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smart_storage_app/static/lib/mqtt.js

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2026-03-11 08:47:54 +08:00
/**
* MQTT 客户端插件 for uni-app
* 基于 WebSocket 实现 MQTT 协议
*/
class MQTTClient {
/**
* 构造函数
* @param {Object} options 配置选项
*/
constructor(options = {}) {
this.reSetconstructor(options);
// 事件监听器
this.eventListeners = {
connect: [],
disconnect: [],
error: [],
message: [],
statusChange: []
};
// 绑定方法
this.on = this.on.bind(this);
this.off = this.off.bind(this);
this.connect = this.connect.bind(this);
this.disconnect = this.disconnect.bind(this);
this.publish = this.publish.bind(this);
this.subscribe = this.subscribe.bind(this);
this.unsubscribe = this.unsubscribe.bind(this);
}
reSetconstructor(options = {}) {
// 默认配置
this.config = {
path: '/ws',
protocolVersion: 4, // 4 for MQTT 3.1.1
clean: false,
cleanStart: false, // for MQTT 5.0
keepAlive: 60,
sessionExpiryInterval: 4294967295,
connectTimeout: 10000,
reconnectPeriod: 10000
};
// 合并用户配置
Object.assign(this.config, options);
// 状态
this.socket = null;
this.connectionStatus = 'disconnected'; // 'disconnected', 'connecting', 'connected', 'error'
this.subscribedTopics = {};
this.messageId = 1;
this.connectTimeoutTimer = null;
this.reconnectTimer = null;
this.pingIntervalTimer = null;
this.pingTimeoutTimer = null;
}
/**
* 添加事件监听器
* @param {string} event 事件名称: 'connect', 'disconnect', 'error', 'message', 'statusChange'
* @param {Function} callback 回调函数
*/
on(event, callback) {
if (this.eventListeners[event]) {
this.eventListeners[event].push(callback);
}
}
/**
* 移除事件监听器
* @param {string} event 事件名称
* @param {Function} callback 回调函数
*/
off(event, callback) {
if (this.eventListeners[event]) {
const index = this.eventListeners[event].indexOf(callback);
if (index > -1) {
this.eventListeners[event].splice(index, 1);
}
}
}
/**
* 触发事件
* @param {string} event 事件名称
* @param {...any} args 参数
*/
emit(event, ...args) {
if (this.eventListeners[event]) {
this.eventListeners[event].forEach(callback => {
try {
callback(...args);
} catch (err) {
console.error(`Error in ${event} event listener:`, err);
}
});
}
}
/**
* 更新连接状态
* @param {string} status 新状态
*/
setConnectionStatus(status) {
if (this.connectionStatus !== status) {
this.connectionStatus = status;
this.emit('statusChange', status);
}
}
/**
* 连接 MQTT 服务器
*/
connect() {
const {
host,
port,
path,
clientId,
username,
password,
protocolVersion,
clean,
cleanStart,
keepAlive,
sessionExpiryInterval,
connectTimeout
} = this.config;
console.log("连接参数:", this.config)
if (!host) {
this.emit('error', new Error('请输入主机地址'));
return;
}
this.setConnectionStatus('connecting');
this.emit('statusChange', 'connecting');
// 构建 WebSocket URL
let urlPath = path;
if (!urlPath.startsWith('/')) {
urlPath = '/' + urlPath;
}
let url = `ws://${host}:${port}${urlPath}`;
// 关闭现有连接
if (this.socket) {
this.socket.close();
this.socket = null;
}
