Update godeps

vendor/google.golang.org/grpc/transport/transport.go

@@ -44,7 +44,6 @@ import (
 	"io"
 	"net"
 	"sync"
-	"time"
 
 	"golang.org/x/net/context"
 	"golang.org/x/net/trace"
@@ -120,10 +119,11 @@ func (b *recvBuffer) get() <-chan item {
 // recvBufferReader implements io.Reader interface to read the data from
 // recvBuffer.
 type recvBufferReader struct {
-	ctx  context.Context
-	recv *recvBuffer
-	last *bytes.Reader // Stores the remaining data in the previous calls.
-	err  error
+	ctx    context.Context
+	goAway chan struct{}
+	recv   *recvBuffer
+	last   *bytes.Reader // Stores the remaining data in the previous calls.
+	err    error
 }
 
 // Read reads the next len(p) bytes from last. If last is drained, it tries to
@@ -141,6 +141,8 @@ func (r *recvBufferReader) Read(p []byte) (n int, err error) {
 	select {
 	case <-r.ctx.Done():
 		return 0, ContextErr(r.ctx.Err())
+	case <-r.goAway:
+		return 0, ErrStreamDrain
 	case i := <-r.recv.get():
 		r.recv.load()
 		m := i.(*recvMsg)
@@ -158,7 +160,7 @@ const (
 	streamActive    streamState = iota
 	streamWriteDone             // EndStream sent
 	streamReadDone              // EndStream received
-	streamDone                  // sendDone and recvDone or RSTStreamFrame is sent or received.
+	streamDone                  // the entire stream is finished.
 )
 
 // Stream represents an RPC in the transport layer.
@@ -169,6 +171,10 @@ type Stream struct {
 	// ctx is the associated context of the stream.
 	ctx    context.Context
 	cancel context.CancelFunc
+	// done is closed when the final status arrives.
+	done chan struct{}
+	// goAway is closed when the server sent GoAways signal before this stream was initiated.
+	goAway chan struct{}
 	// method records the associated RPC method of the stream.
 	method       string
 	recvCompress string
@@ -214,6 +220,18 @@ func (s *Stream) SetSendCompress(str string) {
 	s.sendCompress = str
 }
 
+// Done returns a chanel which is closed when it receives the final status
+// from the server.
+func (s *Stream) Done() <-chan struct{} {
+	return s.done
+}
+
+// GoAway returns a channel which is closed when the server sent GoAways signal
+// before this stream was initiated.
+func (s *Stream) GoAway() <-chan struct{} {
+	return s.goAway
+}
+
 // Header acquires the key-value pairs of header metadata once it
 // is available. It blocks until i) the metadata is ready or ii) there is no
 // header metadata or iii) the stream is cancelled/expired.
@@ -221,6 +239,8 @@ func (s *Stream) Header() (metadata.MD, error) {
 	select {
 	case <-s.ctx.Done():
 		return nil, ContextErr(s.ctx.Err())
+	case <-s.goAway:
+		return nil, ErrStreamDrain
 	case <-s.headerChan:
 		return s.header.Copy(), nil
 	}
@@ -335,19 +355,17 @@ type ConnectOptions struct {
 	// UserAgent is the application user agent.
 	UserAgent string
 	// Dialer specifies how to dial a network address.
-	Dialer func(string, time.Duration) (net.Conn, error)
+	Dialer func(context.Context, string) (net.Conn, error)
 	// PerRPCCredentials stores the PerRPCCredentials required to issue RPCs.
 	PerRPCCredentials []credentials.PerRPCCredentials
 	// TransportCredentials stores the Authenticator required to setup a client connection.
 	TransportCredentials credentials.TransportCredentials
-	// Timeout specifies the timeout for dialing a ClientTransport.
-	Timeout time.Duration
 }
 
 // NewClientTransport establishes the transport with the required ConnectOptions
 // and returns it to the caller.
-func NewClientTransport(target string, opts *ConnectOptions) (ClientTransport, error) {
-	return newHTTP2Client(target, opts)
+func NewClientTransport(ctx context.Context, target string, opts ConnectOptions) (ClientTransport, error) {
+	return newHTTP2Client(ctx, target, opts)
 }
 
