Understanding the CocoaMQTT client in Swift 3

The CocoaMQTT client is very easy to use. First, it is necessary to import CocoaMQTT, create an instance of the CocoaMQTT class, specify the MQTT connection configuration values, and indicate an instance of a class that conforms to the CocoaMQTTDelegate protocol. We can call the methods for the created CocoaMQTT instance to subscribe to topics and publish messages.

Let's take a look at the code that declares the CocoaMQTTDelegate protocol:

@objc public protocol CocoaMQTTDelegate {
    func mqtt(_ mqtt: CocoaMQTT, didConnect host: String, port: Int)
    func mqtt(_ mqtt: CocoaMQTT, didConnectAck ack: CocoaMQTTConnAck)
    func mqtt(_ mqtt: CocoaMQTT, didPublishMessage message: CocoaMQTTMessage, id: UInt16)
    func mqtt(_ mqtt: CocoaMQTT, didPublishAck id: UInt16)
    func mqtt(_ mqtt: CocoaMQTT, didReceiveMessage message: CocoaMQTTMessage, id: UInt16 )
    func mqtt(_ mqtt: CocoaMQTT, didSubscribeTopic topic: String)
    func mqtt(_ mqtt: CocoaMQTT...