gRPC: Use grpc-wasm as client package

grpc/backend/backend.go

@@ -38,3 +38,7 @@ func (b Backend) GetUser(ctx context.Context, req *server.GetUserRequest) (*serv
 		Id: req.GetUserId(),
 	}, nil
 }
+
+func (b Backend) GetUsers(req *server.GetUsersRequest, srv server.Backend_GetUsersServer) error {
+	return nil
+}

grpc/frontend/.gitignore

@@ -1 +0,0 @@
-html/test.wasm

grpc/frontend/frontend.go

@@ -1,28 +1,14 @@
 package main
 
 import (
-	"bufio"
-	"bytes"
 	"context"
-	"encoding/base64"
-	"encoding/binary"
-	"errors"
 	"fmt"
-	"io"
-	"net/http"
-	"strconv"
-	"strings"
-	"time"
 
-	"github.com/golang/protobuf/proto"
 	_ "google.golang.org/genproto/googleapis/rpc/errdetails"
-	spb "google.golang.org/genproto/googleapis/rpc/status"
-	"google.golang.org/grpc/codes"
-	"google.golang.org/grpc/metadata"
 	"google.golang.org/grpc/status"
 
-	"github.com/johanbrandhorst/fetch"
-	"github.com/johanbrandhorst/wasm-experiments/grpc/proto/server"
+	grpc "github.com/johanbrandhorst/grpc-wasm"
+	server "github.com/johanbrandhorst/wasm-experiments/grpc/proto/client"
 )
 
 // Build with Go WASM fork
@@ -33,220 +19,24 @@ import (
 //go:generate bash -c "go run assets_generate.go"
 
