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Diffstat (limited to 'vendor/github.com/grpc-ecosystem/grpc-gateway/v2/runtime/handler.go')
-rw-r--r--vendor/github.com/grpc-ecosystem/grpc-gateway/v2/runtime/handler.go223
1 files changed, 223 insertions, 0 deletions
diff --git a/vendor/github.com/grpc-ecosystem/grpc-gateway/v2/runtime/handler.go b/vendor/github.com/grpc-ecosystem/grpc-gateway/v2/runtime/handler.go
new file mode 100644
index 000000000..d1e21df48
--- /dev/null
+++ b/vendor/github.com/grpc-ecosystem/grpc-gateway/v2/runtime/handler.go
@@ -0,0 +1,223 @@
+package runtime
+
+import (
+ "context"
+ "fmt"
+ "io"
+ "net/http"
+ "net/textproto"
+ "strings"
+
+ "google.golang.org/genproto/googleapis/api/httpbody"
+ "google.golang.org/grpc/codes"
+ "google.golang.org/grpc/grpclog"
+ "google.golang.org/grpc/status"
+ "google.golang.org/protobuf/proto"
+)
+
+// ForwardResponseStream forwards the stream from gRPC server to REST client.
+func ForwardResponseStream(ctx context.Context, mux *ServeMux, marshaler Marshaler, w http.ResponseWriter, req *http.Request, recv func() (proto.Message, error), opts ...func(context.Context, http.ResponseWriter, proto.Message) error) {
+ f, ok := w.(http.Flusher)
+ if !ok {
+ grpclog.Infof("Flush not supported in %T", w)
+ http.Error(w, "unexpected type of web server", http.StatusInternalServerError)
+ return
+ }
+
+ md, ok := ServerMetadataFromContext(ctx)
+ if !ok {
+ grpclog.Infof("Failed to extract ServerMetadata from context")
+ http.Error(w, "unexpected error", http.StatusInternalServerError)
+ return
+ }
+ handleForwardResponseServerMetadata(w, mux, md)
+
+ w.Header().Set("Transfer-Encoding", "chunked")
+ if err := handleForwardResponseOptions(ctx, w, nil, opts); err != nil {
+ HTTPError(ctx, mux, marshaler, w, req, err)
+ return
+ }
+
+ var delimiter []byte
+ if d, ok := marshaler.(Delimited); ok {
+ delimiter = d.Delimiter()
+ } else {
+ delimiter = []byte("\n")
+ }
+
+ var wroteHeader bool
+ for {
+ resp, err := recv()
+ if err == io.EOF {
+ return
+ }
+ if err != nil {
+ handleForwardResponseStreamError(ctx, wroteHeader, marshaler, w, req, mux, err)
+ return
+ }
+ if err := handleForwardResponseOptions(ctx, w, resp, opts); err != nil {
+ handleForwardResponseStreamError(ctx, wroteHeader, marshaler, w, req, mux, err)
+ return
+ }
+
+ if !wroteHeader {
+ w.Header().Set("Content-Type", marshaler.ContentType(resp))
+ }
+
+ var buf []byte
+ httpBody, isHTTPBody := resp.(*httpbody.HttpBody)
+ switch {
+ case resp == nil:
+ buf, err = marshaler.Marshal(errorChunk(status.New(codes.Internal, "empty response")))
+ case isHTTPBody:
+ buf = httpBody.GetData()
+ default:
+ result := map[string]interface{}{"result": resp}
+ if rb, ok := resp.(responseBody); ok {
+ result["result"] = rb.XXX_ResponseBody()
+ }
+
+ buf, err = marshaler.Marshal(result)
+ }
+
+ if err != nil {
+ grpclog.Infof("Failed to marshal response chunk: %v", err)
+ handleForwardResponseStreamError(ctx, wroteHeader, marshaler, w, req, mux, err)
+ return
+ }
+ if _, err = w.Write(buf); err != nil {
+ grpclog.Infof("Failed to send response chunk: %v", err)
+ return
+ }
+ wroteHeader = true
+ if _, err = w.Write(delimiter); err != nil {
+ grpclog.Infof("Failed to send delimiter chunk: %v", err)
+ return
+ }
+ f.Flush()
+ }
+}
+
+func handleForwardResponseServerMetadata(w http.ResponseWriter, mux *ServeMux, md ServerMetadata) {
+ for k, vs := range md.HeaderMD {
+ if h, ok := mux.outgoingHeaderMatcher(k); ok {
+ for _, v := range vs {
+ w.Header().Add(h, v)
+ }
+ }
+ }
+}
+
+func handleForwardResponseTrailerHeader(w http.ResponseWriter, md ServerMetadata) {
+ for k := range md.TrailerMD {
+ tKey := textproto.CanonicalMIMEHeaderKey(fmt.Sprintf("%s%s", MetadataTrailerPrefix, k))
+ w.Header().Add("Trailer", tKey)
+ }
+}
+
+func handleForwardResponseTrailer(w http.ResponseWriter, md ServerMetadata) {
+ for k, vs := range md.TrailerMD {
+ tKey := fmt.Sprintf("%s%s", MetadataTrailerPrefix, k)
+ for _, v := range vs {
+ w.Header().Add(tKey, v)
+ }
+ }
+}
+
+// responseBody interface contains method for getting field for marshaling to the response body
+// this method is generated for response struct from the value of `response_body` in the `google.api.HttpRule`
+type responseBody interface {
+ XXX_ResponseBody() interface{}
+}
+
+// ForwardResponseMessage forwards the message "resp" from gRPC server to REST client.
