Update to gRPC 1.7 functions.

Changes:
- ServerTransport.Write now takes 1 header slice and 1 payload slice.
- metadata.FromContext was removed. Replace with metadata.FromIncomingContext.

test/server/main.go

@@ -125,7 +125,7 @@ func (s *testSrv) PingEmpty(ctx context.Context, _ *empty.Empty) (*testproto.Pin
 
 func (s *testSrv) Ping(ctx context.Context, ping *testproto.PingRequest) (*testproto.PingResponse, error) {
 	if ping.GetCheckMetadata() {
-		md, ok := metadata.FromContext(ctx)
+		md, ok := metadata.FromIncomingContext(ctx)
 		if !ok || len(md[strings.ToLower(shared.ClientMDTestKey)]) == 0 ||
 			md[strings.ToLower(shared.ClientMDTestKey)][0] != shared.ClientMDTestValue {
 			return nil, status.Errorf(codes.InvalidArgument, "Metadata was invalid")
@@ -174,7 +174,7 @@ func (s *testSrv) PingError(ctx context.Context, ping *testproto.PingRequest) (*
 
 func (s *testSrv) PingList(ping *testproto.PingRequest, stream testproto.TestService_PingListServer) error {
 	if ping.GetCheckMetadata() {
-		md, ok := metadata.FromContext(stream.Context())
+		md, ok := metadata.FromIncomingContext(stream.Context())
 		if !ok || len(md[strings.ToLower(shared.ClientMDTestKey)]) == 0 ||
 			md[strings.ToLower(shared.ClientMDTestKey)][0] != shared.ClientMDTestValue {
 			return status.Errorf(codes.InvalidArgument, "Metadata was invalid")
@@ -208,7 +208,7 @@ func (s *testSrv) PingList(ping *testproto.PingRequest, stream testproto.TestSer
 			if !ok {
 				return status.Errorf(codes.Internal, "lowLevelServerStream does not exist in context")
 			}
-			lowLevelServerStream.ServerTransport().Write(lowLevelServerStream, make([]byte, 0), &transport.Options{
+			lowLevelServerStream.ServerTransport().Write(lowLevelServerStream, nil, nil, &transport.Options{
 				Delay: false,
 			})
 		}

wsproxy/wsproxy.go

@@ -8,6 +8,7 @@ import (
 	"net"
 	"net/http"
 	"strings"
+	"time"
 
 	"github.com/gorilla/websocket"
 	"google.golang.org/grpc/codes"
@@ -18,6 +19,8 @@ import (
 	"github.com/johanbrandhorst/protobuf/internal"
 )
 
+const headerSize = 5
+
 // Logger is the interface used by the proxy to log events
 type Logger interface {
 	Debugln(...interface{})
@@ -115,11 +118,14 @@ func (p *proxy) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 
 	host := withPort(r.Host)
 	p.logger.Debugln("Creating new transport with addr:", host)
-	t, err := transport.NewClientTransport(ctx,
+	t, err := transport.NewClientTransport(
+		ctx,
 		transport.TargetInfo{Addr: host},
 		transport.ConnectOptions{
 			TransportCredentials: p.creds,
-		})
+		},
+		time.Second*20,
+	)
 	if err != nil {
 		closeMsg := formatCloseMessage(websocket.CloseInternalServerErr, err.Error())
 		_ = conn.WriteMessage(websocket.CloseMessage, closeMsg)
@@ -182,14 +188,14 @@ func (p *proxy) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 			}
 			p.logger.Debugln("[READ] Read payload:", payload)
 			if internal.IsCloseMessage(payload) {
-				err = t.Write(s, nil, &transport.Options{Last: true})
+				err = t.Write(s, nil, nil, &transport.Options{Last: true})
 				if err == io.EOF || err == nil {
 					// Do not want to cancel context here, want
 					// Writer to read io.EOF then exit.
 					return
 				}
 			} else {
-				err = t.Write(s, payload, &transport.Options{Last: false})
+				err = t.Write(s, payload[:headerSize], payload[headerSize:], &transport.Options{Last: false})
 			}
 
 			if err != nil {
@@ -204,7 +210,7 @@ func (p *proxy) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	}()
 
 	// Write loop -- take messages from stream and write to websocket
-	var header [5]byte
+	var header [headerSize]byte
 	var msg []byte
 	for {
 		// Read header