From 1f57788f161d4508b0a2ce56494a08e14558f661 Mon Sep 17 00:00:00 2001
From: Xiang Li <xiang.li@coreos.com>
Date: Fri, 7 Jun 2013 10:45:33 -0700
Subject: [PATCH] add basic watch implementation

---
 watcher.go      | 66 +++++++++++++++++++++++++++++++++++++++++++++++++
 watcher_test.go | 14 +++++++++++
 2 files changed, 80 insertions(+)
 create mode 100644 watcher.go
 create mode 100644 watcher_test.go

diff --git a/watcher.go b/watcher.go
new file mode 100644
index 000000000..3760ec401
--- /dev/null
+++ b/watcher.go
@@ -0,0 +1,66 @@
+package raftd
+
+import (
+	"path"
+	"strings"
+	"fmt"
+	)
+
+type Watcher struct {
+	chanMap map[string][]chan int
+}
+
+func createWatcher() *Watcher {
+	w := new(Watcher)
+	w.chanMap = make(map[string][]chan int)
+	return w
+}
+
+func (w *Watcher) add(prefix string, c chan int) error {
+
+	prefix = path.Clean(prefix)
+	fmt.Println("Add ", prefix)
+	_, ok := w.chanMap[prefix]
+	if !ok {
+		w.chanMap[prefix] = make([]chan int, 0)
+		w.chanMap[prefix] = append(w.chanMap[prefix], c)
+	} else {
+		w.chanMap[prefix] = append(w.chanMap[prefix], c)
+	}
+	fmt.Println(len(w.chanMap[prefix]), "@", prefix)
+	go wait(c)
+	return nil
+}
+
+func wait(c chan int) {
+	result := <-c
+
+	if result == 0 {
+		fmt.Println("yes")
+	} else {
+		fmt.Println("no")
+	}
+
+}
+
+func (w *Watcher) notify(action int, key string, oldValue string, newValue string) error {
+	key = path.Clean(key)
+
+	segments := strings.Split(key, "/")
+
+	currPath := "/"
+
+	for _, segment := range segments {
+		currPath := path.Join(currPath, segment)
+		fmt.Println(currPath)
+		chans, ok := w.chanMap[currPath]
+		if ok {
+			fmt.Println("found ", currPath)
+			for _, c := range chans {
+				c <- 0
+			}
+			delete(w.chanMap, currPath)
+		}
+	}
+	return nil
+}
\ No newline at end of file
diff --git a/watcher_test.go b/watcher_test.go
new file mode 100644
index 000000000..5a2f1b6dc
--- /dev/null
+++ b/watcher_test.go
@@ -0,0 +1,14 @@
+package raftd
+
+import (
+	"testing"
+)
+
+func TestWatch(t *testing.T) {
+	watcher := createWatcher()
+	c := make(chan int)
+	d := make(chan int)
+	watcher.add("/prefix/", c)
+	watcher.add("/prefix/", d)
+	watcher.notify(0, "/prefix/hihihi", "1", "1")
+}
\ No newline at end of file