)
-				spammyEventsChannel <- event
+				//go debounce(1000*time.Millisecond, spammyEventsChannel, w)
+				ch := w.EventsChan()
+				ch <- event
 				//w.Run()
 			}
 		case err := <-watcher.Errors: