请用python编写一个MQTT收发的程序
时间: 2023-10-19 11:07:24 浏览: 41
好的,以下是一个简单的Python程序,可以实现MQTT消息的收发:
```python
import paho.mqtt.client as mqtt
# 连接MQTT服务器
client = mqtt.Client()
client.connect("broker.hivemq.com", 1883, 60)
# 发送消息
client.publish("test/topic", "Hello World!")
# 接收消息
def on_message(client, userdata, msg):
print(msg.topic + " " + str(msg.payload))
client.on_message = on_message
client.subscribe("test/topic")
# 循环接收消息
client.loop_forever()
```
这个程序首先连接到MQTT服务器(这里使用了公共的HiveMQ服务器),然后向`test/topic`主题发送一条消息。接着,程序定义了一个`on_message`回调函数,用于处理收到的消息。最后,程序通过调用`client.loop_forever()`函数开始循环接收消息。当程序接收到`test/topic`主题的消息时,`on_message`函数将被调用,打印出收到的消息。
相关问题
Python编写一个MQTT客户端链接ChatGPTapi
可以使用paho-mqtt库来编写一个MQTT客户端链接ChatGPTapi,以下是示例代码:
```python
import paho.mqtt.client as mqtt
# 定义回调函数
def on_connect(client, userdata, flags, rc):
print("Connected with result code "+str(rc))
# 订阅主题
client.subscribe("chatgpt/api")
def on_message(client, userdata, msg):
print(msg.topic+" "+str(msg.payload))
# 创建MQTT客户端
client = mqtt.Client()
# 设置回调函数
client.on_connect = on_connect
client.on_message = on_message
# 连接MQTT服务器
client.connect("mqtt.server.com", 1883, 60)
# 发布消息
client.publish("chatgpt/api", "Hello, ChatGPT!")
# 循环监听消息
client.loop_forever()
```
请注意,这只是一个示例代码,您需要根据实际情况进行修改。
使用c 编写一个mqtt 通讯协议的程序
要编写MQTT通讯协议的程序,你需要使用MQTT的C语言库。以下是使用Paho MQTT C库编写MQTT客户端的示例代码。
```c
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "MQTTClient.h"
#define ADDRESS "tcp://localhost:1883"
#define CLIENTID "ExampleClientPub"
#define TOPIC "MQTT Examples"
#define PAYLOAD "Hello World!"
#define QOS 1
#define TIMEOUT 10000L
int main(int argc, char* argv[])
{
MQTTClient client;
MQTTClient_connectOptions conn_opts = MQTTClient_connectOptions_initializer;
MQTTClient_message pubmsg = MQTTClient_message_initializer;
MQTTClient_deliveryToken token;
int rc;
MQTTClient_create(&client, ADDRESS, CLIENTID, MQTTCLIENT_PERSISTENCE_NONE, NULL);
conn_opts.keepAliveInterval = 20;
conn_opts.cleansession = 1;
if ((rc = MQTTClient_connect(client, &conn_opts)) != MQTTCLIENT_SUCCESS)
{
printf("Failed to connect, return code %d\n", rc);
exit(-1);
}
pubmsg.payload = PAYLOAD;
pubmsg.payloadlen = strlen(PAYLOAD);
pubmsg.qos = QOS;
pubmsg.retained = 0;
MQTTClient_publishMessage(client, TOPIC, &pubmsg, &token);
printf("Waiting for up to %d seconds for publication of %s\n"
"on topic %s for client with ClientID: %s\n",
(int)(TIMEOUT/1000), PAYLOAD, TOPIC, CLIENTID);
rc = MQTTClient_waitForCompletion(client, token, TIMEOUT);
printf("Message with delivery token %d delivered\n", token);
MQTTClient_disconnect(client, 10000);
MQTTClient_destroy(&client);
return rc;
}
```
这个示例程序使用TCP连接到本地主机的MQTT代理,发布一个消息到“MQTT Examples”主题,然后关闭连接。你可以修改示例程序以满足你的需求,包括订阅主题、处理接收到的消息等。