[otel-tracing] vendor and go modules changes

This tracks all the vendor file changes and changes to go modules due
to OpenTelemetry support

Signed-off-by: Alakesh Haloi <alakeshh@amazon.com>

vendor/github.com/grpc-ecosystem/grpc-gateway/runtime/errors.go

@@ -0,0 +1,186 @@
+package runtime
+
+import (
+	"context"
+	"io"
+	"net/http"
+	"strings"
+
+	"github.com/grpc-ecosystem/grpc-gateway/internal"
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/grpclog"
+	"google.golang.org/grpc/status"
+)
+
+// HTTPStatusFromCode converts a gRPC error code into the corresponding HTTP response status.
+// See: https://github.com/googleapis/googleapis/blob/master/google/rpc/code.proto
+func HTTPStatusFromCode(code codes.Code) int {
+	switch code {
+	case codes.OK:
+		return http.StatusOK
+	case codes.Canceled:
+		return http.StatusRequestTimeout
+	case codes.Unknown:
+		return http.StatusInternalServerError
+	case codes.InvalidArgument:
+		return http.StatusBadRequest
+	case codes.DeadlineExceeded:
+		return http.StatusGatewayTimeout
+	case codes.NotFound:
+		return http.StatusNotFound
+	case codes.AlreadyExists:
+		return http.StatusConflict
+	case codes.PermissionDenied:
+		return http.StatusForbidden
+	case codes.Unauthenticated:
+		return http.StatusUnauthorized
+	case codes.ResourceExhausted:
+		return http.StatusTooManyRequests
+	case codes.FailedPrecondition:
+		// Note, this deliberately doesn't translate to the similarly named '412 Precondition Failed' HTTP response status.
+		return http.StatusBadRequest
+	case codes.Aborted:
+		return http.StatusConflict
+	case codes.OutOfRange:
+		return http.StatusBadRequest
+	case codes.Unimplemented:
+		return http.StatusNotImplemented
+	case codes.Internal:
+		return http.StatusInternalServerError
+	case codes.Unavailable:
+		return http.StatusServiceUnavailable
+	case codes.DataLoss:
+		return http.StatusInternalServerError
+	}
+
+	grpclog.Infof("Unknown gRPC error code: %v", code)
+	return http.StatusInternalServerError
+}
+
+var (
+	// HTTPError replies to the request with an error.
+	//
+	// HTTPError is called:
+	//  - From generated per-endpoint gateway handler code, when calling the backend results in an error.
+	//  - From gateway runtime code, when forwarding the response message results in an error.
+	//
+	// The default value for HTTPError calls the custom error handler configured on the ServeMux via the
+	// WithProtoErrorHandler serve option if that option was used, calling GlobalHTTPErrorHandler otherwise.
+	//
+	// To customize the error handling of a particular ServeMux instance, use the WithProtoErrorHandler
+	// serve option.
+	//
+	// To customize the error format for all ServeMux instances not using the WithProtoErrorHandler serve
+	// option, set GlobalHTTPErrorHandler to a custom function.
+	//
+	// Setting this variable directly to customize error format is deprecated.
+	HTTPError = MuxOrGlobalHTTPError
+
+	// GlobalHTTPErrorHandler is the HTTPError handler for all ServeMux instances not using the
+	// WithProtoErrorHandler serve option.
+	//
+	// You can set a custom function to this variable to customize error format.
+	GlobalHTTPErrorHandler = DefaultHTTPError
+
+	// OtherErrorHandler handles gateway errors from parsing and routing client requests for all
+	// ServeMux instances not using the WithProtoErrorHandler serve option.
+	//
+	// It returns the following error codes: StatusMethodNotAllowed StatusNotFound StatusBadRequest
+	//
+	// To customize parsing and routing error handling of a particular ServeMux instance, use the
+	// WithProtoErrorHandler serve option.
+	//
+	// To customize parsing and routing error handling of all ServeMux instances not using the
+	// WithProtoErrorHandler serve option, set a custom function to this variable.
+	OtherErrorHandler = DefaultOtherErrorHandler
+)
+
+// MuxOrGlobalHTTPError uses the mux-configured error handler, falling back to GlobalErrorHandler.
+func MuxOrGlobalHTTPError(ctx context.Context, mux *ServeMux, marshaler Marshaler, w http.ResponseWriter, r *http.Request, err error) {
+	if mux.protoErrorHandler != nil {
+		mux.protoErrorHandler(ctx, mux, marshaler, w, r, err)
+	} else {
+		GlobalHTTPErrorHandler(ctx, mux, marshaler, w, r, err)
+	}
+}
+
+// DefaultHTTPError is the default implementation of HTTPError.
+// If "err" is an error from gRPC system, the function replies with the status code mapped by HTTPStatusFromCode.
+// If otherwise, it replies with http.StatusInternalServerError.
+//
+// The response body returned by this function is a JSON object,
+// which contains a member whose key is "error" and whose value is err.Error().
+func DefaultHTTPError(ctx context.Context, mux *ServeMux, marshaler Marshaler, w http.ResponseWriter, r *http.Request, err error) {
+	const fallback = `{"error": "failed to marshal error message"}`
+
+	s, ok := status.FromError(err)
+	if !ok {
+		s = status.New(codes.Unknown, err.Error())
+	}
+
+	w.Header().Del("Trailer")
+	w.Header().Del("Transfer-Encoding")
+
+	contentType := marshaler.ContentType()
+	// Check marshaler on run time in order to keep backwards compatibility
+	// An interface param needs to be added to the ContentType() function on
+	// the Marshal interface to be able to remove this check
+	if typeMarshaler, ok := marshaler.(contentTypeMarshaler); ok {
+		pb := s.Proto()
+		contentType = typeMarshaler.ContentTypeFromMessage(pb)
+	}
+	w.Header().Set("Content-Type", contentType)
+
+	body := &internal.Error{
+		Error:   s.Message(),
+		Message: s.Message(),
+		Code:    int32(s.Code()),
+		Details: s.Proto().GetDetails(),
+	}
+
+	buf, merr := marshaler.Marshal(body)
+	if merr != nil {
+		grpclog.Infof("Failed to marshal error message %q: %v", body, merr)
+		w.WriteHeader(http.StatusInternalServerError)
+		if _, err := io.WriteString(w, fallback); err != nil {
+			grpclog.Infof("Failed to write response: %v", err)
+		}
+		return
+	}
+
+	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.
+	var wantsTrailers bool
+
+	if te := r.Header.Get("TE"); strings.Contains(strings.ToLower(te), "trailers") {
+		wantsTrailers = true
+		handleForwardResponseTrailerHeader(w, md)
+		w.Header().Set("Transfer-Encoding", "chunked")
+	}
+
+	st := HTTPStatusFromCode(s.Code())
+	w.WriteHeader(st)
+	if _, err := w.Write(buf); err != nil {
+		grpclog.Infof("Failed to write response: %v", err)
+	}
+
+	if wantsTrailers {
+		handleForwardResponseTrailer(w, md)
+	}
+}
+
+// DefaultOtherErrorHandler is the default implementation of OtherErrorHandler.
+// It simply writes a string representation of the given error into "w".
+func DefaultOtherErrorHandler(w http.ResponseWriter, _ *http.Request, msg string, code int) {
+	http.Error(w, msg, code)
+}