tencent cloud

TDMQ for MQTT

Release Notes and Announcements
Release Notes
Product Introduction
TDMQ Product Series Introduction and Selection
What Is TDMQ for MQTT
Scenarios
Technical Architecture
Product series
MQTT Protocol Compatibility Notes
Comparison with Apache
High Availability
Product Constraints and Usage Quota
Basic Concepts
Supported Regions
Billing
Billing Overview
Renewal Instructions
Viewing Consumption Details
Overdue Payment Instructions
Refund
Getting Started
Guide for Getting Started
Preparations
Public Network Access
VPC Network Access
User Guide
Usage Process Guide
Configuring Account Permission
Creating a Cluster
Managing Topic
Connecting to the Cluster
Querying Messages
Managing Client
Managing a Cluster
Viewing Monitoring Metrics and Configuring Alarm Policies
Data Integration
Integrating Data Into SCF
Integrating Data Into CKafka
Integrating Data into RocketMQ
Development Guide
MQTT 5 Advanced Features
Data Plane HTTP API Description
Quota and Flow Control Mechanism Description
Configuring a Custom Domain Name
Configuring SQL Filtering
Configuring Point-to-Point Subscription
MQTT over QUIC
Managing Client Subscription
Message Enhancement Rule
Use Cases
Must-Knows for MQTT Client Development
Observability
Topic and Wildcard Subscriptions
​​API Reference
History
Introduction
API Category
Making API Requests
Cluster APIs
Topic APIs
Authorization Policy APIs
User APIs
Client APIs
Message Enhancement Rule APIs
Message APIs
Data Types
Error Codes
SDK Reference
Access Point Format
Java SDK
C SDK
Javascript/Node.JS/Mini Program
Go SDK
iOS SDK
JavaScript SDK
Dart SDK
Python SDK
.NET
Security and Compliance
Permission Management
FAQs
Related Agreement
Privacy Policy
Data Privacy And Security Agreement
TDMQ for MQTT Service Level Agreement
Contact Us
DocumentationTDMQ for MQTTSDK ReferenceJavascript/Node.JS/Mini Program

Javascript/Node.JS/Mini Program

Focus Mode
Font Size
Last updated: 2026-04-01 16:37:51

Feature Overview

MQTT.js is a JavaScript module that implements MQTT protocol client functionality and can be used in browser and Node.js environments.
Since JavaScript is single-threaded, MQTT.js is a fully asynchronous MQTT client. It supports MQTT and MQTT over WebSocket, with different levels of support in execution environments as follows:
Browser environment: MQTT over WebSocket (including WeChat mini program, Alipay mini program, and other custom browser environments).
Node.js environment: MQTT and MQTT over WebSocket.
In different environments, except for a few connection parameters, all other APIs are the same.

Environment Preparation

Install using npm:
npm i mqtt
Install using CDN (browser):
<script src="https://unpkg.com/mqtt/dist/mqtt.min.js"></script>
<script>
    // Initialize a global mqtt variable.
    console.log(mqtt)
</script>
In a Node.js environment, you can use the command `npm i mqtt -g` to globally install MQTT.js for command line usage.
npm i mqtt -g

mqtt help

MQTT.js command line interface, available commands are:

  * publish     publish a message to the broker
  * subscribe   subscribe for updates from the broker
  * version     the current MQTT.js version
  * help        help about commands

Launch 'mqtt help [command]' to know more about the commands.

Sample Code

MQTT5
MQTT5 TLS
MQTT3.1.1
MQTT3.1.1 TLS

const mqtt = require('mqtt');

/**
 * MQTT 5.0 TCP Connection Example
 */

// ============ Connection Configuration ============
const serverUri = 'mqtt://mqtt-xxx.mqtt.tencenttdmq.com:1883';
const clientId = 'QuickStart';
const username = 'YOUR_USERNAME';
const password = 'YOUR_PASSWORD';
const pubTopic = 'home/test';
const topicFilters = ['home/test', 'home/#', 'home/+'];
const qos = [1, 1, 1];

