"# Node.js\u901a\u8fc7MQTT\u63a5\u5165\u793a\u4f8b\n\n> 2024-04-07 | 2024-04-07\n> https:\/\/www.modbus.cn\/en\/docs\/node-js\n\n---\n\n### \u6982\u8ff0\n\n\u672c\u6587\u4ee5Node.js\u4e3a\u4f8b\uff0c\u4ecb\u7ecd\u901a\u8fc7MQTTS\/MQTT\u534f\u8bae\u63a5\u5165\u5e73\u53f0\uff0c\u57fa\u4e8e\u5e73\u53f0\u63a5\u53e3\u5b9e\u73b0\u201c\u5c5e\u6027\u4e0a\u62a5\u201d\u3001\u201c\u8ba2\u9605\u63a5\u6536\u547d\u4ee4\u201d\u7b49\u529f\u80fd\u3002\n\n**\u8bf4\u660e\uff1a**\n\n\u672c\u6587\u4e2d\u4f7f\u7528\u7684\u4ee3\u7801\u4e3a\u6837\u4f8b\u4ee3\u7801\uff0c\u4ec5\u7528\u4e8e\u4f53\u9a8c\u5e73\u53f0\u901a\u4fe1\u529f\u80fd\uff0c\u5982\u9700\u8fdb\u884c\u5546\u7528\uff0c\u53ef\u4ee5\u53c2\u8003[\u8d44\u6e90\u83b7\u53d6](https:\/\/support.huaweicloud.com\/devg-iothub\/iot_02_1004.html)\u83b7\u53d6\u5bf9\u5e94\u8bed\u8a00\u7684IoT Device SDK\u8fdb\u884c\u96c6\u6210\u3002\n\n### \u524d\u63d0\u6761\u4ef6\n\n- \u5df2\u5b89\u88c5Node.js\uff0c\u82e5\u672a\u5b89\u88c5\u8bf7\u53c2\u8003[\u5b89\u88c5Node.js](https:\/\/support.huaweicloud.com\/devg-iothub\/iot_02_2133.html#ZH-CN_TOPIC_0232966960__section448405171017)\u3002\n\n- \u5df2\u5728\u7ba1\u7406\u63a7\u5236\u53f0\u83b7\u53d6\u8bbe\u5907\u63a5\u5165\u5730\u5740\u3002\u83b7\u53d6\u5730\u5740\u7684\u64cd\u4f5c\u6b65\u9aa4\uff0c\u8bf7\u53c2\u8003\u5e73\u53f0\u5bf9\u63a5\u4fe1\u606f\u3002\n\n- \u5df2\u5728\u7ba1\u7406\u63a7\u5236\u53f0\u521b\u5efa\u4ea7\u54c1\u548c\u8bbe\u5907\u3002\u521b\u5efa\u4ea7\u54c1\u548c\u8bbe\u5907\u7684\u5177\u4f53\u64cd\u4f5c\u7ec6\u8282\uff0c\u8bf7\u53c2\u8003\u521b\u5efa\u4ea7\u54c1\u3001\u6ce8\u518c\u5355\u4e2a\u8bbe\u5907\u6216\u6279\u91cf\u6ce8\u518c\u8bbe\u5907\u3002\n\n### \u51c6\u5907\u5de5\u4f5c\n\n- \u5b89\u88c5Node.js\u8bbf\u95ee[Node.js\u5b98\u7f51](https:\/\/nodejs.org\/en\/download\/)\uff0c\u9009\u62e9\u5408\u9002\u7cfb\u7edf\u7684\u7248\u672c\u4e0b\u8f7d\u3002\uff08\u672c\u6587\u4ee5windows 64-bit\u7cfb\u7edf\uff0cNode.js\u7248\u672cv12.18.0\uff08npm 6.14.4\uff09\u4e3a\u4f8b\uff09\u3002\n\n- \u4e0b\u8f7d\u5b8c\u6210\u540e\uff0c\u8fd0\u884c\u5b89\u88c5\u6587\u4ef6\uff0c\u6839\u636e\u754c\u9762\u63d0\u793a\u5b89\u88c5\u3002\n\n- \u68c0\u67e5Node.js\u662f\u5426\u5b89\u88c5\u6210\u529f\u3002Win\u952e + r -->\u8f93\u5165 cmd-->\u56de\u8f66\uff0c\u8fdb\u5165\u547d\u4ee4\u884c\u7a97\u53e3\u3002\u8f93\u5165node \u2013v\uff0c\u56de\u8f66\u540e\u663e\u793aNode.js\u7248\u672c\uff0c\u8f93\u5165npm -v\u663e\u793a\u7248\u672c\u4fe1\u606f\uff0c\u5373\u8868\u793a\u5b89\u88c5\u6210\u529f\n\n```\nconst