pass micro errors from grpc server to grpc client (#1167)

* pass micro errors from grpc server to grpc client

Signed-off-by: Vasiliy Tolstov <v.tolstov@unistack.org>

* wrap micro errors.Error to grpc status

Signed-off-by: Vasiliy Tolstov <v.tolstov@unistack.org>

client/grpc/error.go

@@ -12,18 +12,22 @@ func microError(err error) error {
 		return nil
 	}
 
-	// micro error
-	if v, ok := err.(*errors.Error); ok {
-		return v
+	if verr, ok := err.(*errors.Error); ok {
+		return verr
 	}
 
 	// grpc error
 	if s, ok := status.FromError(err); ok {
+		details := s.Details()
+		if len(details) == 0 {
 			if e := errors.Parse(s.Message()); e.Code > 0 {
 				return e // actually a micro error
 			}
 			return errors.InternalServerError("go.micro.client", s.Message())
 		}
+		// return first error from details
+		return details[0].(error)
+	}
 
 	// do nothing
 	return err

client/grpc/grpc_test.go

@@ -7,6 +7,7 @@ import (
 
 	"github.com/micro/go-micro/v2/client"
 	"github.com/micro/go-micro/v2/client/selector"
+	"github.com/micro/go-micro/v2/errors"
 	"github.com/micro/go-micro/v2/registry"
 	"github.com/micro/go-micro/v2/registry/memory"
 	pgrpc "google.golang.org/grpc"
@@ -18,6 +19,9 @@ type greeterServer struct{}
 
 // SayHello implements helloworld.GreeterServer
 func (g *greeterServer) SayHello(ctx context.Context, in *pb.HelloRequest) (*pb.HelloReply, error) {
+	if in.Name == "Error" {
+		return nil, &errors.Error{Id: "1", Code: 99, Detail: "detail"}
+	}
 	return &pb.HelloReply{Message: "Hello " + in.Name}, nil
 }
 
@@ -84,4 +88,25 @@ func TestGRPCClient(t *testing.T) {
 			t.Fatalf("Got unexpected response %v", rsp.Message)
 		}
 	}
+
+	req := c.NewRequest("helloworld", "/helloworld.Greeter/SayHello", &pb.HelloRequest{
+		Name: "Error",
+	})
+
+	rsp := pb.HelloReply{}
+
+	err = c.Call(context.TODO(), req, &rsp)
+	if err == nil {
+		t.Fatal("nil error received")
+	}
+
+	verr, ok := err.(*errors.Error)
+	if !ok {
+		t.Fatalf("invalid error received %#+v\n", err)
+	}
+
+	if verr.Code != 99 && verr.Id != "1" && verr.Detail != "detail" {
+		t.Fatalf("invalid error received %#+v\n", verr)
+	}
+
 }

errors/errors.go

@@ -8,13 +8,7 @@ import (
 	"net/http"
 )
 
-// Error implements the error interface.
-type Error struct {
-	Id     string `json:"id"`
-	Code   int32  `json:"code"`
-	Detail string `json:"detail"`
-	Status string `json:"status"`
-}
+//go:generate protoc -I. --go_out=paths=source_relative:. errors.proto
 
 func (e *Error) Error() string {
 	b, _ := json.Marshal(e)

