From f8ca35fd77d8265766c9751945afec72d9ef110f Mon Sep 17 00:00:00 2001
From: Xiang Li <xiang.li@coreos.com>
Date: Fri, 7 Jun 2013 11:35:49 -0700
Subject: [PATCH] add notification struct

---
 store.go        |  6 +++++-
 watcher.go      | 48 +++++++++++++++++++++++++++++++-----------------
 watcher_test.go | 22 +++++++++++++++++-----
 3 files changed, 53 insertions(+), 23 deletions(-)

diff --git a/store.go b/store.go
index bc0d721df..6e61578dd 100644
--- a/store.go
+++ b/store.go
@@ -26,14 +26,16 @@ func (s *Store) Set(key string, value string) (string, bool) {
 	if ok {
 		s.Nodes[key] = value
 		return oldValue, true
+
 	} else {
+
 		s.Nodes[key] = value
 		return "", false
 	}
 
 }
 
-// get the node of the key
+// get the value of the key
 func (s *Store) Get(key string) (string, error) {
 	key = path.Clean(key)
 
@@ -60,6 +62,7 @@ func (s *Store) Delete(key string) (string, error) {
 	}
 }
 
+// save the current state of the storage system
 func (s *Store) Save() ([]byte, error) {
 	b, err := json.Marshal(s)
 	if err != nil {
@@ -68,6 +71,7 @@ func (s *Store) Save() ([]byte, error) {
 	return b, nil
 }
 
+// recovery the state of the stroage system from a previous state
 func (s *Store) Recovery(state []byte) error {
 	err := json.Unmarshal(state, s)
 	return err
diff --git a/watcher.go b/watcher.go
index 3760ec401..2799aa744 100644
--- a/watcher.go
+++ b/watcher.go
@@ -6,43 +6,44 @@ import (
 	"fmt"
 	)
 
+// CONSTANTS
+
 type Watcher struct {
-	chanMap map[string][]chan int
+	chanMap map[string][]chan Notification
+}
+
+type Notification struct {
+	action int 
+	key	string
+	oldValue string
+	newValue string
 }
 
 func createWatcher() *Watcher {
 	w := new(Watcher)
-	w.chanMap = make(map[string][]chan int)
+	w.chanMap = make(map[string][]chan Notification)
 	return w
 }
 
-func (w *Watcher) add(prefix string, c chan int) error {
+func (w *Watcher) add(prefix string, c chan Notification, f func(chan Notification)) 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] = make([]chan Notification, 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)
+
+	go f(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)
 
@@ -50,17 +51,30 @@ func (w *Watcher) notify(action int, key string, oldValue string, newValue strin
 
 	currPath := "/"
 
+	// walk through all the pathes
 	for _, segment := range segments {
+
 		currPath := path.Join(currPath, segment)
+
 		fmt.Println(currPath)
+
 		chans, ok := w.chanMap[currPath]
+
 		if ok {
 			fmt.Println("found ", currPath)
+
+			n := Notification {action, key, oldValue, newValue}
+			// notify all the watchers
 			for _, c := range chans {
-				c <- 0
+				c <- n
 			}
+
+			// we have notified all the watchers at this path
+			// delete the map
 			delete(w.chanMap, currPath)
 		}
+
 	}
+
 	return nil
 }
\ No newline at end of file
diff --git a/watcher_test.go b/watcher_test.go
index 5a2f1b6dc..2f899b77a 100644
--- a/watcher_test.go
+++ b/watcher_test.go
@@ -2,13 +2,25 @@ package raftd
 
 import (
 	"testing"
+	"fmt"
 )
 
 func TestWatch(t *testing.T) {
 	watcher := createWatcher()
-	c := make(chan int)
-	d := make(chan int)
-	watcher.add("/prefix/", c)
-	watcher.add("/prefix/", d)
+	c := make(chan Notification)
+	d := make(chan Notification)
+	watcher.add("/", c, say)
+	watcher.add("/prefix/", d, say)
 	watcher.notify(0, "/prefix/hihihi", "1", "1")
-}
\ No newline at end of file
+}
+
+func say(c chan Notification) {
+	result := <-c
+
+	if result.action != -1 {
+		fmt.Println("yes")
+	} else {
+		fmt.Println("no")
+	}
+
+}