#AutoConnect CallBack function
- Use this function if you want to use autoconnect(and auto reconnect) facility
- This function is called whenever TCP connection is established (or re-established).
- This function can be used to connect your client to MQTT broker.
- Use only if you do not use Auto connect functionality.
- Optionally you can use username, password, WILL topic and WILL Message.
#OnConnect CallBack function
- This call back function is called when MQTT connection is established.
- You can call subscription and publish functions inside it (according to your need).
- This function can be used to publish messages to different topics.
- You can select QoS levels and RETAIN flag according to your need.
- This function can be used to subscribe messages from different topics.
OnMessage CallBack function
- This callback function is called when messages are received from subscribed topics
- Topic, TopicLength, Message, MessageLength are the arguments of OnMessage callback function.
- Inside this, you can write your custom code.
- This function can be used to unsubscribe from a previously subscribed topic.
- This function can be used to disconnect your client from MQTT broker.
- return true when connection with mqtt brocker is existing
- You can specify your KeepAlive duration while initializing.
- Ping requests are sent and received automatically.
- QoS 0,1,2