const ver = protocolVersion === 5 ? '5.0' : protocolVersion === 4 ? '3.1.1' : '3.1';
// 建立 WebSocket 连接
this.socket = uni.connectSocket({
url,
protocols: ['mqtt', 'mqttv3.1.1'],
header: {
'content-type': 'application/octet-stream'
},
success: () => {
// 连接请求已发送
},
fail: (err) => {
this.setConnectionStatus('error');
this.emit('error', new Error(`WebSocket 连接失败: ${JSON.stringify(err)}`));
}
});
// 设置连接超时
if (connectTimeout > 0) {
this.connectTimeoutTimer = setTimeout(() => {
if (this.connectionStatus === 'connecting') {
this.setConnectionStatus('error');
this.emit('error', new Error(`连接超时 (${connectTimeout}ms)`));
if (this.socket) {
this.socket.close();
this.socket = null;
}
}
}, connectTimeout);
}
// WebSocket 事件监听
this.socket.onOpen(() => {
console.log('[MQTT调试] WebSocket 连接已打开');
if (this.connectTimeoutTimer) {
clearTimeout(this.connectTimeoutTimer);
this.connectTimeoutTimer = null;
}
this.sendConnectPacket(clientId, username, password, protocolVersion, clean, cleanStart,
keepAlive, sessionExpiryInterval);
});
this.socket.onMessage((res) => {
this.handleMQTTMessage(res.data);
});
this.socket.onError((err) => {
if (this.connectTimeoutTimer) {
clearTimeout(this.connectTimeoutTimer);
this.connectTimeoutTimer = null;
}
this.stopPingInterval();
this.setConnectionStatus('error');
this.emit('error', new Error(`WebSocket 错误: ${JSON.stringify(err)}`));
});
this.socket.onClose((res) => {
console.log('[MQTT调试] WebSocket 关闭,原因:', res);
if (this.connectTimeoutTimer) {
clearTimeout(this.connectTimeoutTimer);
this.connectTimeoutTimer = null;
}
this.stopPingInterval();
if (this.connectionStatus === 'connected' && this.config.reconnectPeriod > 0) {
this.reconnectTimer = setTimeout(() => {
this.connect();
}, this.config.reconnectPeriod);
}
this.setConnectionStatus('disconnected');
this.emit('disconnect', res);
});
}
/**
* 断开连接
*/
disconnect() {
if (this.connectTimeoutTimer) {
clearTimeout(this.connectTimeoutTimer);
this.connectTimeoutTimer = null;
}
if (this.reconnectTimer) {
clearTimeout(this.reconnectTimer);
this.reconnectTimer = null;
}
// 清除心跳超时定时器
if (this.pingTimeoutTimer) {
clearTimeout(this.pingTimeoutTimer);
this.pingTimeoutTimer = null;
}
this.stopPingInterval();
if (this.socket) {
this.sendDisconnectPacket();
setTimeout(() => {
this.socket.close();
this.socket = null;
this.setConnectionStatus('disconnected');
this.subscribedTopics = {};
}, 100);
}
}
/**
* 发布消息
* @param {string} topic 主题
* @param {string} message 消息内容
* @param {number} qos QoS 等级 (0, 1, 2)
*/
publish(topic, message, qos = 0) {
if (this.connectionStatus !== 'connected') {
this.emit('error', new Error('请先连接'));
return;
}
if (!topic) {
this.emit('error', new Error('请输入主题'));
return;
}
try {
this.sendPublishPacket(topic, message, qos);
this.emit('message', {
type: 'send',
topic,
message
});
} catch (error) {
this.emit('error', new Error(`发布失败: ${error.message}`));
}
}
/**
* 订阅主题
* @param {string} topic 主题
* @param {number} qos QoS 等级 (0, 1, 2)
*/
subscribe(topic, qos = 0) {