// Configure connection options.
const options = {
    clientId: clientId,
    username: username,
    password: password,
    protocolVersion: 5,  // MQTT 5.0
    clean: true,
    reconnectPeriod: 0,  // Disable automatic reconnection.
};

// Create a client and connect.
const client = mqtt.connect(serverUri, options);

// Connection successful
client.on('connect', async () => {
    console.log('Connected');

    try {
        // 2. Subscribe
        for (let i = 0; i < topicFilters.length; i++) {
            await new Promise((resolve, reject) => {
                client.subscribe(topicFilters[i], { qos: qos[i] }, (err) => {
                    if (err) reject(err);
                    else resolve();
                });
            });
        }
        console.log('Subscribed');

        // 3. Publish
        for (let i = 1; i <= 16; i++) {
            await new Promise((resolve, reject) => {
                client.publish(pubTopic, `Message #${i}`, { qos: 1 }, (err) => {
                    if (err) reject(err);
                    else resolve();
                });
            });
            await new Promise(resolve => setTimeout(resolve, 500));
        }
        console.log('Published');

        // 4. Wait to receive
        await new Promise(resolve => setTimeout(resolve, 2000));

        // 5. Disconnect
        client.end();
        console.log('Disconnected');
    } catch (error) {
        console.error('Error:', error.message);
        client.end();
    }
});

// Message receiving and processing
client.on('message', (topic, message) => {
    console.log(`Received message: ${topic} -> ${message.toString()}`);
});

// Error handling
client.on('error', (error) => {
    console.error('Error:', error.message);
});


const mqtt = require('mqtt');
const fs = require('fs');
const tls = require('tls');

/**
 * MQTT 5.0 TLS Encrypted Connection Example
 */

// ============ Connection Configuration ============
const serverUri = 'mqtts://mqtt-xxx.mqtt.tencenttdmq.com:8883';
const clientId = 'QuickStart';
const username = 'YOUR_USERNAME';
const password = 'YOUR_PASSWORD';
const pubTopic = 'home/test';
const topicFilters = ['home/test', 'home/#', 'home/+'];
const qos = [1, 1, 1];

// CA certificate path (optional, used to verify the server certificate)
const caCertPath = null; // e.g., '/path/to/ca.crt'

// Configure connection options (including TLS).
const options = {
    clientId: clientId,
    username: username,
    password: password,
    protocolVersion: 5,  // MQTT 5.0
    clean: true,
    reconnectPeriod: 0,  // Disable automatic reconnection.
    
    // TLS configuration
    rejectUnauthorized: true,  // Production environment: Verify the server certificate
    
    // If a CA certificate is provided, load it.
    ca: caCertPath ? [fs.readFileSync(caCertPath)] : undefined,
    
    // Custom certificate verification
    checkServerIdentity: (host, cert) => {
        return validateServerCertificate(host, cert);
    }
};

/**
 * Verify the server certificate.
 */
function validateServerCertificate(host, cert) {
    // 1. Check the certificate validity period.
    const now = new Date();
    const validFrom = new Date(cert.valid_from);
    const validTo = new Date(cert.valid_to);
    
    if (now < validFrom || now > validTo) {
        const error = new Error(`Certificate verification failed: The certificate has expired or is not yet valid (validity period: ${validFrom}–${validTo})`);
        console.error(error.message);
        return error;
    }
    
    // 2. Check the subject name (optional, based on actual requirements).
    // const expectedSubject = 'CN=*.mqtt.tencenttdmq.com';
    // if (!cert.subject.CN || !cert.subject.CN.includes('mqtt.tencenttdmq.com')) {
    //     const error = new Error(`Certificate verification failed: Subject mismatch (actual: ${cert.subject.CN})`);
    //     console.error(error.message);
    //     return error;
    // }
    
    // 3. Use the default certificate chain for verification.
    const err = tls.checkServerIdentity(host, cert);
    if (err) {
        console.error('Certificate verification failed:', err.message);
        return err;
    }
    
    console.log('Certificate verification passed');
    return undefined;
}

// Create a client and connect.
const client = mqtt.connect(serverUri, options);

