vendor dependencies

vendor/k8s.io/apiserver/pkg/endpoints/handlers/responsewriters/writers.go

@@ -35,6 +35,26 @@ import (
 	"k8s.io/apiserver/pkg/util/wsstream"
 )
 
+// httpResponseWriterWithInit wraps http.ResponseWriter, and implements the io.Writer interface to be used
+// with encoding. The purpose is to allow for encoding to a stream, while accommodating a custom HTTP status code
+// if encoding fails, and meeting the encoder's io.Writer interface requirement.
+type httpResponseWriterWithInit struct {
+	hasWritten bool
+	mediaType  string
+	statusCode int
+	innerW     http.ResponseWriter
+}
+
+func (w httpResponseWriterWithInit) Write(b []byte) (n int, err error) {
+	if !w.hasWritten {
+		w.innerW.Header().Set("Content-Type", w.mediaType)
+		w.innerW.WriteHeader(w.statusCode)
+		w.hasWritten = true
+	}
+
+	return w.innerW.Write(b)
+}
+
 // WriteObject 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
@@ -44,7 +64,7 @@ func WriteObject(statusCode int, gv schema.GroupVersion, s runtime.NegotiatedSer
 	stream, ok := object.(rest.ResourceStreamer)
 	if ok {
 		requestInfo, _ := request.RequestInfoFrom(req.Context())
-		metrics.RecordLongRunning(req, requestInfo, func() {
+		metrics.RecordLongRunning(req, requestInfo, metrics.APIServerComponent, func() {
 			StreamObject(statusCode, gv, s, stream, w, req)
 		})
 		return
@@ -56,7 +76,7 @@ func WriteObject(statusCode int, gv schema.GroupVersion, s runtime.NegotiatedSer
 // If the client requests a websocket upgrade, negotiate for a websocket reader protocol (because many
 // browser clients cannot easily handle binary streaming protocols).
 func StreamObject(statusCode int, gv schema.GroupVersion, s runtime.NegotiatedSerializer, stream rest.ResourceStreamer, w http.ResponseWriter, req *http.Request) {
-	out, flush, contentType, err := stream.InputStream(gv.String(), req.Header.Get("Accept"))
+	out, flush, contentType, err := stream.InputStream(req.Context(), gv.String(), req.Header.Get("Accept"))
 	if err != nil {
 		ErrorNegotiated(err, s, gv, w, req)
 		return
@@ -81,6 +101,10 @@ func StreamObject(statusCode int, gv schema.GroupVersion, s runtime.NegotiatedSe
 	}
 	w.Header().Set("Content-Type", contentType)
 	w.WriteHeader(statusCode)
+	// Flush headers, if possible
+	if flusher, ok := w.(http.Flusher); ok {
+		flusher.Flush()
+	}
 	writer := w.(io.Writer)
 	if flush {
 		writer = flushwriter.Wrap(w)
@@ -90,12 +114,11 @@ func StreamObject(statusCode int, gv schema.GroupVersion, s runtime.NegotiatedSe
 
 // SerializeObject renders an object in the content type negotiated by the client using the provided encoder.
 // The context is optional and can be nil.
-func SerializeObject(mediaType string, encoder runtime.Encoder, w http.ResponseWriter, req *http.Request, statusCode int, object runtime.Object) {
-	w.Header().Set("Content-Type", mediaType)
-	w.WriteHeader(statusCode)
+func SerializeObject(mediaType string, encoder runtime.Encoder, innerW http.ResponseWriter, req *http.Request, statusCode int, object runtime.Object) {
+	w := httpResponseWriterWithInit{mediaType: mediaType, innerW: innerW, statusCode: statusCode}
 
 	if err := encoder.Encode(object, w); err != nil {
-		errorJSONFatal(err, encoder, w)
+		errSerializationFatal(err, encoder, w)
 	}
 }
 
@@ -143,22 +166,23 @@ func ErrorNegotiated(err error, s runtime.NegotiatedSerializer, gv schema.GroupV
 	return code
 }
 
-// errorJSONFatal renders an error to the response, and if codec fails will render plaintext.
+// errSerializationFatal renders an error to the response, and if codec fails will render plaintext.
 // Returns the HTTP status code of the error.
-func errorJSONFatal(err error, codec runtime.Encoder, w http.ResponseWriter) int {
+func errSerializationFatal(err error, codec runtime.Encoder, w httpResponseWriterWithInit) {
 	utilruntime.HandleError(fmt.Errorf("apiserver was unable to write a JSON response: %v", err))
 	status := ErrorToAPIStatus(err)
-	code := int(status.Code)
+	candidateStatusCode := int(status.Code)
+	// If original statusCode was not successful, we need to return the original error.
+	// We cannot hide it behind serialization problems
+	if w.statusCode >= http.StatusOK && w.statusCode < http.StatusBadRequest {
+		w.statusCode = candidateStatusCode
+	}
 	output, err := runtime.Encode(codec, status)
 	if err != nil {
-		w.WriteHeader(code)
-		fmt.Fprintf(w, "%s: %s", status.Reason, status.Message)
-		return code
+		w.mediaType = "text/plain"
+		output = []byte(fmt.Sprintf("%s: %s", status.Reason, status.Message))
 	}
-	w.Header().Set("Content-Type", "application/json")
-	w.WriteHeader(code)
 	w.Write(output)
-	return code
 }
 
 // WriteRawJSON writes a non-API object in JSON.