if (this.connectionStatus !== 'connected') {
this.emit('error', new Error('请先连接'));
return;
}
if (!topic) {
this.emit('error', new Error('请输入订阅主题'));
return;
}
try {
this.sendSubscribePacket(topic, qos);
this.subscribedTopics[topic] = qos;
} catch (error) {
this.emit('error', new Error(`订阅失败: ${error.message}`));
}
}
/**
* 取消订阅
* @param {string} topic 主题
*/
unsubscribe(topic) {
if (this.connectionStatus !== 'connected') {
this.emit('error', new Error('请先连接'));
return;
}
if (!topic) {
this.emit('error', new Error('请输入取消订阅的主题'));
return;
}
try {
this.sendUnsubscribePacket(topic);
delete this.subscribedTopics[topic];
} catch (error) {
this.emit('error', new Error(`取消订阅失败: ${error.message}`));
}
}
/**
* 获取当前连接状态
* @returns {string} 连接状态
*/
getStatus() {
return this.connectionStatus;
}
/**
* 获取已订阅的主题列表
* @returns {Array} 主题列表
*/
getSubscribedTopics() {
return Object.keys(this.subscribedTopics);
}
// ========== 内部方法 ==========
/**
* 发送数据包
* @param {string|ArrayBuffer|Array} packet 数据包
*/
sendPacket(packet) {
if (!this.socket) {
return;
}
console.log("sendPacket", packet)
let arrayBuffer;
if (typeof packet === 'string') {
const bytes = this.ab2buffer(packet);
arrayBuffer = new Uint8Array(bytes).buffer;
// 调试日志:记录发送的数据包
console.log('MQTT 发送数据包(字符串):', packet.length, '字符,字节:', bytes.length);
console.log('数据包字节前64字节:', bytes.slice(0, 64).map(b => b.toString(16).padStart(2, '0')).join(' '));
} else if (packet instanceof ArrayBuffer) {
arrayBuffer = packet;
console.log('MQTT 发送数据包ArrayBuffer:', arrayBuffer.byteLength, '字节');
} else if (Array.isArray(packet)) {
arrayBuffer = new Uint8Array(packet).buffer;
console.log('MQTT 发送数据包(数组):', packet.length, '字节');
} else {
this.emit('error', new Error('未知的数据包格式'));
return;
}
uni.sendSocketMessage({
data: arrayBuffer,
success: () => {
// 发送成功
console.log('MQTT 数据包发送成功');
},
fail: (err) => {
console.error('MQTT 数据包发送失败:', err);
this.emit('error', new Error(`数据发送失败: ${JSON.stringify(err)}`));
}
});
}
/**
* 处理 MQTT 消息
* @param {*} data 原始数据
*/
handleMQTTMessage(data) {
try {
console.log('[MQTT调试] 收到原始消息:', typeof data, data instanceof ArrayBuffer, data.byteLength || data
.length);
const buffer = this.ab2buffer(data);
console.log('[MQTT调试] 转换后的 buffer 长度:', buffer.length);
if (buffer.length > 0) {
const hexStr = buffer.slice(0, Math.min(32, buffer.length)).map(b => b.toString(16).padStart(2,
'0')).join(' ');
console.log('[MQTT调试] buffer 前32字节hex:', hexStr);
}
if (buffer.length === 0) {
return;
}
const packetType = buffer[0] & 0xF0;
const flags = buffer[0] & 0x0F;
console.log('[MQTT调试] 数据包类型:', '0x' + packetType.toString(16).padStart(2, '0'), '标志位:', flags);
let pos = 1;
let remainingLength = 0;
let multiplier = 1;
let encodedByte;
do {
if (pos >= buffer.length) {
console.log('[MQTT调试] 剩余长度编码不完整');
return;
}
encodedByte = buffer[pos];
remainingLength += (encodedByte & 0x7F) * multiplier;
multiplier *= 128;
pos++;
} while ((encodedByte & 0x80) !== 0 && pos < buffer.length);
