Merge pull request improbable-eng#166 from improbable-eng/feature/fix…

…-exports

Change visibility of new GRPC WebSocket functions.

go/grpcweb/DOC.md

@@ -124,86 +124,6 @@ bidirectional requests.
 
 The default behaviour is false, i.e. to disallow websockets
 
-#### type WebSocketResponseWriter
-
-```go
-type WebSocketResponseWriter struct {
-}
-```
-
-
-#### func (*WebSocketResponseWriter) CloseNotify
-
-```go
-func (w *WebSocketResponseWriter) CloseNotify() <-chan bool
-```
-
-#### func (*WebSocketResponseWriter) Flush
-
-```go
-func (w *WebSocketResponseWriter) Flush()
-```
-
-#### func (*WebSocketResponseWriter) FlushTrailers
-
-```go
-func (w *WebSocketResponseWriter) FlushTrailers()
-```
-
-#### func (*WebSocketResponseWriter) Header
-
-```go
-func (w *WebSocketResponseWriter) Header() http.Header
-```
-
-#### func (*WebSocketResponseWriter) Write
-
-```go
-func (w *WebSocketResponseWriter) Write(b []byte) (int, error)
-```
-
-#### func (*WebSocketResponseWriter) WriteHeader
-
-```go
-func (w *WebSocketResponseWriter) WriteHeader(code int)
-```
-
-#### type WebSocketWrappedReader
-
-```go
-type WebSocketWrappedReader struct {
-}
-```
-
-
-#### func  NewWebsocketWrappedReader
-
-```go
-func NewWebsocketWrappedReader(wsConn *websocket.Conn, respWriter *WebSocketResponseWriter) *WebSocketWrappedReader
-```
-
-#### func (*WebSocketWrappedReader) Close
-
-```go
-func (w *WebSocketWrappedReader) Close() error
-```
-
-#### func (*WebSocketWrappedReader) Read
-
-```go
-func (w *WebSocketWrappedReader) Read(p []byte) (int, error)
-```
-First byte of a binary WebSocket frame is used for control flow: 0 = Data 1 =
-End of client send
-
-#### type WebSocketWrapper
-
-```go
-type WebSocketWrapper struct {
-}
-```
-
-
 #### type WrappedGrpcServer
 
 ```go
@@ -242,6 +162,10 @@ with the gRPC-Web protocol.
 ```go
 func (w *WrappedGrpcServer) HandleGrpcWebsocketRequest(resp http.ResponseWriter, req *http.Request)
 ```
+HandleGrpcWebsocketRequest takes a HTTP request that is assumed to be a
+gRPC-Websocket request and wraps it with a compatibility layer to transform it
+to a standard gRPC request for the wrapped gRPC server and transforms the
+response to comply with the gRPC-Web protocol.
 
 #### func (*WrappedGrpcServer) IsAcceptableGrpcCorsRequest
 
@@ -267,6 +191,8 @@ the "content-type" is "application/grpc-web" and that the method is POST.
 ```go
 func (w *WrappedGrpcServer) IsGrpcWebSocketRequest(req *http.Request) bool
 ```
+IsGrpcWebSocketRequest determines if a request is a gRPC-Web request by checking
+that the "Sec-Websocket-Protocol" header value is "grpc-websockets"
 
 #### func (*WrappedGrpcServer) ServeHTTP
 

go/grpcweb/websocket_wrapper.go

@@ -14,20 +14,16 @@ import (
 	"golang.org/x/net/http2"
 )
 
-type WebSocketWrapper struct {
-	wsConn *websocket.Conn
-}
-
-type WebSocketResponseWriter struct {
+type webSocketResponseWriter struct {
 	writtenHeaders  bool
 	wsConn          *websocket.Conn
 	headers         http.Header
 	flushedHeaders  http.Header
 	closeNotifyChan chan bool
 }
 
-func newWebSocketResponseWriter(wsConn *websocket.Conn) *WebSocketResponseWriter {
-	return &WebSocketResponseWriter{
+func newWebSocketResponseWriter(wsConn *websocket.Conn) *webSocketResponseWriter {
+	return &webSocketResponseWriter{
 		writtenHeaders:  false,
 		headers:         make(http.Header),
 		flushedHeaders:  make(http.Header),
@@ -36,18 +32,18 @@ func newWebSocketResponseWriter(wsConn *websocket.Conn) *WebSocketResponseWriter
 	}
 }
 
-func (w *WebSocketResponseWriter) Header() http.Header {
+func (w *webSocketResponseWriter) Header() http.Header {
 	return w.headers
 }
 
-func (w *WebSocketResponseWriter) Write(b []byte) (int, error) {
+func (w *webSocketResponseWriter) Write(b []byte) (int, error) {
 	if !w.writtenHeaders {
 		w.WriteHeader(http.StatusOK)
 	}
 	return len(b), w.wsConn.WriteMessage(websocket.BinaryMessage, b)
 }
 
-func (w *WebSocketResponseWriter) writeHeaderFrame(headers http.Header) {
+func (w *webSocketResponseWriter) writeHeaderFrame(headers http.Header) {
 	headerBuffer := new(bytes.Buffer)
 	headers.Write(headerBuffer)
 	headerGrpcDataHeader := []byte{1 << 7, 0, 0, 0, 0} // MSB=1 indicates this is a header data frame.
@@ -56,7 +52,7 @@ func (w *WebSocketResponseWriter) writeHeaderFrame(headers http.Header) {
