测试 Kamailio 的 evapi 模块

...
loadmodule "evapi.so"

modparam("evapi", "netstring_format", 1)
modparam("evapi", "bind_addr", "0.0.0.0:9000")
...

event_route[evapi:connection-new] {
    xlog("new connection from $evapi(srcaddr):$evapi(srcport)\n");
}
 
event_route[evapi:message-received] {
    xlog("received [$evapi(msg)] from $evapi(srcaddr):$evapi(srcport)\n");
}

启动 kamailio

运行下面的命令：

echo '13:Hello, 世界,' | nc 127.0.0.1 9000 -w 1

kamailio 日志为：

<script>: new connection from 127.0.0.1:55392

<script>: received [Hello, 世界] from 127.0.0.1:55392

evapi [evapi_dispatch.c:510]: evapi_recv_client(): client closing connection - pos [0] addr [127.0.0.1:55392]

---

netstring 的拼接规则是 {字节长度}:{原字符串},

其中字符串 "Hello, 世界" 前7个是英文字符，每个英文字符占一个字节

后2个是中文UTF8，每个中文占3个字节，一共是6字节

7+6=13

netstring 最后的结果就是 '13:Hello, 世界,'

下面是 c# 代码：

string text = "Hello, 世界"; 
byte[] data = Encoding.UTF8.GetBytes(text);
string netstring = $"{data.Length}:{text},";

需要留意的是，string 处理成了 byte 数组, 而不是 char 数组

你 get 到了吗？

全文完