PodVersion Platforms License Swift version Coverage Status

MQTT v3.1.1 client library for iOS/macOS/tvOS written with Swift 5


Build with Xcode 11.1 / Swift 5.1



Install using CocoaPods by adding this line to your Podfile:

use_frameworks! # Add this if you are targeting iOS 8+ or using Swift
pod 'CocoaMQTT'  

Then, run the following command:

$ pod install


Install using Carthage by adding the following lines to your Cartfile:

github "emqx/CocoaMQTT" "master"

Then, run the following command:

$ carthage update --platform iOS,macOS,tvOS

Last if you’re building for OS X:

  • On your application targets “General” settings tab, in the “Embedded Binaries” section, drag and drop CocoaMQTT.framework from the Carthage/Build/Mac folder on disk.

If you’re building for iOS, tvOS:

  • On your application targets “General” settings tab, in the “Linked Frameworks and Libraries” section, drag and drop each framework you want to use from the Carthage/Build folder on disk.

  • On your application targets “Build Phases” settings tab, click the “+” icon and choose “New Run Script Phase”. Create a Run Script with the following contents:

    /usr/local/bin/carthage copy-frameworks
  • and add the paths to the frameworks you want to use under “Input Files”, e.g.:



Create a client to connect MQTT broker:

let clientID = "CocoaMQTT-" + String(ProcessInfo().processIdentifier)
let mqtt = CocoaMQTT(clientID: clientID, host: "localhost", port: 1883)
mqtt.username = "test"
mqtt.password = "public"
mqtt.willMessage = CocoaMQTTWill(topic: "/will", message: "dieout")
mqtt.keepAlive = 60
mqtt.delegate = self

Now you can use closures instead of CocoaMQTTDelegate:

mqtt.didReceiveMessage = { mqtt, message, id in
	print("Message received in topic \(message.topic) with payload \(message.string!)")           

SSL Secure

One-way certification

No certificate is required locally. If you want to trust all untrust CA certificates, you can do this:

mqtt.allowUntrustCACertificate = true

Two-way certification

Need a .p12 file which is generated by a public key file and a private key file. You can generate the p12 file in the terminal:

openssl pkcs12 -export -clcerts -in client-cert.pem -inkey client-key.pem -out client.p12

MQTT over Websocket

In the 1.3.0, The CocoaMQTT has supported to connect to MQTT Broker by Websocket.

If you integrated by CocoaPods, you need to modify you Podfile like the followings and execute pod install again:


target 'Example' do
    pod 'CocoaMQTT/WebSockets', '1.3.0-rc.2'

Then, Create a MQTT instance over Websocket:

let websocket = CocoaMQTTWebSocket(uri: "/mqtt")
let mqtt = CocoaMQTT(clientID: clientID, host: host, port: 8083, socket: websocket)

// ...

_ = mqtt.connect()

If you want to add additional custom header to the connection, you can use the following:

let websocket = CocoaMQTTWebSocket(uri: "/mqtt")
websocket.headers = [
            "x-api-key": "value"
        websocket.enableSSL = true

let mqtt = CocoaMQTT(clientID: clientID, host: host, port: 8083, socket: websocket)

// ...

_ = mqtt.connect()

Example App

You can follow the Example App to learn how to use it. But we need to make the Example App works fisrt:

$ cd Examples

$ pod install

Then, open the Example.xcworkspace/ by Xcode and start it!


These third-party functions are used:


MIT License (see LICENSE)