 	w.wsConn.WriteMessage(websocket.BinaryMessage, headerBuffer.Bytes())
 }
 
-func (w *WebSocketResponseWriter) copyFlushedHeaders() {
+func (w *webSocketResponseWriter) copyFlushedHeaders() {
 	for k, vv := range w.headers {
 		// Skip the pre-annoucement of Trailer headers. Don't add them to the response headers.
 		if strings.ToLower(k) == "trailer" {
@@ -68,14 +64,14 @@ func (w *WebSocketResponseWriter) copyFlushedHeaders() {
 	}
 }
 
-func (w *WebSocketResponseWriter) WriteHeader(code int) {
+func (w *webSocketResponseWriter) WriteHeader(code int) {
 	w.copyFlushedHeaders()
 	w.writtenHeaders = true
 	w.writeHeaderFrame(w.headers)
 	return
 }
 
-func (w *WebSocketResponseWriter) extractTrailerHeaders() http.Header {
+func (w *webSocketResponseWriter) extractTrailerHeaders() http.Header {
 	trailerHeaders := make(http.Header)
 	for k, vv := range w.headers {
 		// Skip the pre-annoucement of Trailer headers. Don't add them to the response headers.
@@ -97,34 +93,34 @@ func (w *WebSocketResponseWriter) extractTrailerHeaders() http.Header {
 	return trailerHeaders
 }
 
-func (w *WebSocketResponseWriter) FlushTrailers() {
+func (w *webSocketResponseWriter) FlushTrailers() {
 	w.writeHeaderFrame(w.extractTrailerHeaders())
 }
 
-func (w *WebSocketResponseWriter) Flush() {
+func (w *webSocketResponseWriter) Flush() {
 	// no-op
 }
 
-func (w *WebSocketResponseWriter) CloseNotify() <-chan bool {
+func (w *webSocketResponseWriter) CloseNotify() <-chan bool {
 	return w.closeNotifyChan
 }
 
-type WebSocketWrappedReader struct {
+type webSocketWrappedReader struct {
 	wsConn          *websocket.Conn
-	respWriter      *WebSocketResponseWriter
+	respWriter      *webSocketResponseWriter
 	remainingBuffer []byte
 	remainingError  error
 }
 
-func (w *WebSocketWrappedReader) Close() error {
+func (w *webSocketWrappedReader) Close() error {
 	w.respWriter.FlushTrailers()
 	return w.wsConn.Close()
 }
 
 // First byte of a binary WebSocket frame is used for control flow:
 // 0 = Data
 // 1 = End of client send
-func (w *WebSocketWrappedReader) Read(p []byte) (int, error) {
+func (w *webSocketWrappedReader) Read(p []byte) (int, error) {
 	// If a buffer remains from a previous WebSocket frame read then continue reading it
 	if w.remainingBuffer != nil {
 
@@ -197,8 +193,8 @@ func (w *WebSocketWrappedReader) Read(p []byte) (int, error) {
 	return len(p), nil
 }
 
-func NewWebsocketWrappedReader(wsConn *websocket.Conn, respWriter *WebSocketResponseWriter) *WebSocketWrappedReader {
-	return &WebSocketWrappedReader{
+func newWebsocketWrappedReader(wsConn *websocket.Conn, respWriter *webSocketResponseWriter) *webSocketWrappedReader {
+	return &webSocketWrappedReader{
 		wsConn:          wsConn,
 		respWriter:      respWriter,
 		remainingBuffer: nil,

go/grpcweb/wrapper.go

@@ -95,6 +95,8 @@ func (w *WrappedGrpcServer) ServeHTTP(resp http.ResponseWriter, req *http.Reques
 	w.server.ServeHTTP(resp, req)
 }
 
+// IsGrpcWebSocketRequest determines if a request is a gRPC-Web request by checking that the "Sec-Websocket-Protocol"
+// header value is "grpc-websockets"
 func (w *WrappedGrpcServer) IsGrpcWebSocketRequest(req *http.Request) bool {
 	return req.Header.Get("Upgrade") == "websocket" && req.Header.Get("Sec-Websocket-Protocol") == "grpc-websockets"
 }
@@ -116,13 +118,15 @@ var websocketUpgrader = websocket.Upgrader{
 	Subprotocols:    []string{"grpc-websockets"},
 }
 
+// HandleGrpcWebsocketRequest takes a HTTP request that is assumed to be a gRPC-Websocket request and wraps it with a
+// compatibility layer to transform it to a standard gRPC request for the wrapped gRPC server and transforms the
+// response to comply with the gRPC-Web protocol.
 func (w *WrappedGrpcServer) HandleGrpcWebsocketRequest(resp http.ResponseWriter, req *http.Request) {
 	conn, err := websocketUpgrader.Upgrade(resp, req, nil)
 	if err != nil {
 		grpclog.Errorf("Unable to upgrade websocket request: %v", err)
 		return
 	}
-
 	w.handleWebSocket(conn, req)
 }
 
@@ -145,7 +149,7 @@ func (w *WrappedGrpcServer) handleWebSocket(wsConn *websocket.Conn, req *http.Re
 	}
 
 	respWriter := newWebSocketResponseWriter(wsConn)
-	wrappedReader := NewWebsocketWrappedReader(wsConn, respWriter)
+	wrappedReader := newWebsocketWrappedReader(wsConn, respWriter)
 
 	req.Body = wrappedReader
 	req.Method = http.MethodPost