freeswitch笔记(9)-esl outbound中如何放音采集按键？
关于这个功能，esl-client 上给出的源码示例极具误导性，根本跑不起来，见： https://github.com/esl-client/esl-client/blob/master/src/test/java/OutboundTest.java
正确姿势：必须在事件订阅的回调里，才能拿到用户按键值
示例代码：
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
|
package org.freeswitch.esl.client;import org.freeswitch.esl.client.dptools.Execute;import org.freeswitch.esl.client.dptools.ExecuteException;import org.freeswitch.esl.client.internal.Context;import org.freeswitch.esl.client.outbound.IClientHandler;import org.freeswitch.esl.client.outbound.IClientHandlerFactory;import org.freeswitch.esl.client.outbound.SocketClient;import org.freeswitch.esl.client.transport.event.EslEvent;import org.freeswitch.esl.client.transport.message.EslHeaders.Name;import org.freeswitch.esl.client.transport.message.EslMessage;import org.slf4j.Logger;import org.slf4j.LoggerFactory;import java.net.InetSocketAddress;import java.util.regex.Pattern;import static com.google.common.base.Throwables.throwIfUnchecked;public class OutboundDTMFTest { private static Logger logger = LoggerFactory.getLogger(OutboundDTMFTest.class); private static String sb = "/usr/local/freeswitch/sounds/en/us/callie/ivr/8000/"; String prompt = sb + "ivr-please_enter_extension_followed_by_pound.wav"; String failed = sb + "ivr-that_was_an_invalid_entry.wav"; public static void main(String[] args) { new OutboundDTMFTest(); } public OutboundDTMFTest() { try { //outbound test final SocketClient outboundServer = new SocketClient( new InetSocketAddress("localhost", 8086), new OutboundHandlerFactory()); outboundServer.startAsync(); } catch (Throwable t) { throwIfUnchecked(t); } } public class OutboundHandlerFactory implements IClientHandlerFactory { @Override public IClientHandler createClientHandler() { //just for sample , recommend use singleton pattern, to avoid new too many instance return new OutboundHandler(); } } public class OutboundHandler implements IClientHandler { StringBuffer buffer = new StringBuffer(10); String pattern1 = "^\\d+"; String pattern2 = "^\\d+#$"; @Override public void onConnect(Context context, EslEvent eslEvent) { try { Execute exe = new Execute(context, ""); //订阅DTMF事件 EslMessage eslMessage = context.sendCommand("event plain DTMF"); if (eslMessage.getHeaderValue(Name.REPLY_TEXT).startsWith("+OK")) { logger.info("subscribe event success!"); } exe.answer(); int timeOutSeconds = 30; //放音采集 exe.playAndGetDigits(1, 1, 10, timeOutSeconds * 1000, "#", prompt, failed, pattern1, timeOutSeconds * 1000); //等待用户输入按键 long start = System.currentTimeMillis(); while (true) { if (System.currentTimeMillis() - start > timeOutSeconds * 1000) { break; } if (buffer.length() > 0 && Pattern.matches(pattern2, buffer.toString())) { break; } Thread.sleep(50); } System.out.println("you pressed:" + buffer.toString()); } catch (ExecuteException | InterruptedException e) { logger.error("Could not prompt for digits", e); } finally { context.closeChannel(); } } @Override public void onEslEvent(Context ctx, EslEvent event) {// System.out.println(event.getEventName()); if (event.getEventName().equalsIgnoreCase("DTMF")) { String key = event.getEventHeaders().get("DTMF-Digit"); if ("#".equalsIgnoreCase(key)) { //检查是否输入正确（如果错误，请将之前输入的清空掉） if (!Pattern.matches(pattern1, buffer.toString())) { buffer.setLength(0); return; } } buffer.append(key); } } }} |
解释一下：
1. 首先要订阅DTMF事件，只有在事件回调里，才能拿到用户按键信息
2. playAndGetDigits 在outbound async full异步模式下，这个方法的返回值，其实没啥用，永远都是__undef__，所以要在后面循环检测结果，还要考虑用户一直不按键的情况，要有超时保底
3. 事件回调onEslEvent与用户进线onConnect是在2个不同的方法中，但是都是在同一个线程里的，所以为方便起见，用了一个线程安全的StringBuffer用来保存按键信息
4. 事件回调中，要考虑用户按错键的情况，比如提示用户按数字键，然后用户输入了字母或星号之类的，遇到这种要把之前的输入结果清掉。
