Restore Unix socket support

cmd/grpcurl/grpcurl.go

@@ -363,9 +363,6 @@ func main() {
 	if *format != "json" && *format != "text" {
 		fail(nil, "The -format option must be 'json' or 'text'.")
 	}
-	if isUnixSocket != nil && isUnixSocket() {
-		fail(nil, "The -unix option is deprecated, please use unix://{path} as the address instead.")
-	}
 	if *emitDefaults && *format != "json" {
 		warn("The -emit-defaults is only used when using json format.")
 	}
@@ -486,6 +483,13 @@ func main() {
 		if *maxMsgSz > 0 {
 			opts = append(opts, grpc.WithDefaultCallOptions(grpc.MaxCallRecvMsgSize(*maxMsgSz)))
 		}
+		if isUnixSocket != nil && isUnixSocket() && !strings.HasPrefix(target, "unix://") {
+			// prepend unix:// to the address if it's not already there
+			// this is to maintain backwards compatibility because the custom dialer is replaced by
+			// the default dialer in grpc-go.
+			// https://github.com/fullstorydev/grpcurl/pull/480
+			target = "unix://" + target
+		}
 		var creds credentials.TransportCredentials
 		if *plaintext {
 			if *authority != "" {
@@ -552,7 +556,7 @@ func main() {
 
 		blockingDialTiming := dialTiming.Child("BlockingDial")
 		defer blockingDialTiming.Done()
-		cc, err := grpcurl.BlockingDial(ctx, target, creds, opts...)
+		cc, err := grpcurl.BlockingDial(ctx, "", target, creds, opts...)
 		if err != nil {
 			fail(err, "Failed to dial target host %q", target)
 		}
@@ -877,7 +881,8 @@ 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, the address must start with schema "unix://" followed by the path.
+Unix variants, if a -unix=true flag is present, then the address must be the
+path to the domain socket.
 
 Available flags:
 `, os.Args[0])

grpcurl.go

@@ -609,7 +609,9 @@ 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) {
+// The network parameter should be left empty in most cases when your address is a RFC 3986
+// compliant URI. The resolver from grpc-go will resolve the correct network type.
+func BlockingDial(ctx context.Context, network, address string, creds credentials.TransportCredentials, opts ...grpc.DialOption) (*grpc.ClientConn, error) {
 	if creds == nil {
 		creds = insecure.NewCredentials()
 	}
@@ -645,6 +647,34 @@ func BlockingDial(ctx context.Context, address string, creds credentials.Transpo
 		writeResult:          writeResult,
 	}
 
+	switch network {
+	case "":
+		// no-op, use address as-is
+	case "tcp":
+		if strings.HasPrefix(address, "unix://") {
+			return nil, fmt.Errorf("tcp network type cannot use unix address %s", address)
+		}
+	case "unix":
+		if !strings.HasPrefix(address, "unix://") {
+			// prepend unix:// to the address if it's not already there
+			// this is to maintain backwards compatibility because the custom dialer is replaced by
+			// the default dialer in grpc-go.
+			// https://github.com/fullstorydev/grpcurl/pull/480
+			address = "unix://" + address
+		}
+	default:
+		// custom dialer for other networks
+		dialer := func(ctx context.Context, address string) (net.Conn, error) {
+			conn, err := (&net.Dialer{}).DialContext(ctx, network, address)
+			if err != nil {
+				// capture the error so we can provide a better message
+				writeResult(err)
+			}
+			return conn, err
+		}
+		opts = append([]grpc.DialOption{grpc.WithContextDialer(dialer)}, opts...)
+	}
+
 	// Even with grpc.FailOnNonTempDialError, this call will usually timeout in
 	// the face of TLS handshake errors. So we can't rely on grpc.WithBlock() to
 	// know when we're done. So we run it in a goroutine and then use result

tls_settings_test.go

@@ -333,7 +333,7 @@ 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
 	}