console.log('[MQTT调试] 剩余长度:', remainingLength, '当前位置:', pos);
if (packetType === 0x20) {
console.log('[MQTT调试] 处理 CONNACK 包');
this.handleConnackPacket(buffer, pos);
} else if (packetType === 0x30 || packetType === 0x32) {
console.log('[MQTT调试] 处理 PUBLISH 包');
this.handlePublishPacket(buffer, pos, flags);
} else if (packetType === 0x40) {
console.log('[MQTT调试] 处理 PUBACK 包');
this.handlePubackPacket(buffer, pos);
} else if (packetType === 0x90) {
console.log('[MQTT调试] 处理 SUBACK 包');
this.handleSubackPacket(buffer, pos);
} else if (packetType === 0xB0) {
console.log('[MQTT调试] 处理 UNSUBACK 包');
this.handleUnsubackPacket(buffer, pos);
} else if (packetType === 0xD0) {
console.log('[MQTT调试] 处理 PINGRESP 包');
// 清除心跳响应超时定时器
if (this.pingTimeoutTimer) {
clearTimeout(this.pingTimeoutTimer);
this.pingTimeoutTimer = null;
console.log('[MQTT调试] 心跳响应超时定时器已清除');
}
} else if (packetType === 0xE0) {
console.log('[MQTT调试] 处理 DISCONNECT 包');
this.handleDisconnectPacket(buffer, pos);
} else {
console.log('[MQTT调试] 未知数据包类型:', packetType.toString(16));
}
} catch (error) {
console.error('[MQTT调试] 处理 MQTT 消息时出错:', error);
this.emit('error', new Error(`处理 MQTT 消息时出错: ${error.message}`));
}
}
/**
* 处理 CONNACK
*/
handleConnackPacket(buffer, pos) {
if (buffer.length < pos + 2) {
this.emit('error', new Error('CONNACK 包长度不足'));
return;
}
const flags = buffer[pos++];
const reasonCode = buffer[pos++];
const reasonCodes = {
0: '成功',
128: '协议版本错误',
129: '客户端ID被拒绝',
130: '服务器不可用',
131: '用户名密码错误',
132: '未授权',
133: '服务器未找到',
134: '服务器不可用',
135: '用户名密码无效'
};
const reasonText = reasonCodes[reasonCode] || `未知错误 (${reasonCode})`;
if (reasonCode === 0) {
console.log('[MQTT调试] CONNACK 成功,设置连接状态为 connected');
this.setConnectionStatus('connected');
this.emit('connect');
this.startPingInterval();
// 重新订阅之前订阅的主题
if (Object.keys(this.subscribedTopics).length > 0) {
console.log('[MQTT调试] 重新订阅之前订阅的主题');
for (const topic in this.subscribedTopics) {
const qos = this.subscribedTopics[topic];
try {
this.sendSubscribePacket(topic, qos);
console.log(`[MQTT调试] 重新订阅主题: ${topic}, QoS: ${qos}`);
} catch (err) {
console.error(`[MQTT调试] 重新订阅主题失败: ${topic}`, err);
}
}
}
} else {
this.setConnectionStatus('error');
this.emit('error', new Error(`MQTT 连接失败: ${reasonText}`));
}
}
/**
* 处理 PUBLISH
*/
handlePublishPacket(buffer, pos, flags) {
try {
console.log('[MQTT调试] 开始处理 PUBLISH 包buffer 长度:', buffer.length, '起始位置:', pos, '标志位:', flags);
const qos = (flags >> 1) & 0x03;
console.log('[MQTT调试] 解析出的 QoS:', qos);
if (buffer.length < pos + 2) {
console.error('[MQTT调试] PUBLISH 包主题长度字段不完整');
this.emit('error', new Error('PUBLISH 包主题长度字段不完整'));
return;
}
const topicLen = buffer[pos++] * 256 + buffer[pos++];
console.log('[MQTT调试] 主题长度:', topicLen);
if (buffer.length < pos + topicLen) {
console.error('[MQTT调试] PUBLISH 包主题数据不完整');
this.emit('error', new Error('PUBLISH 包主题数据不完整'));
return;
}
const topicBytes = buffer.slice(pos, pos + topicLen);