 func main() {
-	s := newClientConn("", "web.Backend")
-	req := &server.GetUserRequest{
+	cc, _ := grpc.Dial("")
+	client := server.NewBackendClient(cc)
+	resp, err := client.GetUser(context.Background(), &server.GetUserRequest{
 		UserId: "1234",
-	}
-	resp := new(server.User)
-	err := s.Invoke(context.Background(), "GetUser", req, resp)
+	})
 	if err != nil {
 		st := status.Convert(err)
 		fmt.Println(st.Code(), st.Message(), st.Details())
-		return
-	}
-	fmt.Println(resp.GetId())
-	req.UserId = "123"
-	err = s.Invoke(context.Background(), "GetUser", req, resp)
-	if err != nil {
-		st := status.Convert(err)
-		fmt.Println(st.Code(), st.Message(), st.Details())
-		return
-	}
-	fmt.Println(resp.GetId())
-}
-
-type ClientConn struct {
-	client  *http.Client
-	service string
-	host    string
-}
-
-func newClientConn(host, service string) *ClientConn {
-	return &ClientConn{
-		client: &http.Client{
-			Transport: &fetch.Transport{},
-		},
-		service: service,
-		host:    host,
-	}
-}
-
-func (cc *ClientConn) Invoke(ctx context.Context, method string, in, out proto.Message) error {
-	b, err := proto.Marshal(in)
-	if err != nil {
-		return status.Error(codes.Internal, err.Error())
-	}
-
-	bufHeader := make([]byte, 5)
-
-	// Write length of b into buf
-	binary.BigEndian.PutUint32(bufHeader[1:], uint32(len(b)))
-
-	req, err := http.NewRequest(
-		"POST",
-		strings.Join([]string{cc.host, cc.service, method}, "/"),
-		bytes.NewBuffer(append(bufHeader, b...)),
-	)
-	if err != nil {
-		return status.Error(codes.Internal, err.Error())
-	}
-	req = req.WithContext(ctx)
-	addHeaders(req)
-
-	resp, err := cc.client.Do(req)
-	if err != nil {
-		return status.Error(codes.Internal, err.Error())
-	}
-	defer resp.Body.Close()
-
-	st := statusFromHeaders(resp.Header)
-	if st.Code() != codes.OK {
-		return st.Err()
-	}
-
-	msgHeader := make([]byte, 5)
-	for {
-		_, err := resp.Body.Read(msgHeader)
-		if err != nil {
-			return status.Error(codes.Internal, err.Error())
-		}
-		// 1 in MSB signifies that this is the trailer. Break loop.
-		// https://github.com/grpc/grpc/blob/master/doc/PROTOCOL-WEB.md#protocol-differences-vs-grpc-over-http2
-		if msgHeader[0]>>7 == 1 {
-			break
-		}
-
-		msgLen := binary.BigEndian.Uint32(msgHeader[1:])
-
-		msg := make([]byte, msgLen)
-		_, err = resp.Body.Read(msg)
-		if err != nil {
-			return status.Error(codes.Internal, err.Error())
-		}
-		err = proto.Unmarshal(msg, out)
-		if err != nil {
-			return status.Error(codes.Internal, err.Error())
-		}
-	}
-
-	if msgHeader[0]&1 == 0 {
-		trailers, err := readTrailers(resp.Body)
-		if err != nil {
-			return status.Error(codes.Internal, err.Error())
-		}
-		st = statusFromHeaders(trailers)
-		if st.Code() != codes.OK {
-			return st.Err()
-		}
 	} else {
-		// TODO(johanbrandhorst): Support compressed trailers
+		fmt.Println(resp.GetId())
 	}
-
-	return nil
-}
-
-func addHeaders(req *http.Request) {
-	// TODO: Add more headers
-	// https://github.com/grpc/grpc-go/blob/590da37e2dfb4705d8ebd9574ce4cb75295d9674/transport/http2_client.go#L356
-	req.Header.Add("content-type", "application/grpc-web+proto")
-	if dl, ok := req.Context().Deadline(); ok {
-		timeout := dl.Sub(time.Now())
-		req.Header.Add("grpc-timeout", encodeTimeout(timeout))
-	}
-	md, ok := metadata.FromOutgoingContext(req.Context())
-	if ok {
-		for h, vs := range md {
-			for _, v := range vs {
-				req.Header.Add(h, v)
-			}
-		}
+	resp, err = client.GetUser(context.Background(), &server.GetUserRequest{
+		UserId: "123",
+	})
+	if err != nil {
+		st := status.Convert(err)
+		fmt.Println(st.Code(), st.Message(), st.Details())
+	} else {
+		fmt.Println(resp.GetId())
 	}
 }
-
-const maxTimeoutValue int64 = 100000000 - 1
-
-// Copied from grpc-go
-// https://github.com/grpc/grpc-go/blob/590da37e2dfb4705d8ebd9574ce4cb75295d9674/transport/http_util.go#L388
-// div does integer division and round-up the result. Note that this is
-// equivalent to (d+r-1)/r but has less chance to overflow.
-func div(d, r time.Duration) int64 {
-	if m := d % r; m > 0 {
-		return int64(d/r + 1)
-	}
-	return int64(d / r)
-}
-
-// Copied from grpc-go
-// https://github.com/grpc/grpc-go/blob/590da37e2dfb4705d8ebd9574ce4cb75295d9674/transport/http_util.go#L398
-func encodeTimeout(t time.Duration) string {
-	if t <= 0 {
-		return "0n"
-	}
-	if d := div(t, time.Nanosecond); d <= maxTimeoutValue {
-		return strconv.FormatInt(d, 10) + "n"
-	}
-	if d := div(t, time.Microsecond); d <= maxTimeoutValue {
-		return strconv.FormatInt(d, 10) + "u"
-	}
-	if d := div(t, time.Millisecond); d <= maxTimeoutValue {
-		return strconv.FormatInt(d, 10) + "m"
-	}
-	if d := div(t, time.Second); d <= maxTimeoutValue {
-		return strconv.FormatInt(d, 10) + "S"
-	}
-	if d := div(t, time.Minute); d <= maxTimeoutValue {
-		return strconv.FormatInt(d, 10) + "M"
-	}
-	// Note that maxTimeoutValue * time.Hour > MaxInt64.
-	return strconv.FormatInt(div(t, time.Hour), 10) + "H"
-}
-
-// Copied from grpc-go
-// https://github.com/grpc/grpc-go/blob/b94ea975f3beb73799fac17cc24ee923fcd3cb5c/transport/http_util.go#L213
-func decodeBinHeader(v string) ([]byte, error) {
-	if len(v)%4 == 0 {
-		// Input was padded, or padding was not necessary.
-		return base64.StdEncoding.DecodeString(v)
-	}
-	return base64.RawStdEncoding.DecodeString(v)
-}
-
-func readTrailers(in io.Reader) (http.Header, error) {
-	s := bufio.NewScanner(in)
-	trailers := http.Header{}
-	for s.Scan() {
-		v := s.Text()
-		kv := strings.SplitN(v, ": ", 2)
-		if len(kv) != 2 {
-			return nil, errors.New("malformed header: " + v)
-		}
-		trailers.Add(kv[0], kv[1])
-	}
-
-	return trailers, s.Err()
-}
-
-func statusFromHeaders(h http.Header) *status.Status {
-	details := h.Get("grpc-status-details-bin")
-	if details != "" {
-		b, err := decodeBinHeader(details)
-		if err != nil {
-			return status.New(codes.Internal, "malformed grps-status-details-bin header: "+err.Error())
-		}
-		s := &spb.Status{}
-		err = proto.Unmarshal(b, s)
-		if err != nil {
-			return status.New(codes.Internal, "malformed grps-status-details-bin header: "+err.Error())
-		}
-		return status.FromProto(s)
-	}
-	sh := h.Get("grpc-status")
-	if sh != "" {
-		val, err := strconv.Atoi(sh)
-		if err != nil {
-			return status.New(codes.Internal, "malformed grpc-status header: "+err.Error())
-		}
-		return status.New(codes.Code(val), h.Get("grpc-message"))
-	}
-	return status.New(codes.OK, "")
-}