 // Options provides additional hints and information for message
@@ -417,6 +435,11 @@ type ClientTransport interface {
 	// and create a new one) in error case. It should not return nil
 	// once the transport is initiated.
 	Error() <-chan struct{}
+
+	// GoAway returns a channel that is closed when ClientTranspor
+	// receives the draining signal from the server (e.g., GOAWAY frame in
+	// HTTP/2).
+	GoAway() <-chan struct{}
 }
 
 // ServerTransport is the common interface for all gRPC server-side transport
@@ -448,6 +471,9 @@ type ServerTransport interface {
 
 	// RemoteAddr returns the remote network address.
 	RemoteAddr() net.Addr
+
+	// Drain notifies the client this ServerTransport stops accepting new RPCs.
+	Drain()
 }
 
 // StreamErrorf creates an StreamError with the specified error code and description.
@@ -459,9 +485,11 @@ func StreamErrorf(c codes.Code, format string, a ...interface{}) StreamError {
 }
 
 // ConnectionErrorf creates an ConnectionError with the specified error description.
-func ConnectionErrorf(format string, a ...interface{}) ConnectionError {
+func ConnectionErrorf(temp bool, e error, format string, a ...interface{}) ConnectionError {
 	return ConnectionError{
 		Desc: fmt.Sprintf(format, a...),
+		temp: temp,
+		err:  e,
 	}
 }
 
@@ -469,14 +497,36 @@ func ConnectionErrorf(format string, a ...interface{}) ConnectionError {
 // entire connection and the retry of all the active streams.
 type ConnectionError struct {
 	Desc string
+	temp bool
+	err  error
 }
 
 func (e ConnectionError) Error() string {
 	return fmt.Sprintf("connection error: desc = %q", e.Desc)
 }
 
-// ErrConnClosing indicates that the transport is closing.
-var ErrConnClosing = ConnectionError{Desc: "transport is closing"}
+// Temporary indicates if this connection error is temporary or fatal.
+func (e ConnectionError) Temporary() bool {
+	return e.temp
+}
+
+// Origin returns the original error of this connection error.
+func (e ConnectionError) Origin() error {
+	// Never return nil error here.
+	// If the original error is nil, return itself.
+	if e.err == nil {
+		return e
+	}
+	return e.err
+}
+
+var (
+	// ErrConnClosing indicates that the transport is closing.
+	ErrConnClosing = ConnectionError{Desc: "transport is closing", temp: true}
+	// ErrStreamDrain indicates that the stream is rejected by the server because
+	// the server stops accepting new RPCs.
+	ErrStreamDrain = StreamErrorf(codes.Unavailable, "the server stops accepting new RPCs")
+)
 
 // StreamError is an error that only affects one stream within a connection.
 type StreamError struct {
@@ -501,12 +551,25 @@ func ContextErr(err error) StreamError {
 
 // wait blocks until it can receive from ctx.Done, closing, or proceed.
 // If it receives from ctx.Done, it returns 0, the StreamError for ctx.Err.
+// If it receives from done, it returns 0, io.EOF if ctx is not done; otherwise
+// it return the StreamError for ctx.Err.
+// If it receives from goAway, it returns 0, ErrStreamDrain.
 // If it receives from closing, it returns 0, ErrConnClosing.
 // If it receives from proceed, it returns the received integer, nil.
-func wait(ctx context.Context, closing <-chan struct{}, proceed <-chan int) (int, error) {
+func wait(ctx context.Context, done, goAway, closing <-chan struct{}, proceed <-chan int) (int, error) {
 	select {
 	case <-ctx.Done():
 		return 0, ContextErr(ctx.Err())
+	case <-done:
+		// User cancellation has precedence.
+		select {
+		case <-ctx.Done():
+			return 0, ContextErr(ctx.Err())
+		default:
+		}
+		return 0, io.EOF
+	case <-goAway:
+		return 0, ErrStreamDrain
 	case <-closing:
 		return 0, ErrConnClosing
 	case i := <-proceed: