emqtt编译及简单测试记录

emqtt：在Erlang中实现的MQTT客户端库和命令行工具，支持MQTT v5.0 / 3.1.1 / 3.1。

下载源码

git clone https://github.com/emqx/emqtt.git

编译

cd emqtt & make

运行

./rebar3 shell

测试

1、初始化

{ok, ConnPid} = emqtt:start_link([{clientid, "2020"},{keepalive, 0},{proto_ver, v5},{host,"localhost"},{port,1883},{username,"SummerGao"},{password,"123456"}]).

2、建立连接

{ok, _Props} = emqtt:connect(ConnPid).

3、订阅

SubOpts = [{qos, 1}].
{ok, _Props, _ReasonCodes} = emqtt:subscribe(ConnPid, #{}, [{<<"hello">>, SubOpts}]).

①订阅主题：hello

②用MQTTBox向hello主题推送几条消息：

③flush() 一下查看接收到的消息：

 flush().

4、发布

ok = emqtt:publish(ConnPid, <<"hello">>, #{}, <<"Hello World!">>, [{qos, 0}]).

发布后，在MQTTBox订阅后可收到推送的消息

5、取消订阅

{ok, _Props, _ReasonCode} = emqtt:unsubscribe(ConnPid, #{}, <<"hello">>).

6、关闭连接

ok = emqtt:disconnect(ConnPid).

7、退出

ok = emqtt:stop(ConnPid).

测试问题

• 长时间连接断开：

** exception exit: {shutdown,nxdomain}

备注

​{ok, ConnPid} = emqtt:start_link([{clientid, "2020-01-18"}, {owner, self()}, {clean_start, true}, {proto_ver, v5}, {force_ping, true}, {keepalive, 0}, {host, "localhost"}, {port, 1883}, {username, "SummerGao"}, {password, "123456"}]).

工具

https://mqttx.app/

参考

https://github.com/emqx/emqtt