grpc/proto/client/web.pb.go

@@ -12,8 +12,8 @@ import fmt "fmt"
 import math "math"
 
 import (
+	grpc "github.com/johanbrandhorst/grpc-wasm"
 	context "golang.org/x/net/context"
-	grpc "google.golang.org/grpc"
 )
 
 // Reference imports to suppress errors if they are not otherwise used.
@@ -38,7 +38,7 @@ func (m *GetUserRequest) Reset()         { *m = GetUserRequest{} }
 func (m *GetUserRequest) String() string { return proto.CompactTextString(m) }
 func (*GetUserRequest) ProtoMessage()    {}
 func (*GetUserRequest) Descriptor() ([]byte, []int) {
-	return fileDescriptor_web_19a831568a3bf959, []int{0}
+	return fileDescriptor_web_87670d45010119fa, []int{0}
 }
 func (m *GetUserRequest) XXX_Unmarshal(b []byte) error {
 	return xxx_messageInfo_GetUserRequest.Unmarshal(m, b)
@@ -76,7 +76,7 @@ func (m *User) Reset()         { *m = User{} }
 func (m *User) String() string { return proto.CompactTextString(m) }
 func (*User) ProtoMessage()    {}
 func (*User) Descriptor() ([]byte, []int) {
-	return fileDescriptor_web_19a831568a3bf959, []int{1}
+	return fileDescriptor_web_87670d45010119fa, []int{1}
 }
 func (m *User) XXX_Unmarshal(b []byte) error {
 	return xxx_messageInfo_User.Unmarshal(m, b)
@@ -103,9 +103,48 @@ func (m *User) GetId() string {
 	return ""
 }
 
+type GetUsersRequest struct {
+	NumUsers             int64    `protobuf:"varint,1,opt,name=num_users,json=numUsers" json:"num_users,omitempty"`
+	XXX_NoUnkeyedLiteral struct{} `json:"-"`
+	XXX_unrecognized     []byte   `json:"-"`
+	XXX_sizecache        int32    `json:"-"`
+}
+
+func (m *GetUsersRequest) Reset()         { *m = GetUsersRequest{} }
+func (m *GetUsersRequest) String() string { return proto.CompactTextString(m) }
+func (*GetUsersRequest) ProtoMessage()    {}
+func (*GetUsersRequest) Descriptor() ([]byte, []int) {
+	return fileDescriptor_web_87670d45010119fa, []int{2}
+}
+func (m *GetUsersRequest) XXX_Unmarshal(b []byte) error {
+	return xxx_messageInfo_GetUsersRequest.Unmarshal(m, b)
+}
+func (m *GetUsersRequest) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	return xxx_messageInfo_GetUsersRequest.Marshal(b, m, deterministic)
+}
+func (dst *GetUsersRequest) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_GetUsersRequest.Merge(dst, src)
+}
+func (m *GetUsersRequest) XXX_Size() int {
+	return xxx_messageInfo_GetUsersRequest.Size(m)
+}
+func (m *GetUsersRequest) XXX_DiscardUnknown() {
+	xxx_messageInfo_GetUsersRequest.DiscardUnknown(m)
+}
+
+var xxx_messageInfo_GetUsersRequest proto.InternalMessageInfo
+
+func (m *GetUsersRequest) GetNumUsers() int64 {
+	if m != nil {
+		return m.NumUsers
+	}
+	return 0
+}
+
 func init() {
 	proto.RegisterType((*GetUserRequest)(nil), "web.GetUserRequest")
 	proto.RegisterType((*User)(nil), "web.User")
+	proto.RegisterType((*GetUsersRequest)(nil), "web.GetUsersRequest")
 }
 
 // Reference imports to suppress errors if they are not otherwise used.
@@ -121,6 +160,7 @@ const _ = grpc.SupportPackageIsVersion4
 // For semantics around ctx use and closing/ending streaming RPCs, please refer to https://godoc.org/google.golang.org/grpc#ClientConn.NewStream.
 type BackendClient interface {
 	GetUser(ctx context.Context, in *GetUserRequest, opts ...grpc.CallOption) (*User, error)
+	GetUsers(ctx context.Context, in *GetUsersRequest, opts ...grpc.CallOption) (Backend_GetUsersClient, error)
 }
 
 type backendClient struct {
@@ -140,9 +180,42 @@ func (c *backendClient) GetUser(ctx context.Context, in *GetUserRequest, opts ..
 	return out, nil
 }
 
