support unix sockets (#26)

cmd/grpcurl/grpcurl.go

@@ -33,6 +33,8 @@ import (
 var (
 	exit = os.Exit
 
+	isUnixSocket func() bool // nil when run on non-unix platform
+
 	help = flag.Bool("help", false,
 		`Print usage instructions and exit.`)
 	plaintext = flag.Bool("plaintext", false,
@@ -240,7 +242,11 @@ func main() {
 				}
 			}
 		}
-		cc, err := grpcurl.BlockingDial(ctx, target, creds, opts...)
+		network := "tcp"
+		if isUnixSocket != nil && isUnixSocket() {
+			network = "unix"
+		}
+		cc, err := grpcurl.BlockingDial(ctx, network, target, creds, opts...)
 		if err != nil {
 			fail(err, "Failed to dial target host %q", target)
 		}
@@ -407,7 +413,7 @@ func main() {
 
 func usage() {
 	fmt.Fprintf(os.Stderr, `Usage:
-	%s [flags] [host:port] [list|describe] [symbol]
+	%s [flags] [address] [list|describe] [symbol]
 
 The 'host:port' is only optional when used with 'list' or 'describe' and a
 protoset flag is provided.
@@ -425,6 +431,11 @@ If neither verb is present, the symbol must be a fully-qualified method name in
 be used to invoke the named method. If no body is given, an empty instance of
 the method's request type will be sent.
 
+The address will typically be in the form "host:port" where host can be an IP
+address or a hostname and port is a numeric port or service name. If an IPv6
+address is given, it must be surrounded by brackets, like "[2001:db8::1]". For
+Unix variants, if a -unix=true flag is present, then the address must be the
+path to the domain socket.
 `, os.Args[0])
 	flag.PrintDefaults()
 

cmd/grpcurl/unix.go

@@ -0,0 +1,16 @@
+// +build darwin dragonfly freebsd linux netbsd openbsd solaris
+
+package main
+
+import "flag"
+
+var (
+	unix = flag.Bool("unix", false,
+		`Indicates that the server address is the path to a Unix domain socket.`)
+)
+
+func init() {
+	isUnixSocket = func() bool {
+		return *unix
+	}
+}

cmd/testserver/testserver.go

@@ -23,19 +23,21 @@ import (
 )
 
 var (
+	getUnixSocket func() string // nil when run on non-unix platforms
+
 	help   = flag.Bool("help", false, "Print usage instructions and exit.")
 	cacert = flag.String("cacert", "",
-		"File containing trusted root certificates for verifying  client certs. Ignored if\n"+
-			"    	TLS is not in use (e.g. no -cert or -key specified).")
+		`File containing trusted root certificates for verifying  client certs. Ignored
+    	if TLS is not in use (e.g. no -cert or -key specified).`)
 	cert = flag.String("cert", "",
-		"File containing server certificate (public key). Must also provide -key option.\n"+
-			"    	Server uses plain-text if no -cert and -key options are given.")
+		`File containing server certificate (public key). Must also provide -key option.
+    	Server uses plain-text if no -cert and -key options are given.`)
 	key = flag.String("key", "",
-		"File containing server private key. Must also provide -cert option. Server uses\n"+
-			"    	plain-text if no -cert and -key options are given.")
+		`File containing server private key. Must also provide -cert option. Server uses
+    	plain-text if no -cert and -key options are given.`)
 	requirecert = flag.Bool("requirecert", false,
-		"Require clients to authenticate via client certs. Must be using TLS (e.g. must also\n"+
-			"    	provide -cert and -key options).")
+		`Require clients to authenticate via client certs. Must be using TLS (e.g. must
+    	also provide -cert and -key options).`)
 	port      = flag.Int("p", 0, "Port on which to listen. Ephemeral port used if not specified.")
 	noreflect = flag.Bool("noreflect", false, "Indicates that server should not support server reflection.")
 	quiet     = flag.Bool("q", false, "Suppresses server request and stream logging.")
@@ -77,13 +79,20 @@ func main() {
 		opts = append(opts, grpc.UnaryInterceptor(unaryLogger), grpc.StreamInterceptor(streamLogger))
 	}
 
-	l, err := net.Listen("tcp", fmt.Sprintf("127.0.0.1:%d", *port))
+	var network, addr string
+	if getUnixSocket != nil && getUnixSocket() != "" {
+		network = "unix"
+		addr = getUnixSocket()
+	} else {
+		network = "tcp"
+		addr = fmt.Sprintf("127.0.0.1:%d", *port)
+	}
+	l, err := net.Listen(network, addr)
 	if err != nil {
 		fmt.Fprintf(os.Stderr, "Failed to listen on socket: %v\n", err)
 		os.Exit(1)
 	}
-	p := l.Addr().(*net.TCPAddr).Port
-	fmt.Printf("Listening on 127.0.0.1:%d\n", p)
+	fmt.Printf("Listening on %v\n", l.Addr())
 
 	svr := grpc.NewServer(opts...)
 

cmd/testserver/unix.go

@@ -0,0 +1,17 @@
+// +build darwin dragonfly freebsd linux netbsd openbsd solaris
+
+package main
+
+import "flag"
+
+var (
+	unix = flag.String("unix", "",
+		`Use instead of -p to indicate listening on a Unix domain socket instead of a
+    	TCP port. If present, must be the path to a domain socket.`)
+)
+
+func init() {
+	getUnixSocket = func() string {
+		return *unix
+	}
+}

grpcurl.go

@@ -878,7 +878,7 @@ func ServerTransportCredentials(cacertFile, serverCertFile, serverKeyFile string
 // BlockingDial is a helper method to dial the given address, using optional TLS credentials,
 // and blocking until the returned connection is ready. If the given credentials are nil, the
 // connection will be insecure (plain-text).
-func BlockingDial(ctx context.Context, address string, creds credentials.TransportCredentials, opts ...grpc.DialOption) (*grpc.ClientConn, error) {
+func BlockingDial(ctx context.Context, network, address string, creds credentials.TransportCredentials, opts ...grpc.DialOption) (*grpc.ClientConn, error) {
 	// grpc.Dial doesn't provide any information on permanent connection errors (like
 	// TLS handshake failures). So in order to provide good error messages, we need a
 	// custom dialer that can provide that info. That means we manage the TLS handshake.
@@ -895,7 +895,8 @@ func BlockingDial(ctx context.Context, address string, creds credentials.Transpo
 	dialer := func(address string, timeout time.Duration) (net.Conn, error) {
 		ctx, cancel := context.WithTimeout(ctx, timeout)
 		defer cancel()
-		conn, err := (&net.Dialer{Cancel: ctx.Done()}).Dial("tcp", address)
+
+		conn, err := (&net.Dialer{Cancel: ctx.Done()}).Dial(network, address)
 		if err != nil {
 			writeResult(err)
 			return nil, err

tls_settings_test.go

@@ -316,7 +316,7 @@ func createTestServerAndClient(serverCreds, clientCreds credentials.TransportCre
 	ctx, cancel := context.WithTimeout(context.Background(), 3*time.Second)
 	defer cancel()
 
-	cc, err := BlockingDial(ctx, fmt.Sprintf("127.0.0.1:%d", port), clientCreds)
+	cc, err := BlockingDial(ctx, "tcp", fmt.Sprintf("127.0.0.1:%d", port), clientCreds)
 	if err != nil {
 		return e, err
 	}