// 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,
}
}
}
// Watch attempts to begin watching the requested location.
// Returns a watch.Interface, or an error.
func (r *Request) Watch() (watch.Interface, error) {
// We specifically don't want to rate limit watches, so we
// don't use r.throttle here.
if r.err != nil {
return nil, r.err
}
if r.serializers.Framer == nil {
return nil, fmt.Errorf("watching resources is not possible with this client (content-type: %s)", r.content.ContentType)
}
url := r.URL().String()
req, err := http.NewRequest(r.verb, url, r.body)
if err != nil {
return nil, err
}
if r.ctx != nil {
req = req.WithContext(r.ctx)
}
req.Header = r.headers
client := r.client
if client == nil {
client = http.DefaultClient
}
r.backoffMgr.Sleep(r.backoffMgr.CalculateBackoff(r.URL()))
resp, err := client.Do(req)
updateURLMetrics(r, resp, err)
if r.baseURL != nil {
if err != nil {
r.backoffMgr.UpdateBackoff(r.baseURL, err, 0)
} else {
r.backoffMgr.UpdateBackoff(r.baseURL, err, resp.StatusCode)
}
}
if err != nil {
// The watch stream mechanism handles many common partial data errors, so closed
// connections can be retried in many cases.
if net.IsProbableEOF(err) {
return watch.NewEmptyWatch(), nil
}
return nil, err
}
if resp.StatusCode != http.StatusOK {
defer resp.Body.Close()
if result := r.transformResponse(resp, req); result.err != nil {
return nil, result.err
}
return nil, fmt.Errorf("for request '%+v', got status: %v", url, resp.StatusCode)
}
framer := r.serializers.Framer.NewFrameReader(resp.Body)
decoder := streaming.NewDecoder(framer, r.serializers.StreamingSerializer)
return watch.NewStreamWatcher(restclientwatch.NewDecoder(decoder, r.serializers.Decoder)), nil
}