Add status package for reporting gRPC status and errors

call.go

@@ -43,6 +43,7 @@ import (
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/peer"
 	"google.golang.org/grpc/stats"
+	"google.golang.org/grpc/status"
 	"google.golang.org/grpc/transport"
 )
 
@@ -79,7 +80,7 @@ func recvResponse(ctx context.Context, dopts dialOptions, t transport.ClientTran
 			return
 		}
 	}
-	if inPayload != nil && err == io.EOF && stream.StatusCode() == codes.OK {
+	if inPayload != nil && err == io.EOF && stream.Status().Code() == codes.OK {
 		// TODO in the current implementation, inTrailer may be handled before inPayload in some cases.
 		// Fix the order if necessary.
 		dopts.copts.StatsHandler.HandleRPC(ctx, inPayload)
@@ -230,7 +231,7 @@ func invoke(ctx context.Context, method string, args, reply interface{}, cc *Cli
 		t, put, err = cc.getTransport(ctx, gopts)
 		if err != nil {
 			// TODO(zhaoq): Probably revisit the error handling.
-			if _, ok := err.(*rpcError); ok {
+			if _, ok := err.(status.Status); ok {
 				return err
 			}
 			if err == errConnClosing || err == errConnUnavailable {
@@ -284,6 +285,6 @@ func invoke(ctx context.Context, method string, args, reply interface{}, cc *Cli
 			put()
 			put = nil
 		}
-		return Errorf(stream.StatusCode(), "%s", stream.StatusDesc())
+		return stream.Status().Err()
 	}
 }

call_test.go

@@ -46,6 +46,7 @@ import (
 
 	"golang.org/x/net/context"
 	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/status"
 	"google.golang.org/grpc/transport"
 )
 
@@ -99,21 +100,21 @@ func (h *testStreamHandler) handleStream(t *testing.T, s *transport.Stream) {
 			return
 		}
 		if v == "weird error" {
-			h.t.WriteStatus(s, codes.Internal, weirdError)
+			h.t.WriteStatus(s, status.New(codes.Internal, weirdError))
 			return
 		}
 		if v == "canceled" {
 			canceled++
-			h.t.WriteStatus(s, codes.Internal, "")
+			h.t.WriteStatus(s, status.New(codes.Internal, ""))
 			return
 		}
 		if v == "port" {
-			h.t.WriteStatus(s, codes.Internal, h.port)
+			h.t.WriteStatus(s, status.New(codes.Internal, h.port))
 			return
 		}
 
 		if v != expectedRequest {
-			h.t.WriteStatus(s, codes.Internal, strings.Repeat("A", sizeLargeErr))
+			h.t.WriteStatus(s, status.New(codes.Internal, strings.Repeat("A", sizeLargeErr)))
 			return
 		}
 	}
@@ -124,7 +125,7 @@ func (h *testStreamHandler) handleStream(t *testing.T, s *transport.Stream) {
 		return
 	}
 	h.t.Write(s, reply, &transport.Options{})
-	h.t.WriteStatus(s, codes.OK, "")
+	h.t.WriteStatus(s, status.New(codes.OK, ""))
 }
 
 type server struct {
@@ -239,7 +240,7 @@ func TestInvokeLargeErr(t *testing.T) {
 	var reply string
 	req := "hello"
 	err := Invoke(context.Background(), "/foo/bar", &req, &reply, cc)
-	if _, ok := err.(*rpcError); !ok {
+	if _, ok := err.(status.Status); !ok {
 		t.Fatalf("grpc.Invoke(_, _, _, _, _) receives non rpc error.")
 	}
 	if Code(err) != codes.Internal || len(ErrorDesc(err)) != sizeLargeErr {
@@ -255,7 +256,7 @@ func TestInvokeErrorSpecialChars(t *testing.T) {
 	var reply string
 	req := "weird error"
 	err := Invoke(context.Background(), "/foo/bar", &req, &reply, cc)
-	if _, ok := err.(*rpcError); !ok {
+	if _, ok := err.(status.Status); !ok {
 		t.Fatalf("grpc.Invoke(_, _, _, _, _) receives non rpc error.")
 	}
 	if got, want := ErrorDesc(err), weirdError; got != want {

rpc_util.go

@@ -37,7 +37,6 @@ import (
 	"bytes"
 	"compress/gzip"
 	"encoding/binary"
-	"fmt"
 	"io"
 	"io/ioutil"
 	"math"
@@ -50,6 +49,7 @@ import (
 	"google.golang.org/grpc/metadata"
 	"google.golang.org/grpc/peer"
 	"google.golang.org/grpc/stats"
+	"google.golang.org/grpc/status"
 	"google.golang.org/grpc/transport"
 )
 
@@ -372,88 +372,56 @@ func recv(p *parser, c Codec, s *transport.Stream, dc Decompressor, m interface{
 	return nil
 }
 
-// rpcError defines the status from an RPC.
-type rpcError struct {
-	code codes.Code
-	desc string
-}
-
-func (e *rpcError) Error() string {
-	return fmt.Sprintf("rpc error: code = %s desc = %s", e.code, e.desc)
-}
-
 // Code returns the error code for err if it was produced by the rpc system.
 // Otherwise, it returns codes.Unknown.
+//
+// Deprecated; use status.FromError and Code method instead.
 func Code(err error) codes.Code {
-	if err == nil {
-		return codes.OK
-	}
-	if e, ok := err.(*rpcError); ok {
-		return e.code
+	if s, ok := status.FromError(err); ok {
+		return s.Code()
 	}
 	return codes.Unknown
 }
 
