Merge pull request #27061 from Luap99/bindings-upgrade

pkg/bindings: use HTTP 101 upgrade request for attach

pkg/bindings/containers/attach.go

@@ -111,37 +111,11 @@ func Attach(ctx context.Context, nameOrID string, stdin io.Reader, stdout io.Wri
 		}()
 	}
 
-	headers := make(http.Header)
-	headers.Add("Connection", "Upgrade")
-	headers.Add("Upgrade", "tcp")
-
-	var socket net.Conn
-	socketSet := false
-	dialContext := conn.Client.Transport.(*http.Transport).DialContext
-	t := &http.Transport{
-		DialContext: func(ctx context.Context, network, address string) (net.Conn, error) {
-			c, err := dialContext(ctx, network, address)
-			if err != nil {
-				return nil, err
-			}
-			if !socketSet {
-				socket = c
-				socketSet = true
-			}
-			return c, err
-		},
-		IdleConnTimeout: time.Duration(0),
-	}
-	conn.Client.Transport = t
-	response, err := conn.DoRequest(ctx, nil, http.MethodPost, "/containers/%s/attach", params, headers, nameOrID)
+	cw, socket, err := newUpgradeRequest(ctx, conn, nil, fmt.Sprintf("/containers/%s/attach", nameOrID), params)
 	if err != nil {
 		return err
 	}
-
-	if !response.IsSuccess() && !response.IsInformational() {
-		defer response.Body.Close()
-		return response.Process(nil)
-	}
+	defer socket.Close()
 
 	if needTTY {
 		winChange := make(chan os.Signal, 1)
@@ -173,11 +147,7 @@ func Attach(ctx context.Context, nameOrID string, stdin io.Reader, stdout io.Wri
 				logrus.Errorf("Failed to write input to service: %v", err)
 			}
 			if err == nil {
-				if closeWrite, ok := socket.(CloseWriter); ok {
-					if err := closeWrite.CloseWrite(); err != nil {
-						logrus.Warnf("Failed to close STDIN for writing: %v", err)
-					}
-				}
+				cw.CloseWrite()
 			}
 			stdinChan <- err
 		}()
@@ -210,7 +180,7 @@ func Attach(ctx context.Context, nameOrID string, stdin io.Reader, stdout io.Wri
 					return err
 				}
 
-				return nil
+				return <-stdoutChan
 			}
 		}
 	} else {
@@ -464,33 +434,11 @@ func ExecStartAndAttach(ctx context.Context, sessionID string, options *ExecStar
 		return err
 	}
 
-	var socket net.Conn
-	socketSet := false
-	dialContext := conn.Client.Transport.(*http.Transport).DialContext
-	t := &http.Transport{
-		DialContext: func(ctx context.Context, network, address string) (net.Conn, error) {
-			c, err := dialContext(ctx, network, address)
-			if err != nil {
-				return nil, err
-			}
-			if !socketSet {
-				socket = c
-				socketSet = true
-			}
-			return c, err
-		},
-		IdleConnTimeout: time.Duration(0),
-	}
-	conn.Client.Transport = t
-	response, err := conn.DoRequest(ctx, bytes.NewReader(bodyJSON), http.MethodPost, "/exec/%s/start", nil, nil, sessionID)
+	cw, socket, err := newUpgradeRequest(ctx, conn, bytes.NewReader(bodyJSON), fmt.Sprintf("/exec/%s/start", sessionID), nil)
 	if err != nil {
 		return err
 	}
-	defer response.Body.Close()
-
-	if !response.IsSuccess() && !response.IsInformational() {
-		return response.Process(nil)
-	}
+	defer socket.Close()
 
 	if needTTY {
 		winChange := make(chan os.Signal, 1)
@@ -513,12 +461,7 @@ func ExecStartAndAttach(ctx context.Context, sessionID string, options *ExecStar
 			}
 
 			if err == nil {
-				if closeWrite, ok := socket.(CloseWriter); ok {
-					logrus.Debugf("Closing STDIN")
-					if err := closeWrite.CloseWrite(); err != nil {
-						logrus.Warnf("Failed to close STDIN for writing: %v", err)
-					}
-				}
+				cw.CloseWrite()
 			}
 		}()
 	}
@@ -580,3 +523,66 @@ func ExecStartAndAttach(ctx context.Context, sessionID string, options *ExecStar
 	}
 	return nil
 }
+
+type closeWrite struct {
+	// sock is the underlying socket of the connection.
+	// Do not use that field directly.
+	sock net.Conn
+}
+
+func (cw *closeWrite) CloseWrite() {
+	if closeWrite, ok := cw.sock.(CloseWriter); ok {
+		logrus.Debugf("Closing STDIN")
+		if err := closeWrite.CloseWrite(); err != nil {
+			logrus.Warnf("Failed to close STDIN for writing: %v", err)
+		}
+	}
+}
+
+// newUpgradeRequest performs a new http Upgrade request, it return the closeWrite which should be used
+// to close the STDIN side used and the ReadWriter which MUST be uses to write/read from the connection
+// and which must closed when finished. Do not access the new.Conn in closeWrite directly.
+func newUpgradeRequest(ctx context.Context, conn *bindings.Connection, body io.Reader, path string, params url.Values) (*closeWrite, io.ReadWriteCloser, error) {
+	headers := http.Header{
+		"Connection": []string{"Upgrade"},
+		"Upgrade":    []string{"tcp"},
+	}
+
+	var socket net.Conn
+	socketSet := false
+	dialContext := conn.Client.Transport.(*http.Transport).DialContext
+	t := &http.Transport{
+		DialContext: func(ctx context.Context, network, address string) (net.Conn, error) {
+			c, err := dialContext(ctx, network, address)
+			if err != nil {
+				return nil, err
+			}
+			if !socketSet {
+				socket = c
+				socketSet = true
+			}
+			return c, err
+		},
+		IdleConnTimeout: time.Duration(0),
+	}
+	conn.Client.Transport = t
+	response, err := conn.DoRequest(ctx, body, http.MethodPost, path, params, headers)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	if response.StatusCode != http.StatusSwitchingProtocols {
+		defer response.Body.Close()
+		if err := response.Process(nil); err != nil {
+			return nil, nil, err
+		}
+		return nil, nil, fmt.Errorf("incorrect server response code %d, expected %d", response.StatusCode, http.StatusSwitchingProtocols)
+	}
+	rw, ok := response.Body.(io.ReadWriteCloser)
+	if !ok {
+		response.Body.Close()
+		return nil, nil, errors.New("internal error: cannot cast to http response Body to io.ReadWriteCloser")
+	}
+
+	return &closeWrite{sock: socket}, rw, nil
+}