mqtt = require('mqtt')\nconst fs = require('fs');\n\n\/\/ MQTT \u670d\u52a1\u5668\u5730\u5740\nconst MQTT_BROKER = "iot.modbus.cn";\n\/\/ MQTT \u7aef\u53e3\u53f7\nconst MQTT_PORT = 1883;\n\/\/ MQTT \u5ba2\u6237\u7aef ID\nconst MQTT_CLIENT_ID = "4QR8TZ9ThuL4G";\n\/\/ MQTT \u7528\u6237\u540d\nconst MQTT_USERNAME = "ceshi";\n\/\/ MQTT \u5bc6\u7801\nconst MQTT_PASSWORD = "123456";\n\/\/ \u8ba2\u9605\u7684\u4e3b\u9898\nconst MQTT_TOPIC_SUBSCRIBE = "\/server\/coo\/4QR8TZ9ThuL4G";\n\/\/ \u53d1\u5e03\u7684\u4e3b\u9898\nconst MQTT_TOPIC_PUBLISH = "\/dev\/coo\/4QR8TZ9ThuL4G";\n\n\/\/ \u521b\u5efa MQTT \u5ba2\u6237\u7aef\nconst client = mqtt.connect({\n    host: MQTT_BROKER,\n    port: MQTT_PORT,\n    clientId: MQTT_CLIENT_ID,\n    username: MQTT_USERNAME,\n    password: MQTT_PASSWORD\n});\n\n\/\/ \u8fde\u63a5\u6210\u529f\u56de\u8c03\u51fd\u6570\nclient.on('connect', function () {\n    console.log("Connected with result code " + MQTT_CLIENT_ID);\n    \/\/ \u8ba2\u9605\u4e3b\u9898\n    client.subscribe(MQTT_TOPIC_SUBSCRIBE);\n});\n\n\/\/ \u63a5\u6536\u6d88\u606f\u56de\u8c03\u51fd\u6570\nclient.on('message', function (topic, message) {\n    console.log(`Received message: ${topic} ${message.toString()}`);\n});\n\n\/\/ \u53d1\u5e03\u6d88\u606f\nfunction publishMessage(client, topic, payload) {\n    client.publish(topic, payload);\n}\n\n\/\/ \u5fc3\u8df3\u51fd\u6570\nfunction sendHeartbeat() {\n    console.log("Sending heartbeat");\n    \/\/ \u53d1\u9001\u5fc3\u8df3\u6d88\u606f\n    publishMessage(client, MQTT_TOPIC_PUBLISH, "heartbeat");\n    \/\/ \u5b9a\u65f6\u8c03\u7528\u81ea\u8eab\n    setTimeout(sendHeartbeat, 60 * 1000);\n}\n\n\/\/ \u5b9a\u65f6\u4e0a\u62a5\u51fd\u6570\nfunction reportData() {\n    console.log("Reporting data");\n    \/\/ \u5f85\u4e0a\u62a5\u7684\u6570\u636e\n    const message = [\n    { "sensor_device_id": 1, "port_id": 1, "sdata": 33 },\n    { "sensor_device_id": 1, "port_id": 2, "sdata": 60 }\n];\nconst payload = JSON.stringify(message);\n\/\/ \u53d1\u5e03\u6570\u636e\npublishMessage(client, MQTT_TOPIC_PUBLISH, payload);\n\/\/ \u5b9a\u65f6\u8c03\u7528\u81ea\u8eab\nsetTimeout(reportData, 10 * 1000);\n}\n\n\/\/ \u542f\u52a8\u5fc3\u8df3\u5b9a\u65f6\u5668\nsendHeartbeat();\n\n\/\/ \u542f\u52a8\u5b9a\u65f6\u4e0a\u62a5\u5b9a\u65f6\u5668\nreportData();\n```\n\n- `require('mqtt')`\uff1a\u5f15\u5165\u4e86 mqtt \u5e93\uff0c\u7528\u4e8e\u63d0\u4f9b MQTT \u5ba2\u6237\u7aef\u7684\u529f\u80fd\u3002\u8fd9\u662f\u4e00\u4e2a