Rename watch.Mux -> watch.Broadcaster

A few reasons:
- Mux is already widely used in the codebase to refer to a http handler mux.
- Original meaning of Mux was something which sent a chose one of several inputs to
  and output.  This sends one output to all outputs.  Broadcast captures that idea
  better.
- Aligns with similar class config.Broadcaster (see #2747)

pkg/client/record/event.go

@@ -118,7 +118,7 @@ func GetEvents(f func(*api.Event)) watch.Interface {
 
 const queueLen = 1000
 
-var events = watch.NewMux(queueLen)
+var events = watch.NewBroadcaster(queueLen)
 
 // Event constructs an event from the given information and puts it in the queue for sending.
 // 'object' is the object this event is about. Event will make a reference-- or you may also

pkg/registry/event/rest_test.go

@@ -257,7 +257,7 @@ func TestRESTWatch(t *testing.T) {
 		t.Fatalf("Unexpected error %v", err)
 	}
 	go func() {
-		reg.Mux.Action(watch.Added, eventA)
+		reg.Broadcaster.Action(watch.Added, eventA)
 	}()
 	got := <-wi.ResultChan()
 	if e, a := eventA, got.Object; !reflect.DeepEqual(e, a) {

pkg/registry/registrytest/generic.go

@@ -33,13 +33,13 @@ type GenericRegistry struct {
 	ObjectList runtime.Object
 	sync.Mutex
 
-	Mux *watch.Mux
+	Broadcaster *watch.Broadcaster
 }
 
 func NewGeneric(list runtime.Object) *GenericRegistry {
 	return &GenericRegistry{
 		ObjectList:  list,
-		Mux:        watch.NewMux(0),
+		Broadcaster: watch.NewBroadcaster(0),
 	}
 }
 
@@ -54,7 +54,7 @@ func (r *GenericRegistry) List(ctx api.Context, m generic.Matcher) (runtime.Obje
 
 func (r *GenericRegistry) Watch(ctx api.Context, m generic.Matcher, resourceVersion string) (watch.Interface, error) {
 	// TODO: wire filter down into the mux; it needs access to current and previous state :(
-	return r.Mux.Watch(), nil
+	return r.Broadcaster.Watch(), nil
 }
 
 func (r *GenericRegistry) Get(ctx api.Context, id string) (runtime.Object, error) {
@@ -67,7 +67,7 @@ func (r *GenericRegistry) Create(ctx api.Context, id string, obj runtime.Object)
 	r.Lock()
 	defer r.Unlock()
 	r.Object = obj
-	r.Mux.Action(watch.Added, obj)
+	r.Broadcaster.Action(watch.Added, obj)
 	return r.Err
 }
 
@@ -75,13 +75,13 @@ func (r *GenericRegistry) Update(ctx api.Context, id string, obj runtime.Object)
 	r.Lock()
 	defer r.Unlock()
 	r.Object = obj
-	r.Mux.Action(watch.Modified, obj)
+	r.Broadcaster.Action(watch.Modified, obj)
 	return r.Err
 }
 
 func (r *GenericRegistry) Delete(ctx api.Context, id string) error {
 	r.Lock()
 	defer r.Unlock()
-	r.Mux.Action(watch.Deleted, r.Object)
+	r.Broadcaster.Action(watch.Deleted, r.Object)
 	return r.Err
 }

pkg/registry/registrytest/pod.go

@@ -30,13 +30,13 @@ type PodRegistry struct {
 	Pods *api.PodList
 	sync.Mutex
 
-	mux *watch.Mux
+	broadcaster *watch.Broadcaster
 }
 
 func NewPodRegistry(pods *api.PodList) *PodRegistry {
 	return &PodRegistry{
 		Pods:        pods,
-		mux:  watch.NewMux(0),
+		broadcaster: watch.NewBroadcaster(0),
 	}
 }
 
@@ -64,8 +64,8 @@ func (r *PodRegistry) ListPods(ctx api.Context, selector labels.Selector) (*api.
 }
 
 func (r *PodRegistry) WatchPods(ctx api.Context, resourceVersion string, filter func(*api.Pod) bool) (watch.Interface, error) {
-	// TODO: wire filter down into the mux; it needs access to current and previous state :(
-	return r.mux.Watch(), nil
+	// TODO: wire filter down into the broadcaster; it needs access to current and previous state :(
+	return r.broadcaster.Watch(), nil
 }
 
 func (r *PodRegistry) GetPod(ctx api.Context, podId string) (*api.Pod, error) {
@@ -78,7 +78,7 @@ func (r *PodRegistry) CreatePod(ctx api.Context, pod *api.Pod) error {
 	r.Lock()
 	defer r.Unlock()
 	r.Pod = pod
-	r.mux.Action(watch.Added, pod)
+	r.broadcaster.Action(watch.Added, pod)
 	return r.Err
 }
 
@@ -86,13 +86,13 @@ func (r *PodRegistry) UpdatePod(ctx api.Context, pod *api.Pod) error {
 	r.Lock()
 	defer r.Unlock()
 	r.Pod = pod
-	r.mux.Action(watch.Modified, pod)
+	r.broadcaster.Action(watch.Modified, pod)
 	return r.Err
 }
 
 func (r *PodRegistry) DeletePod(ctx api.Context, podId string) error {
 	r.Lock()
 	defer r.Unlock()
-	r.mux.Action(watch.Deleted, r.Pod)
+	r.broadcaster.Action(watch.Deleted, r.Pod)
 	return r.Err
 }

pkg/watch/mux.go

@@ -22,25 +22,25 @@ import (
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/runtime"
 )
 
-// Mux distributes event notifications among any number of watchers. Every event
+// Broadcaster distributes event notifications among any number of watchers. Every event
 // is delivered to every watcher.
-type Mux struct {
+type Broadcaster struct {
 	lock sync.Mutex
 
-	watchers    map[int64]*muxWatcher
+	watchers    map[int64]*broadcasterWatcher
 	nextWatcher int64
 
 	incoming chan Event
 }
 
-// NewMux creates a new Mux. queueLength is the maximum number of events to queue.
+// NewBroadcaster creates a new Broadcaster. queueLength is the maximum number of events to queue.
 // When queueLength is 0, Action will block until any prior event has been
 // completely distributed. It is guaranteed that events will be distibuted in the
 // order in which they ocurr, but the order in which a single event is distributed
 // among all of the watchers is unspecified.
-func NewMux(queueLength int) *Mux {
-	m := &Mux{
-		watchers: map[int64]*muxWatcher{},
+func NewBroadcaster(queueLength int) *Broadcaster {
+	m := &Broadcaster{
+		watchers: map[int64]*broadcasterWatcher{},
 		incoming: make(chan Event, queueLength),
 	}
 	go m.loop()
@@ -50,12 +50,12 @@ func NewMux(queueLength int) *Mux {
 // Watch adds a new watcher to the list and returns an Interface for it.
 // Note: new watchers will only receive new events. They won't get an entire history
 // of previous events.
-func (m *Mux) Watch() Interface {
+func (m *Broadcaster) Watch() Interface {
 	m.lock.Lock()
 	defer m.lock.Unlock()
 	id := m.nextWatcher
 	m.nextWatcher++
-	w := &muxWatcher{
+	w := &broadcasterWatcher{
 		result:  make(chan Event),
 		stopped: make(chan struct{}),
 		id:      id,
@@ -66,7 +66,7 @@ func (m *Mux) Watch() Interface {
 }
 
 // stopWatching stops the given watcher and removes it from the list.
-func (m *Mux) stopWatching(id int64) {
+func (m *Broadcaster) stopWatching(id int64) {
 	m.lock.Lock()
 	defer m.lock.Unlock()
 	w, ok := m.watchers[id]
@@ -79,7 +79,7 @@ func (m *Mux) stopWatching(id int64) {
 }
 
 // closeAll disconnects all watchers (presumably in response to a Shutdown call).
-func (m *Mux) closeAll() {
+func (m *Broadcaster) closeAll() {
 	m.lock.Lock()
 	defer m.lock.Unlock()
 	for _, w := range m.watchers {
@@ -87,24 +87,24 @@ func (m *Mux) closeAll() {
 	}
 	// Delete everything from the map, since presence/absence in the map is used
 	// by stopWatching to avoid double-closing the channel.
-	m.watchers = map[int64]*muxWatcher{}
+	m.watchers = map[int64]*broadcasterWatcher{}
 }
 