+func (c *backendClient) GetUsers(ctx context.Context, in *GetUsersRequest, opts ...grpc.CallOption) (Backend_GetUsersClient, error) {
+	stream, err := c.cc.NewStream(ctx, &_Backend_serviceDesc.Streams[0], "/web.Backend/GetUsers", opts...)
+	if err != nil {
+		return nil, err
+	}
+	x := &backendGetUsersClient{stream}
+	if err := x.ClientStream.SendMsg(in); err != nil {
+		return nil, err
+	}
+	if err := x.ClientStream.CloseSend(); err != nil {
+		return nil, err
+	}
+	return x, nil
+}
+
+type Backend_GetUsersClient interface {
+	Recv() (*User, error)
+	grpc.ClientStream
+}
+
+type backendGetUsersClient struct {
+	grpc.ClientStream
+}
+
+func (x *backendGetUsersClient) Recv() (*User, error) {
+	m := new(User)
+	if err := x.ClientStream.RecvMsg(m); err != nil {
+		return nil, err
+	}
+	return m, nil
+}
+
 // BackendServer is the server API for Backend service.
 type BackendServer interface {
 	GetUser(context.Context, *GetUserRequest) (*User, error)
+	GetUsers(*GetUsersRequest, Backend_GetUsersServer) error
 }
 
 func RegisterBackendServer(s *grpc.Server, srv BackendServer) {
@@ -167,6 +240,27 @@ func _Backend_GetUser_Handler(srv interface{}, ctx context.Context, dec func(int
 	return interceptor(ctx, in, info, handler)
 }
 
+func _Backend_GetUsers_Handler(srv interface{}, stream grpc.ServerStream) error {
+	m := new(GetUsersRequest)
+	if err := stream.RecvMsg(m); err != nil {
+		return err
+	}
+	return srv.(BackendServer).GetUsers(m, &backendGetUsersServer{stream})
+}
+
+type Backend_GetUsersServer interface {
+	Send(*User) error
+	grpc.ServerStream
+}
+
+type backendGetUsersServer struct {
+	grpc.ServerStream
+}
+
+func (x *backendGetUsersServer) Send(m *User) error {
+	return x.ServerStream.SendMsg(m)
+}
+
 var _Backend_serviceDesc = grpc.ServiceDesc{
 	ServiceName: "web.Backend",
 	HandlerType: (*BackendServer)(nil),
@@ -176,25 +270,33 @@ var _Backend_serviceDesc = grpc.ServiceDesc{
 			Handler:    _Backend_GetUser_Handler,
 		},
 	},
-	Streams:  []grpc.StreamDesc{},
+	Streams: []grpc.StreamDesc{
+		{
+			StreamName:    "GetUsers",
+			Handler:       _Backend_GetUsers_Handler,
+			ServerStreams: true,
+		},
+	},
 	Metadata: "proto/web.proto",
 }
 
-func init() { proto.RegisterFile("proto/web.proto", fileDescriptor_web_19a831568a3bf959) }
+func init() { proto.RegisterFile("proto/web.proto", fileDescriptor_web_87670d45010119fa) }
 