// Connection successful
client.on('connect', async () => {
    console.log('Connected (TLS encrypted)');

    try {
        // 2. Subscribe
        for (let i = 0; i < topicFilters.length; i++) {
            await new Promise((resolve, reject) => {
                client.subscribe(topicFilters[i], { qos: qos[i] }, (err) => {
                    if (err) reject(err);
                    else resolve();
                });
            });
        }
        console.log('Subscribed');

        // 3. Publish
        for (let i = 1; i <= 16; i++) {
            await new Promise((resolve, reject) => {
                client.publish(pubTopic, `Message #${i}`, { qos: 1 }, (err) => {
                    if (err) reject(err);
                    else resolve();
                });
            });
            await new Promise(resolve => setTimeout(resolve, 500));
        }
        console.log('Published');

        // 4. Wait to receive
        await new Promise(resolve => setTimeout(resolve, 2000));

        // 5. Disconnect
        client.end();
        console.log('Disconnected');
    } catch (error) {
        console.error('Error:', error.message);
        client.end();
    }
});

// Message receiving and processing
client.on('message', (topic, message) => {
    console.log(`Received message: ${topic} -> ${message.toString()}`);
});

// Error handling
client.on('error', (error) => {
    console.error('Error:', error.message);
});

const mqtt = require('mqtt');

/**
 * MQTT 3.1.1 TCP Connection Example
 */

// ============ Connection Configuration ============
const serverUri = 'mqtt://mqtt-xxx.mqtt.tencenttdmq.com:1883';
const clientId = 'QuickStart';
const username = 'YOUR_USERNAME';
const password = 'YOUR_PASSWORD';
const pubTopic = 'home/test';
const topicFilters = ['home/test', 'home/#', 'home/+'];
const qos = [1, 1, 1];

// Configure connection options.
const options = {
    clientId: clientId,
    username: username,
    password: password,
    protocolVersion: 4,  // MQTT 3.1.1
    clean: true,
    reconnectPeriod: 0,  // Disable automatic reconnection.
};

// Create a client and connect.
const client = mqtt.connect(serverUri, options);

// Connection successful
client.on('connect', async () => {
    console.log('Connected');

    try {
        // 2. Subscribe
        for (let i = 0; i < topicFilters.length; i++) {
            await new Promise((resolve, reject) => {
                client.subscribe(topicFilters[i], { qos: qos[i] }, (err) => {
                    if (err) reject(err);
                    else resolve();
                });
            });
        }
        console.log('Subscribed');

        // 3. Publish
        for (let i = 1; i <= 16; i++) {
            await new Promise((resolve, reject) => {
                client.publish(pubTopic, `Message #${i}`, { qos: 1 }, (err) => {
                    if (err) reject(err);
                    else resolve();
                });
            });
            await new Promise(resolve => setTimeout(resolve, 500));
        }
        console.log('Published');

        // 4. Wait to receive
        await new Promise(resolve => setTimeout(resolve, 2000));

        // 5. Disconnect
        client.end();
        console.log('Disconnected');
    } catch (error) {
        console.error('Error:', error.message);
        client.end();
    }
});

// Message receiving and processing
client.on('message', (topic, message) => {
    console.log(`Received message: ${topic} -> ${message.toString()}`);
});

// Error handling
client.on('error', (error) => {
    console.error('Error:', error.message);
});

const mqtt = require('mqtt');
const fs = require('fs');
const tls = require('tls');

/**
 * MQTT 3.1.1 TLS Encrypted Connection Example
 */

// ============ Connection Configuration ============
const serverUri = 'mqtts://mqtt-xxx.mqtt.tencenttdmq.com:8883';
const clientId = 'QuickStart';
const username = 'YOUR_USERNAME';
const password = 'YOUR_PASSWORD';
const pubTopic = 'home/test';
const topicFilters = ['home/test', 'home/#', 'home/+'];
const qos = [1, 1, 1];

// CA certificate path (optional, used to verify the server certificate)
const caCertPath = null; // e.g., '/path/to/ca.crt'

// Configure connection options (including TLS).
const options = {
    clientId: clientId,
    username: username,
    password: password,
    protocolVersion: 4,  // MQTT 3.1.1
    clean: true,
    reconnectPeriod: 0,  // Disable automatic reconnection.
    