 // ErrorDesc returns the error description of err if it was produced by the rpc system.
 // Otherwise, it returns err.Error() or empty string when err is nil.
+//
+// Deprecated; use status.FromError and Message method instead.
 func ErrorDesc(err error) string {
-	if err == nil {
-		return ""
-	}
-	if e, ok := err.(*rpcError); ok {
-		return e.desc
+	if s, ok := status.FromError(err); ok {
+		return s.Message()
 	}
 	return err.Error()
 }
 
 // Errorf returns an error containing an error code and a description;
 // Errorf returns nil if c is OK.
+//
+// Deprecated; use status.Errorf instead.
 func Errorf(c codes.Code, format string, a ...interface{}) error {
-	if c == codes.OK {
-		return nil
-	}
-	return &rpcError{
-		code: c,
-		desc: fmt.Sprintf(format, a...),
-	}
+	return status.Errorf(c, format, a...)
 }
 
-// toRPCErr converts an error into a rpcError.
+// toRPCErr converts an error into an error from the status package.
 func toRPCErr(err error) error {
 	switch e := err.(type) {
-	case *rpcError:
+	case status.Status:
 		return err
 	case transport.StreamError:
-		return &rpcError{
-			code: e.Code,
-			desc: e.Desc,
-		}
+		return status.Error(e.Code, e.Desc)
 	case transport.ConnectionError:
-		return &rpcError{
-			code: codes.Internal,
-			desc: e.Desc,
-		}
+		return status.Error(codes.Internal, e.Desc)
 	default:
 		switch err {
 		case context.DeadlineExceeded:
-			return &rpcError{
-				code: codes.DeadlineExceeded,
-				desc: err.Error(),
-			}
+			return status.Error(codes.DeadlineExceeded, err.Error())
 		case context.Canceled:
-			return &rpcError{
-				code: codes.Canceled,
-				desc: err.Error(),
-			}
+			return status.Error(codes.Canceled, err.Error())
 		case ErrClientConnClosing:
-			return &rpcError{
-				code: codes.FailedPrecondition,
-				desc: err.Error(),
-			}
+			return status.Error(codes.FailedPrecondition, err.Error())
 		}
-
 	}
-	return Errorf(codes.Unknown, "%v", err)
+	return status.Error(codes.Unknown, err.Error())
 }
 
 // convertCode converts a standard Go error into its canonical code. Note that

rpc_util_test.go

@@ -41,8 +41,8 @@ import (
 	"testing"
 
 	"github.com/golang/protobuf/proto"
-	"golang.org/x/net/context"
 	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/status"
 	perfpb "google.golang.org/grpc/test/codec_perf"
 	"google.golang.org/grpc/transport"
 )
@@ -150,51 +150,21 @@ func TestToRPCErr(t *testing.T) {
 		// input
 		errIn error
 		// outputs
-		errOut *rpcError
+		errOut error
 	}{
-		{transport.StreamError{codes.Unknown, ""}, Errorf(codes.Unknown, "").(*rpcError)},
-		{transport.ErrConnClosing, Errorf(codes.Internal, transport.ErrConnClosing.Desc).(*rpcError)},
+		{transport.StreamError{Code: codes.Unknown, Desc: ""}, status.Error(codes.Unknown, "")},
+		{transport.ErrConnClosing, status.Error(codes.Internal, transport.ErrConnClosing.Desc)},
 	} {
 		err := toRPCErr(test.errIn)
-		rpcErr, ok := err.(*rpcError)
-		if !ok {
-			t.Fatalf("toRPCErr{%v} returned type %T, want %T", test.errIn, err, rpcError{})
+		if _, ok := err.(status.Status); !ok {
+			t.Fatalf("toRPCErr{%v} returned type %T, want %T", test.errIn, err, status.Error(codes.Unknown, ""))
 		}
-		if *rpcErr != *test.errOut {
+		if !reflect.DeepEqual(err, test.errOut) {
 			t.Fatalf("toRPCErr{%v} = %v \nwant %v", test.errIn, err, test.errOut)
 		}
 	}
 }
 
-func TestContextErr(t *testing.T) {
-	for _, test := range []struct {
-		// input
-		errIn error
-		// outputs
-		errOut transport.StreamError
-	}{
-		{context.DeadlineExceeded, transport.StreamError{codes.DeadlineExceeded, context.DeadlineExceeded.Error()}},
-		{context.Canceled, transport.StreamError{codes.Canceled, context.Canceled.Error()}},
-	} {
-		err := transport.ContextErr(test.errIn)
-		if err != test.errOut {
-			t.Fatalf("ContextErr{%v} = %v \nwant %v", test.errIn, err, test.errOut)
-		}
-	}
-}
-
-func TestErrorsWithSameParameters(t *testing.T) {
-	const description = "some description"
-	e1 := Errorf(codes.AlreadyExists, description).(*rpcError)
-	e2 := Errorf(codes.AlreadyExists, description).(*rpcError)
-	if e1 == e2 {
-		t.Fatalf("Error interfaces should not be considered equal - e1: %p - %v  e2: %p - %v", e1, e1, e2, e2)
-	}
-	if Code(e1) != Code(e2) || ErrorDesc(e1) != ErrorDesc(e2) {
-		t.Fatalf("Expected errors to have same code and description - e1: %p - %v  e2: %p - %v", e1, e1, e2, e2)
-	}
-}
-
 // bmEncode benchmarks encoding a Protocol Buffer message containing mSize
 // bytes.
 func bmEncode(b *testing.B, mSize int) {