-var fileDescriptor_web_19a831568a3bf959 = []byte{
-	// 197 bytes of a gzipped FileDescriptorProto
-	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0xe2, 0xe2, 0x2f, 0x28, 0xca, 0x2f,
-	0xc9, 0xd7, 0x2f, 0x4f, 0x4d, 0xd2, 0x03, 0xb3, 0x84, 0x98, 0xcb, 0x53, 0x93, 0x94, 0x34, 0xb9,
-	0xf8, 0xdc, 0x53, 0x4b, 0x42, 0x8b, 0x53, 0x8b, 0x82, 0x52, 0x0b, 0x4b, 0x53, 0x8b, 0x4b, 0x84,
-	0xc4, 0xb9, 0xd8, 0x4b, 0x8b, 0x53, 0x8b, 0xe2, 0x33, 0x53, 0x24, 0x18, 0x15, 0x18, 0x35, 0x38,
-	0x83, 0xd8, 0x40, 0x5c, 0xcf, 0x14, 0x25, 0x31, 0x2e, 0x16, 0x90, 0x3a, 0x21, 0x3e, 0x2e, 0x26,
-	0xb8, 0x1c, 0x53, 0x66, 0x8a, 0x91, 0x19, 0x17, 0xbb, 0x53, 0x62, 0x72, 0x76, 0x6a, 0x5e, 0x8a,
-	0x90, 0x36, 0x17, 0x3b, 0xd4, 0x34, 0x21, 0x61, 0x3d, 0x90, 0x4d, 0xa8, 0x66, 0x4b, 0x71, 0x82,
-	0x05, 0x41, 0x22, 0x4a, 0x0c, 0x4e, 0xf6, 0x51, 0xb6, 0xe9, 0x99, 0x25, 0x19, 0xa5, 0x49, 0x7a,
-	0xc9, 0xf9, 0xb9, 0xfa, 0x59, 0xf9, 0x19, 0x89, 0x79, 0x49, 0x45, 0x89, 0x79, 0x29, 0x19, 0xf9,
-	0x45, 0xc5, 0x25, 0xfa, 0xe5, 0x89, 0xc5, 0xb9, 0xba, 0xa9, 0x15, 0x05, 0xa9, 0x45, 0x99, 0xb9,
-	0xa9, 0x79, 0x25, 0xc5, 0xfa, 0xe9, 0x45, 0x05, 0xc9, 0xfa, 0x10, 0x3f, 0x14, 0xa7, 0x16, 0x95,
-	0xa5, 0x16, 0x25, 0xb1, 0x81, 0x79, 0xc6, 0x80, 0x00, 0x00, 0x00, 0xff, 0xff, 0x00, 0x64, 0xf1,
-	0x41, 0xda, 0x00, 0x00, 0x00,
+var fileDescriptor_web_87670d45010119fa = []byte{
+	// 236 bytes of a gzipped FileDescriptorProto
+	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0x6c, 0x90, 0xc1, 0x4b, 0xc3, 0x30,
+	0x18, 0xc5, 0xdd, 0x26, 0xeb, 0xfa, 0x1d, 0x36, 0x88, 0xa2, 0xa2, 0x17, 0xe9, 0x49, 0x11, 0x1b,
+	0xd1, 0xb3, 0x08, 0xbb, 0x88, 0xd7, 0x82, 0x17, 0x2f, 0xa3, 0x69, 0x3e, 0xda, 0x2a, 0x49, 0xea,
+	0xf7, 0x25, 0xd6, 0x3f, 0x5f, 0x12, 0x37, 0x51, 0xf0, 0x96, 0xf7, 0xf2, 0x7b, 0x2f, 0x8f, 0xc0,
+	0x6a, 0x20, 0xe7, 0x9d, 0x1c, 0x51, 0x95, 0xe9, 0x24, 0x66, 0x23, 0xaa, 0xe2, 0x12, 0x96, 0x8f,
+	0xe8, 0x9f, 0x19, 0xa9, 0xc2, 0xf7, 0x80, 0xec, 0xc5, 0x31, 0x64, 0x81, 0x91, 0x36, 0xbd, 0x3e,
+	0x99, 0x9c, 0x4f, 0x2e, 0xf2, 0x6a, 0x1e, 0xe5, 0x93, 0x2e, 0x8e, 0x60, 0x3f, 0x72, 0x62, 0x09,
+	0xd3, 0x9f, 0xbb, 0x69, 0xaf, 0x8b, 0x12, 0x56, 0xdb, 0x0a, 0xde, 0x75, 0x9c, 0x41, 0x6e, 0x83,
+	0xd9, 0xc4, 0x20, 0x27, 0x72, 0x56, 0x2d, 0x6c, 0x30, 0x89, 0xb9, 0x6d, 0x21, 0x5b, 0xd7, 0xcd,
+	0x1b, 0x5a, 0x2d, 0xae, 0x20, 0xdb, 0x46, 0xc5, 0x41, 0x19, 0x97, 0xfd, 0xdd, 0x72, 0x9a, 0x27,
+	0x33, 0x3a, 0xc5, 0x9e, 0x90, 0xb0, 0xd8, 0xbd, 0x23, 0x0e, 0x7f, 0xd3, 0xfc, 0x1f, 0x7e, 0x33,
+	0x59, 0x3f, 0xbc, 0xdc, 0xb7, 0xbd, 0xef, 0x82, 0x2a, 0x1b, 0x67, 0xe4, 0xab, 0xeb, 0x6a, 0xab,
+	0xa8, 0xb6, 0xba, 0x73, 0xc4, 0x5e, 0x8e, 0x35, 0x9b, 0x6b, 0xfc, 0x1c, 0x90, 0x7a, 0x83, 0xd6,
+	0xb3, 0x6c, 0x69, 0x68, 0xe4, 0xf7, 0x27, 0x31, 0xd2, 0x07, 0x92, 0x9a, 0x27, 0x75, 0xf7, 0x15,
+	0x00, 0x00, 0xff, 0xff, 0x75, 0x28, 0x26, 0x8f, 0x3b, 0x01, 0x00, 0x00,
 }

