func createStreams(req *http.Request, w http.ResponseWriter, supportedStreamProtocols []string, idleTimeout, streamCreationTimeout time.Duration) (*context, bool) {
	opts, err := newOptions(req)
	if err != nil {
		runtime.HandleError(err)
		w.WriteHeader(http.StatusBadRequest)
		fmt.Fprint(w, err.Error())
		return nil, false
	}

	if wsstream.IsWebSocketRequest(req) {
		return createWebSocketStreams(req, w, opts, idleTimeout)
	}

	protocol, err := httpstream.Handshake(req, w, supportedStreamProtocols)
	if err != nil {
		w.WriteHeader(http.StatusBadRequest)
		fmt.Fprint(w, err.Error())
		return nil, false
	}

	streamCh := make(chan streamAndReply)

	upgrader := spdy.NewResponseUpgrader()
	conn := upgrader.UpgradeResponse(w, req, func(stream httpstream.Stream, replySent <-chan struct{}) error {
		streamCh <- streamAndReply{Stream: stream, replySent: replySent}
		return nil
	})
	// from this point on, we can no longer call methods on response
	if conn == nil {
		// The upgrader is responsible for notifying the client of any errors that
		// occurred during upgrading. All we can do is return here at this point
		// if we weren't successful in upgrading.
		return nil, false
	}

	conn.SetIdleTimeout(idleTimeout)

	var handler protocolHandler
	switch protocol {
	case StreamProtocolV2Name:
		handler = &v2ProtocolHandler{}
	case "":
		glog.V(4).Infof("Client did not request protocol negotiaion. Falling back to %q", StreamProtocolV1Name)
		fallthrough
	case StreamProtocolV1Name:
		handler = &v1ProtocolHandler{}
	}

	expired := time.NewTimer(streamCreationTimeout)

	ctx, err := handler.waitForStreams(streamCh, opts.expectedStreams, expired.C)
	if err != nil {
		runtime.HandleError(err)
		return nil, false
	}

	ctx.conn = conn
	ctx.tty = opts.tty
	return ctx, true
}
// write renders a returned runtime.Object to the response as a stream or an encoded object. If the object
// returned by the response implements rest.ResourceStreamer that interface will be used to render the
// response. The Accept header and current API version will be passed in, and the output will be copied
// directly to the response body. If content type is returned it is used, otherwise the content type will
// be "application/octet-stream". All other objects are sent to standard JSON serialization.
func write(statusCode int, gv unversioned.GroupVersion, s runtime.NegotiatedSerializer, object runtime.Object, w http.ResponseWriter, req *http.Request) {
	if stream, ok := object.(rest.ResourceStreamer); ok {
		out, flush, contentType, err := stream.InputStream(gv.String(), req.Header.Get("Accept"))
		if err != nil {
			errorNegotiated(err, s, gv, w, req)
			return
		}
		if out == nil {
			// No output provided - return StatusNoContent
			w.WriteHeader(http.StatusNoContent)
			return
		}
		defer out.Close()

		if wsstream.IsWebSocketRequest(req) {
			r := wsstream.NewReader(out, true)
			if err := r.Copy(w, req); err != nil {
				utilruntime.HandleError(fmt.Errorf("error encountered while streaming results via websocket: %v", err))
			}
			return
		}

		if len(contentType) == 0 {
			contentType = "application/octet-stream"
		}
		w.Header().Set("Content-Type", contentType)
		w.WriteHeader(statusCode)
		writer := w.(io.Writer)
		if flush {
			writer = flushwriter.Wrap(w)
		}
		io.Copy(writer, out)
		return
	}
	writeNegotiated(s, gv, w, req, statusCode, object)
}
Exemple #3
0
// Serve serves a series of encoded events via HTTP with Transfer-Encoding: chunked
// or over a websocket connection.
func (s *WatchServer) ServeHTTP(w http.ResponseWriter, req *http.Request) {
	w = httplog.Unlogged(w)

	if wsstream.IsWebSocketRequest(req) {
		w.Header().Set("Content-Type", s.mediaType)
		websocket.Handler(s.HandleWS).ServeHTTP(w, req)
		return
	}

	cn, ok := w.(http.CloseNotifier)
	if !ok {
		err := fmt.Errorf("unable to start watch - can't get http.CloseNotifier: %#v", w)
		utilruntime.HandleError(err)
		s.scope.err(errors.NewInternalError(err), w, req)
		return
	}
	flusher, ok := w.(http.Flusher)
	if !ok {
		err := fmt.Errorf("unable to start watch - can't get http.Flusher: %#v", w)
		utilruntime.HandleError(err)
		s.scope.err(errors.NewInternalError(err), w, req)
		return
	}

	framer := s.framer.NewFrameWriter(w)
	if framer == nil {
		// programmer error
		err := fmt.Errorf("no stream framing support is available for media type %q", s.mediaType)
		utilruntime.HandleError(err)
		s.scope.err(errors.NewBadRequest(err.Error()), w, req)
		return
	}
	e := streaming.NewEncoder(framer, s.encoder)

	// ensure the connection times out
	timeoutCh, cleanup := s.t.TimeoutCh()
	defer cleanup()
	defer s.watching.Stop()

	// begin the stream
	w.Header().Set("Content-Type", s.mediaType)
	w.Header().Set("Transfer-Encoding", "chunked")
	w.WriteHeader(http.StatusOK)
	flusher.Flush()

	var unknown runtime.Unknown
	internalEvent := &versioned.InternalEvent{}
	buf := &bytes.Buffer{}
	ch := s.watching.ResultChan()
	for {
		select {
		case <-cn.CloseNotify():
			return
		case <-timeoutCh:
			return
		case event, ok := <-ch:
			if !ok {
				// End of results.
				return
			}

			obj := event.Object
			s.fixup(obj)
			if err := s.embeddedEncoder.Encode(obj, buf); err != nil {
				// unexpected error
				utilruntime.HandleError(fmt.Errorf("unable to encode watch object: %v", err))
				return
			}

			// ContentType is not required here because we are defaulting to the serializer
			// type
			unknown.Raw = buf.Bytes()
			event.Object = &unknown

			// the internal event will be versioned by the encoder
			*internalEvent = versioned.InternalEvent(event)
			if err := e.Encode(internalEvent); err != nil {
				utilruntime.HandleError(fmt.Errorf("unable to encode watch object: %v (%#v)", err, e))
				// client disconnect.
				return
			}
			if len(ch) == 0 {
				flusher.Flush()
			}

			buf.Reset()
		}
	}
}