Add grpc transport

cmd/cmd.go

@@ -33,6 +33,7 @@ import (
 
 	// transports
 	"github.com/micro/go-micro/transport"
+	tgrpc "github.com/micro/go-micro/transport/grpc"
 	thttp "github.com/micro/go-micro/transport/http"
 	tmem "github.com/micro/go-micro/transport/memory"
 )
@@ -197,6 +198,7 @@ var (
 	DefaultTransports = map[string]func(...transport.Option) transport.Transport{
 		"memory": tmem.NewTransport,
 		"http":   thttp.NewTransport,
+		"grpc":   tgrpc.NewTransport,
 	}
 
 	// used for default selection as the fall back

transport/grpc/grpc.go

@@ -0,0 +1,176 @@
+// Package grpc provides a grpc transport
+package grpc
+
+import (
+	"context"
+	"crypto/tls"
+	"net"
+
+	"github.com/micro/go-micro/transport"
+	maddr "github.com/micro/util/go/lib/addr"
+	mnet "github.com/micro/util/go/lib/net"
+	mls "github.com/micro/util/go/lib/tls"
+
+	"google.golang.org/grpc"
+	"google.golang.org/grpc/credentials"
+
+	pb "github.com/micro/go-plugins/transport/grpc/proto"
+)
+
+type grpcTransport struct {
+	opts transport.Options
+}
+
+type grpcTransportListener struct {
+	listener net.Listener
+	secure   bool
+	tls      *tls.Config
+}
+
+func getTLSConfig(addr string) (*tls.Config, error) {
+	hosts := []string{addr}
+
+	// check if its a valid host:port
+	if host, _, err := net.SplitHostPort(addr); err == nil {
+		if len(host) == 0 {
+			hosts = maddr.IPs()
+		} else {
+			hosts = []string{host}
+		}
+	}
+
+	// generate a certificate
+	cert, err := mls.Certificate(hosts...)
+	if err != nil {
+		return nil, err
+	}
+
+	return &tls.Config{Certificates: []tls.Certificate{cert}}, nil
+}
+
+func (t *grpcTransportListener) Addr() string {
+	return t.listener.Addr().String()
+}
+
+func (t *grpcTransportListener) Close() error {
+	return t.listener.Close()
+}
+
+func (t *grpcTransportListener) Accept(fn func(transport.Socket)) error {
+	var opts []grpc.ServerOption
+
+	// setup tls if specified
+	if t.secure || t.tls != nil {
+		config := t.tls
+		if config == nil {
+			var err error
+			addr := t.listener.Addr().String()
+			config, err = getTLSConfig(addr)
+			if err != nil {
+				return err
+			}
+		}
+
+		creds := credentials.NewTLS(config)
+		opts = append(opts, grpc.Creds(creds))
+	}
+
+	// new service
+	srv := grpc.NewServer(opts...)
+
+	// register service
+	pb.RegisterTransportServer(srv, &microTransport{addr: t.listener.Addr().String(), fn: fn})
+
+	// start serving
+	return srv.Serve(t.listener)
+}
+
+func (t *grpcTransport) Dial(addr string, opts ...transport.DialOption) (transport.Client, error) {
+	dopts := transport.DialOptions{
+		Timeout: transport.DefaultDialTimeout,
+	}
+
+	for _, opt := range opts {
+		opt(&dopts)
+	}
+
+	options := []grpc.DialOption{
+		grpc.WithTimeout(dopts.Timeout),
+	}
+
+	if t.opts.Secure || t.opts.TLSConfig != nil {
+		config := t.opts.TLSConfig
+		if config == nil {
+			config = &tls.Config{
+				InsecureSkipVerify: true,
+			}
+		}
+		creds := credentials.NewTLS(config)
+		options = append(options, grpc.WithTransportCredentials(creds))
+	} else {
+		options = append(options, grpc.WithInsecure())
+	}
+
+	// dial the server
+	conn, err := grpc.Dial(addr, options...)
+	if err != nil {
+		return nil, err
+	}
+
+	// create stream
+	stream, err := pb.NewTransportClient(conn).Stream(context.Background())
+	if err != nil {
+		return nil, err
+	}
+
+	// return a client
+	return &grpcTransportClient{
+		conn:   conn,
+		stream: stream,
+		local:  "localhost",
+		remote: addr,
+	}, nil
+}
+
+func (t *grpcTransport) Listen(addr string, opts ...transport.ListenOption) (transport.Listener, error) {
+	var options transport.ListenOptions
+	for _, o := range opts {
+		o(&options)
+	}
+
+	ln, err := mnet.Listen(addr, func(addr string) (net.Listener, error) {
+		return net.Listen("tcp", addr)
+	})
+	if err != nil {
+		return nil, err
+	}
+
+	return &grpcTransportListener{
+		listener: ln,
+		tls:      t.opts.TLSConfig,
+		secure:   t.opts.Secure,
+	}, nil
+}
+
+func (t *grpcTransport) Init(opts ...transport.Option) error {
+	for _, o := range opts {
+		o(&t.opts)
+	}
+	return nil
+}
+
+func (t *grpcTransport) Options() transport.Options {
+	return t.opts
+}
+
+func (t *grpcTransport) String() string {
+	return "grpc"
+}
+
+func NewTransport(opts ...transport.Option) transport.Transport {
+	var options transport.Options
+	for _, o := range opts {
+		o(&options)
+	}
+	return &grpcTransport{opts: options}
+}