grpc/proto/server/web.pb.go

@@ -38,7 +38,7 @@ func (m *GetUserRequest) Reset()         { *m = GetUserRequest{} }
 func (m *GetUserRequest) String() string { return proto.CompactTextString(m) }
 func (*GetUserRequest) ProtoMessage()    {}
 func (*GetUserRequest) Descriptor() ([]byte, []int) {
-	return fileDescriptor_web_19a831568a3bf959, []int{0}
+	return fileDescriptor_web_87670d45010119fa, []int{0}
 }
 func (m *GetUserRequest) XXX_Unmarshal(b []byte) error {
 	return xxx_messageInfo_GetUserRequest.Unmarshal(m, b)
@@ -76,7 +76,7 @@ func (m *User) Reset()         { *m = User{} }
 func (m *User) String() string { return proto.CompactTextString(m) }
 func (*User) ProtoMessage()    {}
 func (*User) Descriptor() ([]byte, []int) {
-	return fileDescriptor_web_19a831568a3bf959, []int{1}
+	return fileDescriptor_web_87670d45010119fa, []int{1}
 }
 func (m *User) XXX_Unmarshal(b []byte) error {
 	return xxx_messageInfo_User.Unmarshal(m, b)
@@ -103,9 +103,48 @@ func (m *User) GetId() string {
 	return ""
 }
 
+type GetUsersRequest struct {
+	NumUsers             int64    `protobuf:"varint,1,opt,name=num_users,json=numUsers" json:"num_users,omitempty"`
+	XXX_NoUnkeyedLiteral struct{} `json:"-"`
+	XXX_unrecognized     []byte   `json:"-"`
+	XXX_sizecache        int32    `json:"-"`
+}
+
+func (m *GetUsersRequest) Reset()         { *m = GetUsersRequest{} }
+func (m *GetUsersRequest) String() string { return proto.CompactTextString(m) }
+func (*GetUsersRequest) ProtoMessage()    {}
+func (*GetUsersRequest) Descriptor() ([]byte, []int) {
+	return fileDescriptor_web_87670d45010119fa, []int{2}
+}
+func (m *GetUsersRequest) XXX_Unmarshal(b []byte) error {
+	return xxx_messageInfo_GetUsersRequest.Unmarshal(m, b)
+}
+func (m *GetUsersRequest) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	return xxx_messageInfo_GetUsersRequest.Marshal(b, m, deterministic)
+}
+func (dst *GetUsersRequest) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_GetUsersRequest.Merge(dst, src)
+}
+func (m *GetUsersRequest) XXX_Size() int {
+	return xxx_messageInfo_GetUsersRequest.Size(m)
+}
+func (m *GetUsersRequest) XXX_DiscardUnknown() {
+	xxx_messageInfo_GetUsersRequest.DiscardUnknown(m)
+}
+
+var xxx_messageInfo_GetUsersRequest proto.InternalMessageInfo
+
+func (m *GetUsersRequest) GetNumUsers() int64 {
+	if m != nil {
+		return m.NumUsers
+	}
+	return 0
+}
+
 func init() {
 	proto.RegisterType((*GetUserRequest)(nil), "web.GetUserRequest")
 	proto.RegisterType((*User)(nil), "web.User")
+	proto.RegisterType((*GetUsersRequest)(nil), "web.GetUsersRequest")
 }
 
 // Reference imports to suppress errors if they are not otherwise used.
@@ -121,6 +160,7 @@ const _ = grpc.SupportPackageIsVersion4
 // For semantics around ctx use and closing/ending streaming RPCs, please refer to https://godoc.org/google.golang.org/grpc#ClientConn.NewStream.
 type BackendClient interface {
 	GetUser(ctx context.Context, in *GetUserRequest, opts ...grpc.CallOption) (*User, error)
+	GetUsers(ctx context.Context, in *GetUsersRequest, opts ...grpc.CallOption) (Backend_GetUsersClient, error)
 }
 
 type backendClient struct {
@@ -140,9 +180,42 @@ func (c *backendClient) GetUser(ctx context.Context, in *GetUserRequest, opts ..
 	return out, nil
 }
 