errors/errors.pb.go

@@ -0,0 +1,102 @@
+// Code generated by protoc-gen-go. DO NOT EDIT.
+// source: errors.proto
+
+package errors
+
+import (
+	fmt "fmt"
+	proto "github.com/golang/protobuf/proto"
+	math "math"
+)
+
+// Reference imports to suppress errors if they are not otherwise used.
+var _ = proto.Marshal
+var _ = fmt.Errorf
+var _ = math.Inf
+
+// This is a compile-time assertion to ensure that this generated file
+// is compatible with the proto package it is being compiled against.
+// A compilation error at this line likely means your copy of the
+// proto package needs to be updated.
+const _ = proto.ProtoPackageIsVersion3 // please upgrade the proto package
+
+type Error struct {
+	Id                   string   `protobuf:"bytes,1,opt,name=id,proto3" json:"id,omitempty"`
+	Code                 int32    `protobuf:"varint,2,opt,name=code,proto3" json:"code,omitempty"`
+	Detail               string   `protobuf:"bytes,3,opt,name=detail,proto3" json:"detail,omitempty"`
+	Status               string   `protobuf:"bytes,4,opt,name=status,proto3" json:"status,omitempty"`
+	XXX_NoUnkeyedLiteral struct{} `json:"-"`
+	XXX_unrecognized     []byte   `json:"-"`
+	XXX_sizecache        int32    `json:"-"`
+}
+
+func (m *Error) Reset()         { *m = Error{} }
+func (m *Error) String() string { return proto.CompactTextString(m) }
+func (*Error) ProtoMessage()    {}
+func (*Error) Descriptor() ([]byte, []int) {
+	return fileDescriptor_24fe73c7f0ddb19c, []int{0}
+}
+
+func (m *Error) XXX_Unmarshal(b []byte) error {
+	return xxx_messageInfo_Error.Unmarshal(m, b)
+}
+func (m *Error) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	return xxx_messageInfo_Error.Marshal(b, m, deterministic)
+}
+func (m *Error) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_Error.Merge(m, src)
+}
+func (m *Error) XXX_Size() int {
+	return xxx_messageInfo_Error.Size(m)
+}
+func (m *Error) XXX_DiscardUnknown() {
+	xxx_messageInfo_Error.DiscardUnknown(m)
+}
+
+var xxx_messageInfo_Error proto.InternalMessageInfo
+
+func (m *Error) GetId() string {
+	if m != nil {
+		return m.Id
+	}
+	return ""
+}
+
+func (m *Error) GetCode() int32 {
+	if m != nil {
+		return m.Code
+	}
+	return 0
+}
+
+func (m *Error) GetDetail() string {
+	if m != nil {
+		return m.Detail
+	}
+	return ""
+}
+
+func (m *Error) GetStatus() string {
+	if m != nil {
+		return m.Status
+	}
+	return ""
+}
+
+func init() {
+	proto.RegisterType((*Error)(nil), "errors.Error")
+}
+
+func init() { proto.RegisterFile("errors.proto", fileDescriptor_24fe73c7f0ddb19c) }
+
+var fileDescriptor_24fe73c7f0ddb19c = []byte{
+	// 116 bytes of a gzipped FileDescriptorProto
+	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0xe2, 0xe2, 0x49, 0x2d, 0x2a, 0xca,
+	0x2f, 0x2a, 0xd6, 0x2b, 0x28, 0xca, 0x2f, 0xc9, 0x17, 0x62, 0x83, 0xf0, 0x94, 0xa2, 0xb9, 0x58,
+	0x5d, 0x41, 0x2c, 0x21, 0x3e, 0x2e, 0xa6, 0xcc, 0x14, 0x09, 0x46, 0x05, 0x46, 0x0d, 0xce, 0x20,
+	0xa6, 0xcc, 0x14, 0x21, 0x21, 0x2e, 0x96, 0xe4, 0xfc, 0x94, 0x54, 0x09, 0x26, 0x05, 0x46, 0x0d,
+	0xd6, 0x20, 0x30, 0x5b, 0x48, 0x8c, 0x8b, 0x2d, 0x25, 0xb5, 0x24, 0x31, 0x33, 0x47, 0x82, 0x19,
+	0xac, 0x0e, 0xca, 0x03, 0x89, 0x17, 0x97, 0x24, 0x96, 0x94, 0x16, 0x4b, 0xb0, 0x40, 0xc4, 0x21,
+	0xbc, 0x24, 0x36, 0xb0, 0x5d, 0xc6, 0x80, 0x00, 0x00, 0x00, 0xff, 0xff, 0xef, 0xe7, 0x5d, 0xd3,
+	0x7b, 0x00, 0x00, 0x00,
+}

errors/errors.proto

@@ -0,0 +1,10 @@
+syntax = "proto3";
+
+package errors;
+
+message Error {
+  string id = 1;
+  int32 code = 2;
+  string detail = 3;
+  string status = 4;
+};

server/grpc/grpc.go

@@ -14,6 +14,7 @@ import (
 	"sync"
 	"time"
 
+	"github.com/golang/protobuf/proto"
 	"github.com/micro/go-micro/v2/broker"
 	"github.com/micro/go-micro/v2/codec"
 	"github.com/micro/go-micro/v2/errors"
@@ -375,20 +376,38 @@ func (g *grpcServer) processRequest(stream grpc.ServerStream, service *service,
 