MQTT \u5ba2\u6237\u7aef\u6a21\u5757\uff0c\u7528\u4e8e Node.js \u5e94\u7528\u7a0b\u5e8f\u3002\n\n- `require('fs')`\uff1a\u5f15\u5165\u4e86 fs \u5e93\uff0c\u7528\u4e8e\u5904\u7406\u6587\u4ef6\u7cfb\u7edf\u64cd\u4f5c\u3002\u5728\u672c\u793a\u4f8b\u4e2d\uff0c\u5b83\u5e76\u672a\u4f7f\u7528\u3002\n\n- \u58f0\u660e\u548c\u521d\u59cb\u5316\u4e00\u4e9b\u5168\u5c40\u5e38\u91cf\uff0c\u6bd4\u5982 MQTT \u670d\u52a1\u5668\u7684\u5730\u5740\u3001\u7aef\u53e3\u53f7\u3001\u5ba2\u6237\u7aefID\u3001\u7528\u6237\u540d\u3001\u5bc6\u7801\u4ee5\u53ca\u7528\u4e8e\u8ba2\u9605\u548c\u53d1\u5e03\u7684\u4e3b\u9898\u3002\n\n- \u4f7f\u7528 `mqtt.connect()` \u65b9\u6cd5\u8fde\u63a5\u5230 MQTT \u670d\u52a1\u5668\uff0c\u8fd9\u4e2a\u65b9\u6cd5\u9700\u8981\u63d0\u4f9b\u670d\u52a1\u5668\u7684\u5730\u5740\u3001\u7aef\u53e3\u53f7\u3001\u5ba2\u6237\u7aefID\u3001\u7528\u6237\u540d\u548c\u5bc6\u7801\u3002\n\n- \u4f7f\u7528 `client.on('connect', callback)` \u65b9\u6cd5\u8bbe\u7f6e\u5f53\u8fde\u63a5\u6210\u529f\u65f6\u7684\u56de\u8c03\u51fd\u6570\uff0c\u8fd9\u4e2a\u51fd\u6570\u4f1a\u8ba2\u9605 MQTT \u670d\u52a1\u5668\u7684\u4e00\u4e2a\u4e3b\u9898\u3002\n\n- \u4f7f\u7528 `client.on('message', callback)` \u65b9\u6cd5\u8bbe\u7f6e\u5f53\u63a5\u6536\u5230\u6d88\u606f\u65f6\u7684\u56de\u8c03\u51fd\u6570\uff0c\u8fd9\u4e2a\u51fd\u6570\u4f1a\u6253\u5370\u51fa\u63a5\u6536\u5230\u7684\u6d88\u606f\u3002\n\n- `publishMessage()` \u51fd\u6570\u7528\u4e8e\u53d1\u5e03\u6d88\u606f\u5230 MQTT \u670d\u52a1\u5668\u7684\u6307\u5b9a\u4e3b\u9898\u3002\n\n- `sendHeartbeat()` \u51fd\u6570\u7528\u4e8e\u5b9a\u671f\u5411 MQTT \u670d\u52a1\u5668\u53d1\u9001\u5fc3\u8df3\u6d88\u606f\uff0c\u7528\u4e8e\u544a\u77e5\u670d\u52a1\u5668\u5ba2\u6237\u7aef\u8fd8\u5728\u7ebf\u3002\n\n- `reportData()` \u51fd\u6570\u7528\u4e8e\u5b9a\u671f\u5411 MQTT \u670d\u52a1\u5668\u4e0a\u62a5\u6570\u636e\u3002\n\n- `setTimeout(function, delay)` \u7528\u4e8e\u8bbe\u7f6e\u5b9a\u65f6\u5668\uff0c`function` \u662f\u5b9a\u65f6\u5668\u89e6\u53d1\u65f6\u9700\u8981\u6267\u884c\u7684\u51fd\u6570\uff0c`delay` \u662f\u89e6\u53d1\u5b9a\u65f6\u5668\u7684\u5ef6\u8fdf\u65f6\u95f4\uff0c\u5355\u4f4d\u662f\u6beb\u79d2\u3002\n\n\u5728\u8fd0\u884c\u8be5\u793a\u4f8b\u4e4b\u524d\uff0c\u9700\u8981\u786e\u4fdd\u5df2\u7ecf\u5b89\u88c5\u4e86 `mqtt` \u5e93\u3002\u5982\u679c\u8fd8\u672a\u5b89\u88c5\uff0c\u53ef\u4ee5\u4f7f\u7528 npm \u5b89\u88c5\uff0c\u8fd0\u884c\u547d\u4ee4 `npm install mqtt`\u3002\n\n---\n*modbus.cn*\n"