transport/grpc/grpc_test.go

@@ -0,0 +1,109 @@
+package grpc
+
+import (
+	"strings"
+	"testing"
+
+	"github.com/micro/go-micro/transport"
+)
+
+func expectedPort(t *testing.T, expected string, lsn transport.Listener) {
+	parts := strings.Split(lsn.Addr(), ":")
+	port := parts[len(parts)-1]
+
+	if port != expected {
+		lsn.Close()
+		t.Errorf("Expected address to be `%s`, got `%s`", expected, port)
+	}
+}
+
+func TestGRPCTransportPortRange(t *testing.T) {
+	tp := NewTransport()
+
+	lsn1, err := tp.Listen(":44444-44448")
+	if err != nil {
+		t.Errorf("Did not expect an error, got %s", err)
+	}
+	expectedPort(t, "44444", lsn1)
+
+	lsn2, err := tp.Listen(":44444-44448")
+	if err != nil {
+		t.Errorf("Did not expect an error, got %s", err)
+	}
+	expectedPort(t, "44445", lsn2)
+
+	lsn, err := tp.Listen(":0")
+	if err != nil {
+		t.Errorf("Did not expect an error, got %s", err)
+	}
+
+	lsn.Close()
+	lsn1.Close()
+	lsn2.Close()
+}
+
+func TestGRPCTransportCommunication(t *testing.T) {
+	tr := NewTransport()
+
+	l, err := tr.Listen(":0")
+	if err != nil {
+		t.Errorf("Unexpected listen err: %v", err)
+	}
+	defer l.Close()
+
+	fn := func(sock transport.Socket) {
+		defer sock.Close()
+
+		for {
+			var m transport.Message
+			if err := sock.Recv(&m); err != nil {
+				return
+			}
+
+			if err := sock.Send(&m); err != nil {
+				return
+			}
+		}
+	}
+
+	done := make(chan bool)
+
+	go func() {
+		if err := l.Accept(fn); err != nil {
+			select {
+			case <-done:
+			default:
+				t.Errorf("Unexpected accept err: %v", err)
+			}
+		}
+	}()
+
+	c, err := tr.Dial(l.Addr())
+	if err != nil {
+		t.Errorf("Unexpected dial err: %v", err)
+	}
+	defer c.Close()
+
+	m := transport.Message{
+		Header: map[string]string{
+			"X-Content-Type": "application/json",
+		},
+		Body: []byte(`{"message": "Hello World"}`),
+	}
+
+	if err := c.Send(&m); err != nil {
+		t.Errorf("Unexpected send err: %v", err)
+	}
+
+	var rm transport.Message
+
+	if err := c.Recv(&rm); err != nil {
+		t.Errorf("Unexpected recv err: %v", err)
+	}
+
+	if string(rm.Body) != string(m.Body) {
+		t.Errorf("Expected %v, got %v", m.Body, rm.Body)
+	}
+
+	close(done)
+}

transport/grpc/handler.go

@@ -0,0 +1,39 @@
+package grpc
+
+import (
+	"runtime/debug"
+
+	"github.com/micro/go-log"
+	"github.com/micro/go-micro/transport"
+	pb "github.com/micro/go-plugins/transport/grpc/proto"
+	"google.golang.org/grpc/peer"
+)
+
+// microTransport satisfies the pb.TransportServer inteface
+type microTransport struct {
+	addr string
+	fn   func(transport.Socket)
+}
+
+func (m *microTransport) Stream(ts pb.Transport_StreamServer) error {
+	sock := &grpcTransportSocket{
+		stream: ts,
+		local:  m.addr,
+	}
+
+	p, ok := peer.FromContext(ts.Context())
+	if ok {
+		sock.remote = p.Addr.String()
+	}
+
+	defer func() {
+		if r := recover(); r != nil {
+			log.Log(r, string(debug.Stack()))
+			sock.Close()
+		}
+	}()
+
+	// execute socket func
+	m.fn(sock)
+	return nil
+}