const topicHex = topicBytes.slice(0, Math.min(32, topicBytes.length)).map(b => b.toString(16).padStart(
2, '0')).join(' ');
console.log('[MQTT调试] 主题原始字节hex:', topicHex);
const topic = this.bytesToString(topicBytes);
console.log('[MQTT调试] 解析出的主题:', topic);
pos += topicLen;
let packetId = 0;
if (qos > 0) {
if (buffer.length < pos + 2) {
console.error('[MQTT调试] PUBLISH 包包ID字段不完整');
this.emit('error', new Error('PUBLISH 包包ID字段不完整'));
return;
}
packetId = buffer[pos++] * 256 + buffer[pos++];
console.log('[MQTT调试] 报文标识符:', packetId);
}
const payloadBytes = buffer.slice(pos);
console.log('[MQTT调试] 载荷字节长度:', payloadBytes.length);
if (payloadBytes.length > 0) {
const payloadHex = payloadBytes.slice(0, Math.min(64, payloadBytes.length)).map(b => b.toString(16)
.padStart(2, '0')).join(' ');
console.log('[MQTT调试] 载荷前64字节hex:', payloadHex);
}
const payload = this.bytesToString(payloadBytes);
console.log('[MQTT调试] 解析出的载荷:', payload);
this.emit('message', {
type: 'receive',
topic,
payload
});
if (qos === 1) {
this.sendPubackPacket(packetId);
}
} catch (error) {
console.error('[MQTT调试] 处理 PUBLISH 包时出错:', error);
this.emit('error', new Error(`处理 PUBLISH 包时出错: ${error.message}`));
}
}
/**
* 处理 PUBACK
*/
handlePubackPacket(buffer, pos) {
if (buffer.length >= pos + 2) {
const packetId = buffer[pos++] * 256 + buffer[pos++];
// 可以触发事件
}
}
/**
* 处理 SUBACK
*/
handleSubackPacket(buffer, pos) {
if (buffer.length >= pos + 2) {
const packetId = buffer[pos++] * 256 + buffer[pos++];
this.emit('subscribed', packetId);
}
}
/**
* 处理 UNSUBACK
*/
handleUnsubackPacket(buffer, pos) {
if (buffer.length >= pos + 2) {
const packetId = buffer[pos++] * 256 + buffer[pos++];
this.emit('unsubscribed', packetId);
}
}
/**
* 处理 DISCONNECT
*/
handleDisconnectPacket(buffer, pos) {
this.setConnectionStatus('disconnected');
this.emit('disconnect', {
type: 'server'
});
}
/**
* 发送 CONNECT
*/
sendConnectPacket(clientId, username, password, protocolVersion, clean, cleanStart, keepAlive,
sessionExpiryInterval) {
try {
console.log('[MQTT调试] 发送 CONNECT 包clean:', clean, 'cleanStart:', cleanStart, 'protocolVersion:',
protocolVersion);
let packet = '';
packet += String.fromCharCode(0x10);
let variableHeader = '';
variableHeader += String.fromCharCode(0x00, 0x04);
variableHeader += 'MQTT';
variableHeader += String.fromCharCode(protocolVersion);
let flags = 0x00;
if (protocolVersion === 5) {
if (cleanStart) flags |= 0x02;
} else {
if (clean) flags |= 0x02;
}
if (username) flags |= 0x80;
if (password) flags |= 0x40;
variableHeader += String.fromCharCode(flags);
variableHeader += String.fromCharCode((keepAlive >> 8) & 0xFF, keepAlive & 0xFF);
// MQTT 5.0 属性处理
if (protocolVersion === 5) {
let properties = '';
let propertyLength = 0;
// 添加会话过期间隔属性 (0x11)
if (!cleanStart && sessionExpiryInterval !== undefined) {
properties += String.fromCharCode(0x11); // 属性标识符
properties += String.fromCharCode((sessionExpiryInterval >> 24) & 0xFF);