+func (c *backendClient) GetUsers(ctx context.Context, in *GetUsersRequest, opts ...grpc.CallOption) (Backend_GetUsersClient, error) {
+	stream, err := c.cc.NewStream(ctx, &_Backend_serviceDesc.Streams[0], "/web.Backend/GetUsers", opts...)
+	if err != nil {
+		return nil, err
+	}
+	x := &backendGetUsersClient{stream}
+	if err := x.ClientStream.SendMsg(in); err != nil {
+		return nil, err
+	}
+	if err := x.ClientStream.CloseSend(); err != nil {
+		return nil, err
+	}
+	return x, nil
+}
+
+type Backend_GetUsersClient interface {
+	Recv() (*User, error)
+	grpc.ClientStream
+}
+
+type backendGetUsersClient struct {
+	grpc.ClientStream
+}
+
+func (x *backendGetUsersClient) Recv() (*User, error) {
+	m := new(User)
+	if err := x.ClientStream.RecvMsg(m); err != nil {
+		return nil, err
+	}
+	return m, nil
+}
+
 // BackendServer is the server API for Backend service.
 type BackendServer interface {
 	GetUser(context.Context, *GetUserRequest) (*User, error)
+	GetUsers(*GetUsersRequest, Backend_GetUsersServer) error
 }
 
 func RegisterBackendServer(s *grpc.Server, srv BackendServer) {
@@ -167,6 +240,27 @@ func _Backend_GetUser_Handler(srv interface{}, ctx context.Context, dec func(int
 	return interceptor(ctx, in, info, handler)
 }
 
+func _Backend_GetUsers_Handler(srv interface{}, stream grpc.ServerStream) error {
+	m := new(GetUsersRequest)
+	if err := stream.RecvMsg(m); err != nil {
+		return err
+	}
+	return srv.(BackendServer).GetUsers(m, &backendGetUsersServer{stream})
+}
+
+type Backend_GetUsersServer interface {
+	Send(*User) error
+	grpc.ServerStream
+}
+
+type backendGetUsersServer struct {
+	grpc.ServerStream
+}
+
+func (x *backendGetUsersServer) Send(m *User) error {
+	return x.ServerStream.SendMsg(m)
+}
+
 var _Backend_serviceDesc = grpc.ServiceDesc{
 	ServiceName: "web.Backend",
 	HandlerType: (*BackendServer)(nil),
@@ -176,25 +270,33 @@ var _Backend_serviceDesc = grpc.ServiceDesc{
 			Handler:    _Backend_GetUser_Handler,
 		},
 	},
-	Streams:  []grpc.StreamDesc{},
+	Streams: []grpc.StreamDesc{
+		{
+			StreamName:    "GetUsers",
+			Handler:       _Backend_GetUsers_Handler,
+			ServerStreams: true,
+		},
+	},
 	Metadata: "proto/web.proto",
 }
 
-func init() { proto.RegisterFile("proto/web.proto", fileDescriptor_web_19a831568a3bf959) }
+func init() { proto.RegisterFile("proto/web.proto", fileDescriptor_web_87670d45010119fa) }
 
