Strav's blog

Here are a number of posts about the Arduino esp8266 and MQTT.

ESP8266: Connecting to MQTT broker
How To Use Basic MQTT on Arduino
How to use ArduinoJson with PubSubClient
Callback function and MQTT Arduino client
Strings, bytes, char arrays MQTT arghgh
What is the best MQTT Client for Pub and Sub?

On a related note - this discusses converting byte* to char[]

Is it possible to convert a byte* to char[]?
convert byte array into string