feat: initial tracing support (#1623)

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()}
+}