diff --git a/server/v1/watch_key_handler.go b/server/v1/watch_key_handler.go index 67a0c5f04..a7e6b798a 100644 --- a/server/v1/watch_key_handler.go +++ b/server/v1/watch_key_handler.go @@ -25,11 +25,11 @@ func WatchKeyHandler(w http.ResponseWriter, req *http.Request, s Server) error { } // Start the watcher on the store. - c, err := s.Store().Watch(key, false, sinceIndex) + watcher, err := s.Store().NewWatcher(key, false, sinceIndex) if err != nil { return etcdErr.NewError(500, key, s.Store().Index()) } - event := <-c + event := <-watcher.EventChan // Convert event to a response and write to client. b, _ := json.Marshal(event.Response(s.Store().Index())) diff --git a/server/v2/get_handler.go b/server/v2/get_handler.go index 9a67ea2ae..031ff449e 100644 --- a/server/v2/get_handler.go +++ b/server/v2/get_handler.go @@ -55,7 +55,7 @@ func GetHandler(w http.ResponseWriter, req *http.Request, s Server) error { } // Start the watcher on the store. - eventChan, err := s.Store().Watch(key, recursive, sinceIndex) + watcher, err := s.Store().NewWatcher(key, recursive, sinceIndex) if err != nil { return etcdErr.NewError(500, key, s.Store().Index()) } @@ -65,8 +65,9 @@ func GetHandler(w http.ResponseWriter, req *http.Request, s Server) error { select { case <-closeChan: + watcher.Remove() return nil - case event = <-eventChan: + case event = <-watcher.EventChan: } } else { //get diff --git a/store/store.go b/store/store.go index 08d585056..15c045d41 100644 --- a/store/store.go +++ b/store/store.go @@ -52,7 +52,8 @@ type Store interface { value string, expireTime time.Time) (*Event, error) Delete(nodePath string, recursive, dir bool) (*Event, error) CompareAndDelete(nodePath string, prevValue string, prevIndex uint64) (*Event, error) - Watch(prefix string, recursive bool, sinceIndex uint64) (<-chan *Event, error) + + NewWatcher(prefix string, recursive bool, sinceIndex uint64) (*Watcher, error) Save() ([]byte, error) Recovery(state []byte) error @@ -340,21 +341,21 @@ func (s *store) CompareAndDelete(nodePath string, prevValue string, prevIndex ui return e, nil } -func (s *store) Watch(key string, recursive bool, sinceIndex uint64) (<-chan *Event, error) { +func (s *store) NewWatcher(key string, recursive bool, sinceIndex uint64) (*Watcher, error) { key = path.Clean(path.Join("/", key)) nextIndex := s.CurrentIndex + 1 s.worldLock.RLock() defer s.worldLock.RUnlock() - var c <-chan *Event + var w *Watcher var err *etcdErr.Error if sinceIndex == 0 { - c, err = s.WatcherHub.watch(key, recursive, nextIndex) + w, err = s.WatcherHub.watch(key, recursive, nextIndex) } else { - c, err = s.WatcherHub.watch(key, recursive, sinceIndex) + w, err = s.WatcherHub.watch(key, recursive, sinceIndex) } if err != nil { @@ -364,7 +365,7 @@ func (s *store) Watch(key string, recursive bool, sinceIndex uint64) (<-chan *Ev return nil, err } - return c, nil + return w, nil } // walk function walks all the nodePath and apply the walkFunc on each directory diff --git a/store/store_test.go b/store/store_test.go index b29fea627..4d71c91b9 100644 --- a/store/store_test.go +++ b/store/store_test.go @@ -446,7 +446,8 @@ func TestStoreCompareAndSwapPrevIndexFailsIfNotMatch(t *testing.T) { // Ensure that the store can watch for key creation. func TestStoreWatchCreate(t *testing.T) { s := newStore() - c, _ := s.Watch("/foo", false, 0) + w, _ := s.NewWatcher("/foo", false, 0) + c := w.EventChan s.Create("/foo", false, "bar", false, Permanent) e := nbselect(c) assert.Equal(t, e.Action, "create", "") @@ -458,9 +459,9 @@ func TestStoreWatchCreate(t *testing.T) { // Ensure that the store can watch for recursive key creation. func TestStoreWatchRecursiveCreate(t *testing.T) { s := newStore() - c, _ := s.Watch("/foo", true, 