properties += String.fromCharCode((sessionExpiryInterval >> 16) & 0xFF);
properties += String.fromCharCode((sessionExpiryInterval >> 8) & 0xFF);
properties += String.fromCharCode(sessionExpiryInterval & 0xFF);
propertyLength += 1 + 4; // 标识符 + 4字节值
}
// 编码属性长度为可变字节整数
let encodedPropertyLength = '';
let propLen = propertyLength;
do {
let byte = propLen % 128;
propLen = Math.floor(propLen / 128);
if (propLen > 0) {
byte |= 0x80;
}
encodedPropertyLength += String.fromCharCode(byte);
} while (propLen > 0);
variableHeader += encodedPropertyLength;
variableHeader += properties;
}
let payload = this.encodeString(clientId);
if (username) payload += this.encodeString(username);
if (password) payload += this.encodeString(password);
const remainingLength = variableHeader.length + payload.length;
packet += this.encodeRemainingLength(remainingLength);
packet += variableHeader;
packet += payload;
this.sendPacket(packet);
} catch (error) {
this.emit('error', new Error(`发送 CONNECT 包失败: ${error.message}`));
}
}
/**
* 发送 DISCONNECT
*/
sendDisconnectPacket() {
let packet = String.fromCharCode(0xE0);
packet += String.fromCharCode(0x00);
this.sendPacket(packet);
}
/**
* 发送 PUBLISH
*/
sendPublishPacket(topic, message, qos) {
let packet = '';
const flags = 0x30 | (qos << 1);
packet += String.fromCharCode(flags);
const topicBytes = this.encodeString(topic);
const msgBytes = this.stringToBytes(message);
let remainingLength = topicBytes.length + msgBytes.length;
if (qos > 0) {
remainingLength += 2;
packet += this.encodeRemainingLength(remainingLength);
packet += topicBytes;
packet += String.fromCharCode((this.messageId >> 8) & 0xFF, this.messageId & 0xFF);
this.messageId++;
} else {
packet += this.encodeRemainingLength(remainingLength);
packet += topicBytes;
}
packet += msgBytes;
this.sendPacket(packet);
}
/**
* 发送 SUBSCRIBE
*/
sendSubscribePacket(topic, qos) {
let packet = String.fromCharCode(0x82);
const topicBytes = this.encodeString(topic);
let remainingLength = 2 + topicBytes.length + 1; // packetId + topicBytes + qos
if (this.config.protocolVersion === 5) {
remainingLength += 1; // property length byte (0x00)
}
packet += this.encodeRemainingLength(remainingLength);
packet += String.fromCharCode((this.messageId >> 8) & 0xFF, this.messageId & 0xFF);
if (this.config.protocolVersion === 5) {
packet += String.fromCharCode(0x00); // property length = 0
}
packet += topicBytes;
packet += String.fromCharCode(qos);
this.messageId++;
this.sendPacket(packet);
}
/**
* 发送 UNSUBSCRIBE
*/
sendUnsubscribePacket(topic) {
let packet = String.fromCharCode(0xA2);
const topicBytes = this.encodeString(topic);
let remainingLength = 2 + topicBytes.length; // packetId + topicBytes
if (this.config.protocolVersion === 5) {
remainingLength += 1; // property length byte (0x00)
}
packet += this.encodeRemainingLength(remainingLength);
packet += String.fromCharCode((this.messageId >> 8) & 0xFF, this.messageId & 0xFF);
if (this.config.protocolVersion === 5) {
