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.MediaType;
19import com.squareup.okhttp.RequestBody;
20import java.io.IOException;
21import okio.Buffer;
22
23/** Blocking interface to connect and write to a web socket. */
24public interface WebSocket {
25  /** A {@link MediaType} indicating UTF-8 text frames should be used when sending the message. */
26  MediaType TEXT = MediaType.parse("application/vnd.okhttp.websocket+text; charset=utf-8");
27  /** A {@link MediaType} indicating binary frames should be used when sending the message. */
28  MediaType BINARY = MediaType.parse("application/vnd.okhttp.websocket+binary");
29
30  /**
31   * Send a message payload to the server.
32   *
33   * <p>The {@linkplain RequestBody#contentType() content type} of {@code message} should be either
34   * {@link #TEXT} or {@link #BINARY}.
35   *
36   * @throws IOException if unable to write the message. Clients must call {@link #close} when this
37   * happens to ensure resources are cleaned up.
38   * @throws IllegalStateException if not connected, already closed, or another writer is active.
39   */
40  void sendMessage(RequestBody message) throws IOException;
41
42  /**
43   * Send a ping to the server with optional payload.
44   *
45   * @throws IOException if unable to write the ping.  Clients must call {@link #close} when this
46   * happens to ensure resources are cleaned up.
47   * @throws IllegalStateException if already closed.
48   */
49  void sendPing(Buffer payload) throws IOException;
50
51  /**
52   * Send a close frame to the server.
53   * <p>
54   * The corresponding {@link WebSocketListener} will continue to get messages until its
55   * {@link WebSocketListener#onClose onClose()} method is called.
56   * <p>
57   * It is an error to call this method before calling close on an active writer. Calling this
58   * method more than once has no effect.
59   *
60   * @throws IOException if unable to write the close message. Resources will still be freed.
61   * @throws IllegalStateException if already closed.
62   */
63  void close(int code, String reason) throws IOException;
64}
65