    // TLS Configuration
    rejectUnauthorized: true,  // Production environment: Verify the server certificate
    
    // If a CA certificate is provided, load it.
    ca: caCertPath ? [fs.readFileSync(caCertPath)] : undefined,
    
    // Custom certificate verification
    checkServerIdentity: (host, cert) => {
        return validateServerCertificate(host, cert);
    }
};

/**
 * Verify the server certificate.
 */
function validateServerCertificate(host, cert) {
    // 1. Check the certificate validity period.
    const now = new Date();
    const validFrom = new Date(cert.valid_from);
    const validTo = new Date(cert.valid_to);
    
    if (now < validFrom || now > validTo) {
        const error = new Error(`Certificate verification failed: The certificate has expired or is not yet valid (validity period: ${validFrom}–${validTo})`);
        console.error(error.message);
        return error;
    }
    
    // 2. Check the topic name (optional, based on actual requirements).
    // const expectedSubject = 'CN=*.mqtt.tencenttdmq.com';
    // if (!cert.subject.CN || !cert.subject.CN.includes('mqtt.tencenttdmq.com')) {
    //     const error = new Error(`Certificate verification failed: Subject mismatch (actual: ${cert.subject.CN})`);
    //     console.error(error.message);
    //     return error;
    // }
    
    // 3. Use the default certificate chain for verification.
    const err = tls.checkServerIdentity(host, cert);
    if (err) {
        console.error('Certificate verification failed:', err.message);
        return err;
    }
    
    console.log('Certificate verification passed');
    return undefined;
}

// Create a client and connect.
const client = mqtt.connect(serverUri, options);

// Connection successful
client.on('connect', async () => {
    console.log('Connected (TLS encrypted)');

    try {
        // 2. Subscribe
        for (let i = 0; i < topicFilters.length; i++) {
            await new Promise((resolve, reject) => {
                client.subscribe(topicFilters[i], { qos: qos[i] }, (err) => {
                    if (err) reject(err);
                    else resolve();
                });
            });
        }
        console.log('Subscribed');

        // 3. Publish
        for (let i = 1; i <= 16; i++) {
            await new Promise((resolve, reject) => {
                client.publish(pubTopic, `Message #${i}`, { qos: 1 }, (err) => {
                    if (err) reject(err);
                    else resolve();
                });
            });
            await new Promise(resolve => setTimeout(resolve, 500));
        }
        console.log('Published');

        // 4. Wait to receive
        await new Promise(resolve => setTimeout(resolve, 2000));

        // 5. Disconnect
        client.end();
        console.log('Disconnected');
    } catch (error) {
        console.error('Error:', error.message);
        client.end();
    }
});

// Message receiving and processing
client.on('message', (topic, message) => {
    console.log(`Received message: ${topic} -> ${message.toString()}`);
});

// Error handling
client.on('error', (error) => {
    console.error('Error:', error.message);
});



Parameter Description

Parameter
Description
topic
First-level MQTT topic, which can be copied from the Topic page on the cluster details page in the console.

connectUrl
Broker connection address, which can be copied from the Basic Information > Access Information section of the target cluster in the console, as shown below. Format: mqtt-xxx-gz.mqtt.qcloud.tencenttdmq.com:1883.

clientId
Client ID, which can be obtained from the Client Management page on the cluster details page in the console.

username
Connection username, which can be copied from the Authentication Management page on the cluster details page in the console.

password
Password matching the connection username, which can be copied from the Authentication Management page on the cluster details page in the console.

Previous Topic: C SDKNext Topic: Go SDK

Help and Support

Was this page helpful?

Help us improve! Rate your documentation experience in 5 mins.

Feedback