 		statusCode := codes.OK
 		statusDesc := ""
-
 		// execute the handler
 		if appErr := fn(ctx, r, replyv.Interface()); appErr != nil {
-			if err, ok := appErr.(*rpcError); ok {
-				statusCode = err.code
-				statusDesc = err.desc
-			} else if err, ok := appErr.(*errors.Error); ok {
-				statusCode = microError(err)
-				statusDesc = appErr.Error()
-			} else {
+			var errStatus *status.Status
+			switch verr := appErr.(type) {
+			case *errors.Error:
+				// micro.Error now proto based and we can attach it to grpc status
+				statusCode = microError(verr)
+				statusDesc = verr.Error()
+				errStatus, err = status.New(statusCode, statusDesc).WithDetails(verr)
+				if err != nil {
+					return err
+				}
+			case proto.Message:
+				// user defined error that proto based we can attach it to grpc status
 				statusCode = convertCode(appErr)
 				statusDesc = appErr.Error()
+				errStatus, err = status.New(statusCode, statusDesc).WithDetails(verr)
+				if err != nil {
+					return err
 				}
-			return status.New(statusCode, statusDesc).Err()
+			case *rpcError:
+				// rpcError handling may be we have ability to attach it to details?
+				statusCode = verr.code
+				statusDesc = verr.desc
+				errStatus = status.New(statusCode, statusDesc)
+			default:
+				// default case user pass own error type that not proto based
+				statusCode = convertCode(verr)
+				statusDesc = verr.Error()
+				errStatus = status.New(statusCode, statusDesc)
+			}
+			return errStatus.Err()
 		}
 
 		if err := stream.SendMsg(replyv.Interface()); err != nil {
@@ -436,16 +455,37 @@ func (g *grpcServer) processStream(stream grpc.ServerStream, service *service, m
 
 	appErr := fn(ctx, r, ss)
 	if appErr != nil {
-		if err, ok := appErr.(*rpcError); ok {
-			statusCode = err.code
-			statusDesc = err.desc
-		} else if err, ok := appErr.(*errors.Error); ok {
-			statusCode = microError(err)
-			statusDesc = appErr.Error()
-		} else {
+		var err error
+		var errStatus *status.Status
+		switch verr := appErr.(type) {
+		case *errors.Error:
+			// micro.Error now proto based and we can attach it to grpc status
+			statusCode = microError(verr)
+			statusDesc = verr.Error()
+			errStatus, err = status.New(statusCode, statusDesc).WithDetails(verr)
+			if err != nil {
+				return err
+			}
+		case proto.Message:
+			// user defined error that proto based we can attach it to grpc status
 			statusCode = convertCode(appErr)
 			statusDesc = appErr.Error()
+			errStatus, err = status.New(statusCode, statusDesc).WithDetails(verr)
+			if err != nil {
+				return err
 			}
+		case *rpcError:
+			// rpcError handling may be we have ability to attach it to details?
+			statusCode = verr.code
+			statusDesc = verr.desc
+			errStatus = status.New(statusCode, statusDesc)
+		default:
+			// default case user pass own error type that not proto based
+			statusCode = convertCode(verr)
+			statusDesc = verr.Error()
+			errStatus = status.New(statusCode, statusDesc)
+		}
+		return errStatus.Err()
 	}
 
 	return status.New(statusCode, statusDesc).Err()

server/grpc/grpc_test.go

@@ -4,9 +4,11 @@ import (
 	"context"
 	"testing"
 
+	"github.com/micro/go-micro/v2/errors"
 	"github.com/micro/go-micro/v2/registry/memory"
 	"github.com/micro/go-micro/v2/server"
 	"google.golang.org/grpc"
+	"google.golang.org/grpc/status"
 
 	pb "github.com/micro/go-micro/v2/server/grpc/proto"
 )
@@ -16,6 +18,10 @@ type testServer struct{}
 
 // TestHello implements helloworld.GreeterServer
 func (s *testServer) Call(ctx context.Context, req *pb.Request, rsp *pb.Response) error {
+	if req.Name == "Error" {
+		return &errors.Error{Id: "1", Code: 99, Detail: "detail"}
+	}
+
 	rsp.Msg = "Hello " + req.Name
 	return nil
 }
@@ -63,4 +69,21 @@ func TestGRPCServer(t *testing.T) {
 			t.Fatalf("Got unexpected response %v", rsp.Msg)
 		}
 	}
+
+	// Test grpc error
+	rsp := pb.Response{}
+
+	if err := cc.Invoke(context.Background(), "/test.Test/Call", &pb.Request{Name: "Error"}, &rsp); err != nil {
+		st, ok := status.FromError(err)
+		if !ok {
+			t.Fatalf("invalid error received %#+v\n", err)
+		}
+		verr, ok := st.Details()[0].(*errors.Error)
+		if !ok {
+			t.Fatalf("invalid error received %#+v\n", st.Details()[0])
+		}
+		if verr.Code != 99 && verr.Id != "1" && verr.Detail != "detail" {
+			t.Fatalf("invalid error received %#+v\n", verr)
+		}
+	}
 }