packet += String.fromCharCode(0x00); // property length = 0
}
packet += topicBytes;
this.messageId++;
this.sendPacket(packet);
}
/**
* 发送 PUBACK
*/
sendPubackPacket(packetId) {
try {
let packet = String.fromCharCode(0x40);
packet += String.fromCharCode(0x02);
packet += String.fromCharCode((packetId >> 8) & 0xFF, packetId & 0xFF);
this.sendPacket(packet);
} catch (error) {
this.emit('error', new Error(`发送 PUBACK 失败: ${error.message}`));
}
}
/**
* 发送 PINGREQ
*/
sendPingPacket() {
try {
// 清除之前的超时定时器
if (this.pingTimeoutTimer) {
clearTimeout(this.pingTimeoutTimer);
this.pingTimeoutTimer = null;
}
console.log('[MQTT调试] 发送 PINGREQ 包');
let packet = String.fromCharCode(0xC0);
packet += String.fromCharCode(0x00);
this.sendPacket(packet);
// 设置心跳响应超时定时器
const {
keepAlive
} = this.config;
if (keepAlive > 0) {
const timeout = keepAlive * 1000 * 1.5; // 1.5倍keepAlive时间
console.log('[MQTT调试] 设置心跳响应超时:', timeout, 'ms');
this.pingTimeoutTimer = setTimeout(() => {
console.log('[MQTT调试] 心跳响应超时,服务器未回复 PINGRESP');
this.emit('error', new Error('心跳响应超时,服务器未回复 PINGRESP'));
// 主动断开连接
this.disconnect();
}, timeout);
}
} catch (error) {
this.emit('error', new Error(`发送 PINGREQ 失败: ${error.message}`));
}
}
/**
* 启动心跳定时器
*/
startPingInterval() {
this.stopPingInterval();
const {
keepAlive
} = this.config;
console.log('[MQTT调试] 启动心跳定时器keepAlive:', keepAlive);
if (keepAlive > 0) {
const interval = (keepAlive * 1000) * 0.8;
console.log('[MQTT调试] 心跳间隔:', interval, 'ms');
this.pingIntervalTimer = setInterval(() => {
if (this.connectionStatus === 'connected') {
console.log('[MQTT调试] 发送心跳 PINGREQ');
this.sendPingPacket();
}
}, interval);
}
}
/**
* 停止心跳定时器
*/
stopPingInterval() {
if (this.pingIntervalTimer) {
console.log('[MQTT调试] 停止心跳定时器');
clearInterval(this.pingIntervalTimer);
this.pingIntervalTimer = null;
}
// 清除心跳响应超时定时器
if (this.pingTimeoutTimer) {
clearTimeout(this.pingTimeoutTimer);
this.pingTimeoutTimer = null;
console.log('[MQTT调试] 心跳响应超时定时器已清除');
}
}
// ========== 工具方法 ==========
/**
* 将各种数据格式转换为字节数组
*/
ab2buffer(data) {
try {
if (typeof data === 'string') {
const bytes = [];
for (let i = 0; i < data.length; i++) {
bytes.push(data.charCodeAt(i) & 0xFF);
}
return bytes;
} else if (data instanceof ArrayBuffer) {
return Array.from(new Uint8Array(data));
} else if (Array.isArray(data)) {
return data;
} else {
return Array.from(data);
}
} catch (error) {
this.emit('error', new Error(`数据转换失败: ${error.message}`));
return [];
}
}
/**
* 字节数组转字符串UTF-8 解码
*/
bytesToString(bytes) {
try {
if (!bytes || bytes.length === 0) return '';
// 优先使用 TextDecoder 进行 UTF-8 解码
if (typeof TextDecoder !== 'undefined') {
try {
const decoder = new TextDecoder('utf-8');
const array = new Uint8Array(bytes);
return decoder.decode(array);
} catch (decodeError) {
console.warn('TextDecoder 解码失败,回退到手动解码:', decodeError);
}
}
// 手动 UTF-8 解码
let result = '';
let i = 0;
while (i < bytes.length) {
const byte = bytes[i];
// ASCII 字符 (0-127)
if (byte < 128) {