0) + w, _ := s.NewWatcher("/foo", true, 0) s.Create("/foo/bar", false, "baz", false, Permanent) - e := nbselect(c) + e := nbselect(w.EventChan) assert.Equal(t, e.Action, "create", "") assert.Equal(t, e.Node.Key, "/foo/bar", "") } @@ -469,9 +470,9 @@ func TestStoreWatchRecursiveCreate(t *testing.T) { func TestStoreWatchUpdate(t *testing.T) { s := newStore() s.Create("/foo", false, "bar", false, Permanent) - c, _ := s.Watch("/foo", false, 0) + w, _ := s.NewWatcher("/foo", false, 0) s.Update("/foo", "baz", Permanent) - e := nbselect(c) + e := nbselect(w.EventChan) assert.Equal(t, e.Action, "update", "") assert.Equal(t, e.Node.Key, "/foo", "") } @@ -480,9 +481,9 @@ func TestStoreWatchUpdate(t *testing.T) { func TestStoreWatchRecursiveUpdate(t *testing.T) { s := newStore() s.Create("/foo/bar", false, "baz", false, Permanent) - c, _ := s.Watch("/foo", true, 0) + w, _ := s.NewWatcher("/foo", true, 0) s.Update("/foo/bar", "baz", Permanent) - e := nbselect(c) + e := nbselect(w.EventChan) assert.Equal(t, e.Action, "update", "") assert.Equal(t, e.Node.Key, "/foo/bar", "") } @@ -491,9 +492,9 @@ func TestStoreWatchRecursiveUpdate(t *testing.T) { func TestStoreWatchDelete(t *testing.T) { s := newStore() s.Create("/foo", false, "bar", false, Permanent) - c, _ := s.Watch("/foo", false, 0) + w, _ := s.NewWatcher("/foo", false, 0) s.Delete("/foo", false, false) - e := nbselect(c) + e := nbselect(w.EventChan) assert.Equal(t, e.Action, "delete", "") assert.Equal(t, e.Node.Key, "/foo", "") } @@ -502,9 +503,9 @@ func TestStoreWatchDelete(t *testing.T) { func TestStoreWatchRecursiveDelete(t *testing.T) { s := newStore() s.Create("/foo/bar", false, "baz", false, Permanent) - c, _ := s.Watch("/foo", true, 0) + w, _ := s.NewWatcher("/foo", true, 0) s.Delete("/foo/bar", false, false) - e := nbselect(c) + e := nbselect(w.EventChan) assert.Equal(t, e.Action, "delete", "") assert.Equal(t, e.Node.Key, "/foo/bar", "") } @@ -513,9 +514,9 @@ func TestStoreWatchRecursiveDelete(t *testing.T) { func TestStoreWatchCompareAndSwap(t *testing.T) { s := newStore() s.Create("/foo", false, "bar", false, Permanent) - c, _ := s.Watch("/foo", false, 0) + w, _ := s.NewWatcher("/foo", false, 0) s.CompareAndSwap("/foo", "bar", 0, "baz", Permanent) - e := nbselect(c) + e := nbselect(w.EventChan) assert.Equal(t, e.Action, "compareAndSwap", "") assert.Equal(t, e.Node.Key, "/foo", "") } @@ -524,9 +525,9 @@ func TestStoreWatchCompareAndSwap(t *testing.T) { func TestStoreWatchRecursiveCompareAndSwap(t *testing.T) { s := newStore() s.Create("/foo/bar", false, "baz", false, Permanent) - c, _ := s.Watch("/foo", true, 0) + w, _ := s.NewWatcher("/foo", true, 0) s.CompareAndSwap("/foo/bar", "baz", 0, "bat", Permanent) - e := nbselect(c) + e := nbselect(w.EventChan) assert.Equal(t, e.Action, "compareAndSwap", "") assert.Equal(t, e.Node.Key, "/foo/bar", "") } @@ -544,15 +545,16 @@ func TestStoreWatchExpire(t *testing.T) { s.Create("/foo", false, "bar", false, time.Now().Add(500*time.Millisecond)) s.Create("/foofoo", false, "barbarbar", false, time.Now().Add(500*time.Millisecond)) - c, _ := s.Watch("/", true, 0) + w, _ := s.NewWatcher("/", true, 0) + c := w.EventChan e := nbselect(c) assert.Nil(t, e, "") time.Sleep(600 * time.Millisecond) e = nbselect(c) assert.Equal(t, e.Action, "expire", "") assert.Equal(t, e.Node.Key, "/foo", "") - c, _ = s.Watch("/", true, 4) - e = nbselect(c) + w, _ = s.NewWatcher("/", true, 4) + e = nbselect(w.EventChan) assert.Equal(t, e.Action, "expire", "") assert.Equal(t, e.Node.Key, "/foofoo", "") } diff --git a/store/watcher.go b/store/watcher.go index 004ca9222..06060c03b 100644 --- a/store/watcher.go +++ b/store/watcher.go @@ -16,15 +16,16 @@ limitations under the License. package