1/*
2 * Copyright (C) 2014 Square, Inc.
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16package com.squareup.okhttp.ws;
17
18import com.squareup.okhttp.Response;
19import com.squareup.okhttp.ResponseBody;
20import java.io.IOException;
21import okio.Buffer;
22
23/** Listener for server-initiated messages on a connected {@link WebSocket}. */
24public interface WebSocketListener {
25  /**
26   * Called when the request has successfully been upgraded to a web socket. This method is called
27   * on the message reading thread to allow setting up any state before the
28   * {@linkplain #onMessage message}, {@linkplain #onPong pong}, and {@link #onClose close}
29   * callbacks start.
30   * <p>
31   * <b>Do not</b> use this callback to write to the web socket. Start a new thread or use
32   * another thread in your application.
33   */
34  void onOpen(WebSocket webSocket, Response response);
35
36  /**
37   * Called when the transport or protocol layer of this web socket errors during communication.
38   *
39   * @param response Present when the failure is a direct result of the response (e.g., failed
40   * upgrade, non-101 response code, etc.). {@code null} otherwise.
41   */
42  void onFailure(IOException e, Response response);
43
44  /**
45   * Called when a server message is received. The {@code type} indicates whether the
46   * {@code payload} should be interpreted as UTF-8 text or binary data.
47   *
48   * <p>Implementations <strong>must</strong> call {@code source.close()} before returning. This
49   * indicates completion of parsing the message payload and will consume any remaining bytes in
50   * the message.
51   *
52   * <p>The {@linkplain ResponseBody#contentType() content type} of {@code message} will be either
53   * {@link WebSocket#TEXT} or {@link WebSocket#BINARY} which indicates the format of the message.
54   */
55  void onMessage(ResponseBody message) throws IOException;
56
57  /**
58   * Called when a server pong is received. This is usually a result of calling {@link
59   * WebSocket#sendPing(Buffer)} but might also be unsolicited.
60   */
61  void onPong(Buffer payload);
62
63  /**
64   * Called when the server sends a close message. This may have been initiated
65   * from a call to {@link WebSocket#close(int, String) close()} or as an unprompted
66   * message from the server.
67   *
68   * @param code The <a href="http://tools.ietf.org/html/rfc6455#section-7.4.1">RFC-compliant</a>
69   * status code.
70   * @param reason Reason for close or an empty string.
71   */
72  void onClose(int code, String reason);
73}
74