-var fileDescriptor_web_19a831568a3bf959 = []byte{
-	// 197 bytes of a gzipped FileDescriptorProto
-	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0xe2, 0xe2, 0x2f, 0x28, 0xca, 0x2f,
-	0xc9, 0xd7, 0x2f, 0x4f, 0x4d, 0xd2, 0x03, 0xb3, 0x84, 0x98, 0xcb, 0x53, 0x93, 0x94, 0x34, 0xb9,
-	0xf8, 0xdc, 0x53, 0x4b, 0x42, 0x8b, 0x53, 0x8b, 0x82, 0x52, 0x0b, 0x4b, 0x53, 0x8b, 0x4b, 0x84,
-	0xc4, 0xb9, 0xd8, 0x4b, 0x8b, 0x53, 0x8b, 0xe2, 0x33, 0x53, 0x24, 0x18, 0x15, 0x18, 0x35, 0x38,
-	0x83, 0xd8, 0x40, 0x5c, 0xcf, 0x14, 0x25, 0x31, 0x2e, 0x16, 0x90, 0x3a, 0x21, 0x3e, 0x2e, 0x26,
-	0xb8, 0x1c, 0x53, 0x66, 0x8a, 0x91, 0x19, 0x17, 0xbb, 0x53, 0x62, 0x72, 0x76, 0x6a, 0x5e, 0x8a,
-	0x90, 0x36, 0x17, 0x3b, 0xd4, 0x34, 0x21, 0x61, 0x3d, 0x90, 0x4d, 0xa8, 0x66, 0x4b, 0x71, 0x82,
-	0x05, 0x41, 0x22, 0x4a, 0x0c, 0x4e, 0xf6, 0x51, 0xb6, 0xe9, 0x99, 0x25, 0x19, 0xa5, 0x49, 0x7a,
-	0xc9, 0xf9, 0xb9, 0xfa, 0x59, 0xf9, 0x19, 0x89, 0x79, 0x49, 0x45, 0x89, 0x79, 0x29, 0x19, 0xf9,
-	0x45, 0xc5, 0x25, 0xfa, 0xe5, 0x89, 0xc5, 0xb9, 0xba, 0xa9, 0x15, 0x05, 0xa9, 0x45, 0x99, 0xb9,
-	0xa9, 0x79, 0x25, 0xc5, 0xfa, 0xe9, 0x45, 0x05, 0xc9, 0xfa, 0x10, 0x3f, 0x14, 0xa7, 0x16, 0x95,
-	0xa5, 0x16, 0x25, 0xb1, 0x81, 0x79, 0xc6, 0x80, 0x00, 0x00, 0x00, 0xff, 0xff, 0x00, 0x64, 0xf1,
-	0x41, 0xda, 0x00, 0x00, 0x00,
+var fileDescriptor_web_87670d45010119fa = []byte{
+	// 236 bytes of a gzipped FileDescriptorProto
+	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0x6c, 0x90, 0xc1, 0x4b, 0xc3, 0x30,
+	0x18, 0xc5, 0xdd, 0x26, 0xeb, 0xfa, 0x1d, 0x36, 0x88, 0xa2, 0xa2, 0x17, 0xe9, 0x49, 0x11, 0x1b,
+	0xd1, 0xb3, 0x08, 0xbb, 0x88, 0xd7, 0x82, 0x17, 0x2f, 0xa3, 0x69, 0x3e, 0xda, 0x2a, 0x49, 0xea,
+	0xf7, 0x25, 0xd6, 0x3f, 0x5f, 0x12, 0x37, 0x51, 0xf0, 0x96, 0xf7, 0xf2, 0x7b, 0x2f, 0x8f, 0xc0,
+	0x6a, 0x20, 0xe7, 0x9d, 0x1c, 0x51, 0x95, 0xe9, 0x24, 0x66, 0x23, 0xaa, 0xe2, 0x12, 0x96, 0x8f,
+	0xe8, 0x9f, 0x19, 0xa9, 0xc2, 0xf7, 0x80, 0xec, 0xc5, 0x31, 0x64, 0x81, 0x91, 0x36, 0xbd, 0x3e,
+	0x99, 0x9c, 0x4f, 0x2e, 0xf2, 0x6a, 0x1e, 0xe5, 0x93, 0x2e, 0x8e, 0x60, 0x3f, 0x72, 0x62, 0x09,
+	0xd3, 0x9f, 0xbb, 0x69, 0xaf, 0x8b, 0x12, 0x56, 0xdb, 0x0a, 0xde, 0x75, 0x9c, 0x41, 0x6e, 0x83,
+	0xd9, 0xc4, 0x20, 0x27, 0x72, 0x56, 0x2d, 0x6c, 0x30, 0x89, 0xb9, 0x6d, 0x21, 0x5b, 0xd7, 0xcd,
+	0x1b, 0x5a, 0x2d, 0xae, 0x20, 0xdb, 0x46, 0xc5, 0x41, 0x19, 0x97, 0xfd, 0xdd, 0x72, 0x9a, 0x27,
+	0x33, 0x3a, 0xc5, 0x9e, 0x90, 0xb0, 0xd8, 0xbd, 0x23, 0x0e, 0x7f, 0xd3, 0xfc, 0x1f, 0x7e, 0x33,
+	0x59, 0x3f, 0xbc, 0xdc, 0xb7, 0xbd, 0xef, 0x82, 0x2a, 0x1b, 0x67, 0xe4, 0xab, 0xeb, 0x6a, 0xab,
+	0xa8, 0xb6, 0xba, 0x73, 0xc4, 0x5e, 0x8e, 0x35, 0x9b, 0x6b, 0xfc, 0x1c, 0x90, 0x7a, 0x83, 0xd6,
+	0xb3, 0x6c, 0x69, 0x68, 0xe4, 0xf7, 0x27, 0x31, 0xd2, 0x07, 0x92, 0x9a, 0x27, 0x75, 0xf7, 0x15,
+	0x00, 0x00, 0xff, 0xff, 0x75, 0x28, 0x26, 0x8f, 0x3b, 0x01, 0x00, 0x00,
 }

grpc/proto/web.proto

@@ -8,6 +8,7 @@ option go_package = "github.com/johanbrandhorst/wasm-experiments/grpc/proto/serv
 // Backend defines the interface exposed by the backend.
 service Backend {
     rpc GetUser(GetUserRequest) returns (User) {}
+    rpc GetUsers(GetUsersRequest) returns (stream User) {}
 }
 
 message GetUserRequest {
@@ -17,3 +18,7 @@ message GetUserRequest {
 message User {
     string id = 1;
 }
+
+message GetUsersRequest {
+    int64 num_users = 1;
+}