store -type watcher struct { - eventChan chan *Event +type Watcher struct { + EventChan chan *Event recursive bool sinceIndex uint64 + Remove func() } // notify function notifies the watcher. If the watcher interests in the given path, // the function will return true. -func (w *watcher) notify(e *Event, originalPath bool, deleted bool) bool { +func (w *Watcher) notify(e *Event, originalPath bool, deleted bool) bool { // watcher is interested the path in three cases and under one condition // the condition is that the event happens after the watcher's sinceIndex @@ -41,7 +42,7 @@ func (w *watcher) notify(e *Event, originalPath bool, deleted bool) bool { // For example a watcher is watching at "/foo/bar". And we deletes "/foo". The watcher // should get notified even if "/foo" is not the path it is watching. if (w.recursive || originalPath || deleted) && e.Index() >= w.sinceIndex { - w.eventChan <- e + w.EventChan <- e return true } return false diff --git a/store/watcher_hub.go b/store/watcher_hub.go index 9721ffdb0..a8865d49d 100644 --- a/store/watcher_hub.go +++ b/store/watcher_hub.go @@ -36,41 +36,48 @@ func newWatchHub(capacity int) *watcherHub { // If recursive is true, the first change after index under key will be sent to the event channel. // If recursive is false, the first change after index at key will be sent to the event channel. // If index is zero, watch will start from the current index + 1. -func (wh *watcherHub) watch(key string, recursive bool, index uint64) (<-chan *Event, *etcdErr.Error) { +func (wh *watcherHub) watch(key string, recursive bool, index uint64) (*Watcher, *etcdErr.Error) { event, err := wh.EventHistory.scan(key, recursive, index) if err != nil { return nil, err } - eventChan := make(chan *Event, 1) // use a buffered channel - - if event != nil { - eventChan <- event - - return eventChan, nil - } - - w := &watcher{ - eventChan: eventChan, + w := &Watcher{ + EventChan: make(chan *Event, 1), // use a buffered channel recursive: recursive, sinceIndex: index, } + if event != nil { + w.EventChan <- event + + return w, nil + } + l, ok := wh.watchers[key] + var elem *list.Element + if ok { // add the new watcher to the back of the list - l.PushBack(w) + elem = l.PushBack(w) } else { // create a new list and add the new watcher - l := list.New() - l.PushBack(w) + l = list.New() + elem = l.PushBack(w) wh.watchers[key] = l } + w.Remove = func() { + l.Remove(elem) + if l.Len() == 0 { + delete(wh.watchers, key) + } + } + atomic.AddInt64(&wh.count, 1) - return eventChan, nil + return w, nil } // notify function accepts an event and notify to the watchers. @@ -109,7 +116,7 @@ func (wh *watcherHub) notifyWatchers(e *Event, path string, deleted bool) { next := curr.Next() // save reference to the next one in the list - w, _ := curr.Value.(*watcher) + w, _ := curr.Value.(*Watcher) if w.notify(e, e.Node.Key == path, deleted) { diff --git a/store/watcher_test.go b/store/watcher_test.go index 7d76d83d7..2600fa161 100644 --- a/store/watcher_test.go +++ b/store/watcher_test.go @@ -23,10 +23,11 @@ import ( func TestWatcher(t *testing.T) { s := newStore() wh := s.WatcherHub - c, err := wh.watch("/foo", true, 1) + w, err := wh.watch("/foo", true, 1) if err != nil { t.Fatalf("%v", err) } + c := w.EventChan select { case <-c: @@ -45,7 +46,8 @@ func TestWatcher(t *testing.T) { t.Fatal("recv != send") } - c, _ = wh.watch("/foo", false, 2) + w, _ = wh.watch("/foo", false, 2) + c = w.EventChan e = newEvent(Create, "/foo/bar", 2, 2) @@ -69,7 +71,8 @@ func TestWatcher(t *testing.T) { } // ensure we are doing exact matching rather than prefix matching - c, _ = wh.watch("/fo", true, 1) + w, _ = wh.watch("/fo", true, 1) + c = w.EventChan select { case re = <-c: