Import of https://github.com/ciena/voltctl at commit 40d61fbf3f910ed4017cf67c9c79e8e1f82a33a5
Change-Id: I8464c59e60d76cb8612891db3303878975b5416c
diff --git a/vendor/k8s.io/apimachinery/pkg/watch/streamwatcher.go b/vendor/k8s.io/apimachinery/pkg/watch/streamwatcher.go
new file mode 100644
index 0000000..93bb1cd
--- /dev/null
+++ b/vendor/k8s.io/apimachinery/pkg/watch/streamwatcher.go
@@ -0,0 +1,119 @@
+/*
+Copyright 2014 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+ http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package watch
+
+import (
+ "io"
+ "sync"
+
+ "github.com/golang/glog"
+ "k8s.io/apimachinery/pkg/runtime"
+ "k8s.io/apimachinery/pkg/util/net"
+ utilruntime "k8s.io/apimachinery/pkg/util/runtime"
+)
+
+// Decoder allows StreamWatcher to watch any stream for which a Decoder can be written.
+type Decoder interface {
+ // Decode should return the type of event, the decoded object, or an error.
+ // An error will cause StreamWatcher to call Close(). Decode should block until
+ // it has data or an error occurs.
+ Decode() (action EventType, object runtime.Object, err error)
+
+ // Close should close the underlying io.Reader, signalling to the source of
+ // the stream that it is no longer being watched. Close() must cause any
+ // outstanding call to Decode() to return with an error of some sort.
+ Close()
+}
+
+// StreamWatcher turns any stream for which you can write a Decoder interface
+// into a watch.Interface.
+type StreamWatcher struct {
+ sync.Mutex
+ source Decoder
+ result chan Event
+ stopped bool
+}
+
+// NewStreamWatcher creates a StreamWatcher from the given decoder.
+func NewStreamWatcher(d Decoder) *StreamWatcher {
+ sw := &StreamWatcher{
+ source: d,
+ // It's easy for a consumer to add buffering via an extra
+ // goroutine/channel, but impossible for them to remove it,
+ // so nonbuffered is better.
+ result: make(chan Event),
+ }
+ go sw.receive()
+ return sw
+}
+
+// ResultChan implements Interface.
+func (sw *StreamWatcher) ResultChan() <-chan Event {
+ return sw.result
+}
+
+// Stop implements Interface.
+func (sw *StreamWatcher) Stop() {
+ // Call Close() exactly once by locking and setting a flag.
+ sw.Lock()
+ defer sw.Unlock()
+ if !sw.stopped {
+ sw.stopped = true
+ sw.source.Close()
+ }
+}
+
+// stopping returns true if Stop() was called previously.
+func (sw *StreamWatcher) stopping() bool {
+ sw.Lock()
+ defer sw.Unlock()
+ return sw.stopped
+}
+
+// receive reads result from the decoder in a loop and sends down the result channel.
+func (sw *StreamWatcher) receive() {
+ defer close(sw.result)
+ defer sw.Stop()
+ defer utilruntime.HandleCrash()
+ for {
+ action, obj, err := sw.source.Decode()
+ if err != nil {
+ // Ignore expected error.
+ if sw.stopping() {
+ return
+ }
+ switch err {
+ case io.EOF:
+ // watch closed normally
+ case io.ErrUnexpectedEOF:
+ glog.V(1).Infof("Unexpected EOF during watch stream event decoding: %v", err)
+ default:
+ msg := "Unable to decode an event from the watch stream: %v"
+ if net.IsProbableEOF(err) {
+ glog.V(5).Infof(msg, err)
+ } else {
+ glog.Errorf(msg, err)
+ }
+ }
+ return
+ }
+ sw.result <- Event{
+ Type: action,
+ Object: obj,
+ }
+ }
+}