+func ForwardResponseMessage(ctx context.Context, mux *ServeMux, marshaler Marshaler, w http.ResponseWriter, req *http.Request, resp proto.Message, opts ...func(context.Context, http.ResponseWriter, proto.Message) error) {
+ md, ok := ServerMetadataFromContext(ctx)
+ if !ok {
+ grpclog.Infof("Failed to extract ServerMetadata from context")
+ }
+
+ handleForwardResponseServerMetadata(w, mux, md)
+
+ // RFC 7230 https://tools.ietf.org/html/rfc7230#section-4.1.2
+ // Unless the request includes a TE header field indicating "trailers"
+ // is acceptable, as described in Section 4.3, a server SHOULD NOT
+ // generate trailer fields that it believes are necessary for the user
+ // agent to receive.
+ doForwardTrailers := requestAcceptsTrailers(req)
+
+ if doForwardTrailers {
+ handleForwardResponseTrailerHeader(w, md)
+ w.Header().Set("Transfer-Encoding", "chunked")
+ }
+
+ handleForwardResponseTrailerHeader(w, md)
+
+ contentType := marshaler.ContentType(resp)
+ w.Header().Set("Content-Type", contentType)
+
+ if err := handleForwardResponseOptions(ctx, w, resp, opts); err != nil {
+ HTTPError(ctx, mux, marshaler, w, req, err)
+ return
+ }
+ var buf []byte
+ var err error
+ if rb, ok := resp.(responseBody); ok {
+ buf, err = marshaler.Marshal(rb.XXX_ResponseBody())
+ } else {
+ buf, err = marshaler.Marshal(resp)
+ }
+ if err != nil {
+ grpclog.Infof("Marshal error: %v", err)
+ HTTPError(ctx, mux, marshaler, w, req, err)
+ return
+ }
+
+ if _, err = w.Write(buf); err != nil {
+ grpclog.Infof("Failed to write response: %v", err)
+ }
+
+ if doForwardTrailers {
+ handleForwardResponseTrailer(w, md)
+ }
+}
+
+func requestAcceptsTrailers(req *http.Request) bool {
+ te := req.Header.Get("TE")
+ return strings.Contains(strings.ToLower(te), "trailers")
+}
+
+func handleForwardResponseOptions(ctx context.Context, w http.ResponseWriter, resp proto.Message, opts []func(context.Context, http.ResponseWriter, proto.Message) error) error {
+ if len(opts) == 0 {
+ return nil
+ }
+ for _, opt := range opts {
+ if err := opt(ctx, w, resp); err != nil {
+ grpclog.Infof("Error handling ForwardResponseOptions: %v", err)
+ return err
+ }
+ }
+ return nil
+}
+
+func handleForwardResponseStreamError(ctx context.Context, wroteHeader bool, marshaler Marshaler, w http.ResponseWriter, req *http.Request, mux *ServeMux, err error) {
+ st := mux.streamErrorHandler(ctx, err)
+ msg := errorChunk(st)
+ if !wroteHeader {
+ w.Header().Set("Content-Type", marshaler.ContentType(msg))
+ w.WriteHeader(HTTPStatusFromCode(st.Code()))
+ }
+ buf, merr := marshaler.Marshal(msg)
+ if merr != nil {
+ grpclog.Infof("Failed to marshal an error: %v", merr)
+ return
+ }
+ if _, werr := w.Write(buf); werr != nil {
+ grpclog.Infof("Failed to notify error to client: %v", werr)
+ return
+ }
+}
+
+func errorChunk(st *status.Status) map[string]proto.Message {
+ return map[string]proto.Message{"error": st.Proto()}
+}