Simplify RESTHander getter and remove specialized serializers

pkg/apiserver/apiserver.go

@@ -367,40 +367,42 @@ func SupportedResourcesHandler(s runtime.NegotiatedSerializer, groupVersion unve
 // 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, wsstream.NewDefaultReaderProtocols())
-			if err := r.Copy(w, req); err != nil {
-				utilruntime.HandleError(fmt.Errorf("error encountered while streaming results via websocket: %v", err))
-			}
-			return
-		}
+	stream, ok := object.(rest.ResourceStreamer)
+	if !ok {
+		writeNegotiated(s, gv, w, req, statusCode, object)
+		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)
+	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, wsstream.NewDefaultReaderProtocols())
+		if err := r.Copy(w, req); err != nil {
+			utilruntime.HandleError(fmt.Errorf("error encountered while streaming results via websocket: %v", err))
 		}
-		io.Copy(writer, out)
 		return
 	}
-	writeNegotiated(s, gv, w, req, statusCode, object)
+
+	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)
 }
 
 // writeNegotiated renders an object in the content type negotiated by the client

pkg/runtime/serializer/codec_factory.go

@@ -43,18 +43,12 @@ type serializerType struct {
 	// be expected to pass into or a gvk to Decode, since no type information will be available on
 	// the object itself.
 	RawSerializer runtime.Serializer
-	// Specialize gives the type the opportunity to return a different serializer implementation if
-	// the content type contains alternate operations. Here it is used to implement "pretty" as an
-	// option to application/json, but could also be used to allow serializers to perform type
-	// defaulting or alter output.
-	Specialize func(map[string]string) (runtime.Serializer, bool)
 
 	AcceptStreamContentTypes []string
 	StreamContentType        string
 
 	Framer           runtime.Framer
 	StreamSerializer runtime.Serializer
-	StreamSpecialize func(map[string]string) (runtime.Serializer, bool)
 }
 
 func newSerializersForScheme(scheme *runtime.Scheme, mf json.MetaFactory) []serializerType {
@@ -254,13 +248,6 @@ func (f CodecFactory) SerializerForMediaType(mediaType string, params map[string
 	for _, s := range f.serializers {
 		for _, accepted := range s.AcceptContentTypes {
 			if accepted == mediaType {
-				// specialization abstracts variants to the content type
-				if s.Specialize != nil && len(params) > 0 {
-					serializer, ok := s.Specialize(params)
-					// TODO: return formatted mediaType+params
-					return runtime.SerializerInfo{Serializer: serializer, MediaType: s.ContentType, EncodesAsText: s.EncodesAsText}, ok
-				}
-
 				// legacy support for ?pretty=1 continues, but this is more formally defined
 				if v, ok := params["pretty"]; ok && v == "1" && s.PrettySerializer != nil {
 					return runtime.SerializerInfo{Serializer: s.PrettySerializer, MediaType: s.ContentType, EncodesAsText: s.EncodesAsText}, true
@@ -286,20 +273,6 @@ func (f CodecFactory) StreamingSerializerForMediaType(mediaType string, params m
 					panic("no serializer defined for internal content type")
 				}
 
-				if s.StreamSpecialize != nil && len(params) > 0 {
-					serializer, ok := s.StreamSpecialize(params)
-					// TODO: return formatted mediaType+params
-					return runtime.StreamSerializerInfo{
-						SerializerInfo: runtime.SerializerInfo{
-							Serializer:    serializer,
-							MediaType:     s.StreamContentType,
-							EncodesAsText: s.EncodesAsText,
-						},
-						Framer:   s.Framer,
-						Embedded: nested,
-					}, ok
-				}
-
 				return runtime.StreamSerializerInfo{
 					SerializerInfo: runtime.SerializerInfo{
 						Serializer:    s.StreamSerializer,