 // Action distributes the given event among all watchers.
-func (m *Mux) Action(action EventType, obj runtime.Object) {
+func (m *Broadcaster) Action(action EventType, obj runtime.Object) {
 	m.incoming <- Event{action, obj}
 }
 
 // Shutdown disconnects all watchers (but any queued events will still be distributed).
 // You must not call Action after calling Shutdown.
-func (m *Mux) Shutdown() {
+func (m *Broadcaster) Shutdown() {
 	close(m.incoming)
 }
 
 // loop recieves from m.incoming and distributes to all watchers.
-func (m *Mux) loop() {
+func (m *Broadcaster) loop() {
 	// Deliberately not catching crashes here. Yes, bring down the process if there's a
-	// bug in watch.Mux.
+	// bug in watch.Broadcaster.
 	for {
 		event, ok := <-m.incoming
 		if !ok {
@@ -116,7 +116,7 @@ func (m *Mux) loop() {
 }
 
 // distribute sends event to all watchers. Blocking.
-func (m *Mux) distribute(event Event) {
+func (m *Broadcaster) distribute(event Event) {
 	m.lock.Lock()
 	defer m.lock.Unlock()
 	for _, w := range m.watchers {
@@ -127,22 +127,22 @@ func (m *Mux) distribute(event Event) {
 	}
 }
 
-// muxWatcher handles a single watcher of a mux
-type muxWatcher struct {
+// broadcasterWatcher handles a single watcher of a broadcaster
+type broadcasterWatcher struct {
 	result  chan Event
 	stopped chan struct{}
 	stop    sync.Once
 	id      int64
-	m       *Mux
+	m       *Broadcaster
 }
 
 // ResultChan returns a channel to use for waiting on events.
-func (mw *muxWatcher) ResultChan() <-chan Event {
+func (mw *broadcasterWatcher) ResultChan() <-chan Event {
 	return mw.result
 }
 
 // Stop stops watching and removes mw from its list.
-func (mw *muxWatcher) Stop() {
+func (mw *broadcasterWatcher) Stop() {
 	mw.stop.Do(func() {
 		close(mw.stopped)
 		mw.m.stopWatching(mw.id)

pkg/watch/mux_test.go

@@ -30,7 +30,7 @@ type myType struct {
 
 func (*myType) IsAnAPIObject() {}
 
-func TestMux(t *testing.T) {
+func TestBroadcaster(t *testing.T) {
 	table := []Event{
 		{Added, &myType{"foo", "hello world 1"}},
 		{Added, &myType{"bar", "hello world 2"}},
@@ -38,8 +38,8 @@ func TestMux(t *testing.T) {
 		{Deleted, &myType{"bar", "hello world 4"}},
 	}
 
-	// The mux we're testing
-	m := NewMux(0)
+	// The broadcaster we're testing
+	m := NewBroadcaster(0)
 
 	// Add a bunch of watchers
 	const testWatchers = 2
@@ -76,8 +76,8 @@ func TestMux(t *testing.T) {
 	wg.Wait()
 }
 
-func TestMuxWatcherClose(t *testing.T) {
-	m := NewMux(0)
+func TestBroadcasterWatcherClose(t *testing.T) {
+	m := NewBroadcaster(0)
 	w := m.Watch()
 	w2 := m.Watch()
 	w.Stop()
@@ -93,11 +93,11 @@ func TestMuxWatcherClose(t *testing.T) {
 	w2.Stop()
 }
 
-func TestMuxWatcherStopDeadlock(t *testing.T) {
+func TestBroadcasterWatcherStopDeadlock(t *testing.T) {
 	done := make(chan bool)
-	m := NewMux(0)
+	m := NewBroadcaster(0)
 	go func(w0, w1 Interface) {
-		// We know Mux is in the distribute loop once one watcher receives
+		// We know Broadcaster is in the distribute loop once one watcher receives
 		// an event. Stop the other watcher while distribute is trying to
 		// send to it.
 		select {