result += String.fromCharCode(byte);
i++;
}
// 2字节 UTF-8 字符
else if ((byte & 0xE0) === 0xC0 && i + 1 < bytes.length) {
const byte2 = bytes[i + 1];
if ((byte2 & 0xC0) === 0x80) {
const codePoint = ((byte & 0x1F) << 6) | (byte2 & 0x3F);
result += String.fromCharCode(codePoint);
i += 2;
} else {
// 无效的 UTF-8 序列,跳过
i++;
}
}
// 3字节 UTF-8 字符
else if ((byte & 0xF0) === 0xE0 && i + 2 < bytes.length) {
const byte2 = bytes[i + 1];
const byte3 = bytes[i + 2];
if ((byte2 & 0xC0) === 0x80 && (byte3 & 0xC0) === 0x80) {
const codePoint = ((byte & 0x0F) << 12) | ((byte2 & 0x3F) << 6) | (byte3 & 0x3F);
result += String.fromCharCode(codePoint);
i += 3;
} else {
// 无效的 UTF-8 序列,跳过
i++;
}
}
// 4字节 UTF-8 字符(代理对)
else if ((byte & 0xF8) === 0xF0 && i + 3 < bytes.length) {
const byte2 = bytes[i + 1];
const byte3 = bytes[i + 2];
const byte4 = bytes[i + 3];
if ((byte2 & 0xC0) === 0x80 && (byte3 & 0xC0) === 0x80 && (byte4 & 0xC0) === 0x80) {
const codePoint = ((byte & 0x07) << 18) | ((byte2 & 0x3F) << 12) | ((byte3 & 0x3F) << 6) | (
byte4 & 0x3F);
// 代理对处理
if (codePoint <= 0xFFFF) {
result += String.fromCharCode(codePoint);
} else {
// 转换为代理对
const highSurrogate = 0xD800 + (((codePoint - 0x10000) >> 10) & 0x3FF);
const lowSurrogate = 0xDC00 + ((codePoint - 0x10000) & 0x3FF);
result += String.fromCharCode(highSurrogate, lowSurrogate);
}
i += 4;
} else {
// 无效的 UTF-8 序列,跳过
i++;
}
} else {
// 无效的 UTF-8 序列,跳过
i++;
}
}
return result;
} catch (error) {
console.error('字节转字符串失败:', error);
this.emit('error', new Error(`字节转字符串失败: ${error.message}`));
return '';
}
}
/**
* 编码字符串添加长度前缀
*/
encodeString(str) {
let result = '';
const bytes = this.stringToBytes(str);
result += String.fromCharCode((bytes.length >> 8) & 0xFF);
result += String.fromCharCode(bytes.length & 0xFF);
for (let i = 0; i < bytes.length; i++) {
result += String.fromCharCode(bytes[i]);
}
return result;
}
/**
* 字符串转字节数组UTF-8 编码
*/
stringToBytes(str) {
const bytes = [];
for (let i = 0; i < str.length; i++) {
let code = str.charCodeAt(i);
if (code <= 0x7F) {
// 1字节 UTF-8
bytes.push(code);
} else if (code <= 0x7FF) {
// 2字节 UTF-8
bytes.push(0xC0 | (code >> 6));
bytes.push(0x80 | (code & 0x3F));
} else if (code >= 0xD800 && code <= 0xDFFF) {
// 代理对 - 4字节 UTF-8
i++;
if (i < str.length) {
const high = code;
const low = str.charCodeAt(i);
const fullCode = ((high & 0x3FF) << 10) + (low & 0x3FF) + 0x10000;
bytes.push(0xF0 | (fullCode >> 18));
bytes.push(0x80 | ((fullCode >> 12) & 0x3F));
bytes.push(0x80 | ((fullCode >> 6) & 0x3F));
bytes.push(0x80 | (fullCode & 0x3F));
}
} else {
// 3字节 UTF-8
bytes.push(0xE0 | (code >> 12));
bytes.push(0x80 | ((code >> 6) & 0x3F));
bytes.push(0x80 | (code & 0x3F));
}
}
return bytes;
}
/**
* 编码剩余长度
*/
encodeRemainingLength(length) {
let result = '';
do {
let byte = length % 128;
length = Math.floor(length / 128);
if (length > 0) {
byte |= 0x80;
}
result += String.fromCharCode(byte);
} while (length > 0);
return result;
}
}
// 导出类
export default MQTTClient;