sroebert/mqtt-nio

Installation

Use the SPM string to easily include the dependendency in your Package.swift file.

.package(url: "https://github.com/sroebert/mqtt-nio.git", from: "2.0.0")

Supported Platforms

MQTTNIO supports the following platforms:

• Ubuntu 18.04+
• macOS 10.9+, iOS 7+, tvOS 12+ or watchOS 6+

Dependencies

This package has four dependencies:

• apple/swift-nio for IO.
• apple/swift-nio-ssl for TLS.
• apple/swift-nio-transport-services to support Apple platforms as first-class citizens.
• apple/swift-log for logging.

This package has no additional system dependencies.

Usage

Create Client and Connect

let client = MQTTClient(
    configuration: .init(
        target: .host("127.0.0.1", port: 1883)
    ),
    eventLoopGroupProvider: .createNew
)
client.connect()

The client automatically reconnects when failing to connect or when disconnected from the broker.

Connect to an MQTT 3.1.1 broker

let client = MQTTClient(
    configuration: .init(
        target: .host("127.0.0.1", port: 1883),
        protocolVersion: .version3_1_1
    ),
    eventLoopGroupProvider: .createNew
)
client.connect()

Connect using a URL

let client = MQTTClient(configuration: .init(url: URL(string: "mqtts://test.mosquitto.org")!))
client.connect()

let client = MQTTClient(configuration: .init(url: URL(string: "wss://test.mosquitto.org:8081")!))
client.connect()

Subscribe

client.subscribe(to: "some/topic")

Unsubscribe

client.unsubscribe(from: "some/topic")

Publish

client.publish("Hello World!", to: "some/topic", qos: .exactlyOnce)

client.publish("Hello World!", "some/topic")

client.publish("Hello World!", to: "some/topic", retain: true)

Receive callbacks to know when the client connects/disconnects and receives messages.

client.whenConnected { response in
    print("Connected, is session present: \(response.isSessionPresent)")
}

client.whenDisconnected { reason in
    print("Disconnected: \(reason)")
}

client.whenMessage { message in
    print("Received: \(message)")
}

For platforms where the Combine framework is available, it is also possible to subscribe to publishers.

let cancellable = client.connectPublisher
    .sink { response in
        print("Connected, is session present: \(response.isSessionPresent)")
    }

let cancellable = client.disconnectPublisher
    .sink { reason in
        print("Disconnected: \(reason)")
    }

let cancellable1 = client.messagePublisher
    .sink { message in
        print("Received: \(message)")
    }
let cancellable2 = client.messagePublisher(forTopic: "some/topic")
    .sink { message in
        print("Received: \(message)")
    }

async/await

On platforms where async await is supported, it is possible to use async functions on MQTTClient.

try await client.publish("Hello World!", "some/topic")

for await message in client.messages {
    print("Received: \(message)")
}

Unit Tests

To easily run the tests locally, first generate self signed certificates followed by running docker-compose to setup the needed MQTT broker containers.

./mosquitto/certs/generate.sh
docker compose up

Package Metadata

Repository: sroebert/mqtt-nio

Default branch: main

README: README.md