mqtt-button.lua

dofile("settings.lua")

myMACAddress = wifi.sta.getmac()

buttonUser = 1
buttonTopic = "buttons/" .. myMACAddress


wifi.setmode(wifi.STATION)
wifi.sta.config(wifiSSID, wifiPassword)
wifi.sta.connect()

-- Debounce code based on
-- https://gist.github.com/marcelstoer/59563e791effa4acb65f

function debounce (func)
    local last = 0
    local delay = 200 * 1000 -- 200ms * 1000 as tmr.now() has μs resolution

    return function (...)
        local now = tmr.now()
        local delta = now - last
        if delta < 0 then delta = delta + 2147483647 end; -- proposed because of delta rolling over, https://github.com/hackhitchin/esp8266-co-uk/issues/2
        if delta < delay then return end;

        last = now
        return func(...)
    end
end

local function buttonUserCallback(level)
    mqttClient:publish(buttonTopic, 1 - level, 0, 0)
end

local function wifiConnected()
    ssid, password, bssid_set, bssid = wifi.sta.getconfig()
    ip, netmask, gateway = wifi.sta.getip()
    print("Connected to " .. ssid .. " with ip address " .. ip)

    mqttClient = mqtt.Client("myclient", 120, mqttUser, mqttPassword)
    
    mqttClient:on("connect", function(client)
        print ("MQTT connected")
	print("Publishing button presses at '" .. buttonTopic .. "'")

        gpio.mode(buttonUser, gpio.INT, gpio.PULLUP)
        gpio.trig(buttonUser, "both", debounce(buttonUserCallback))
    end)
    
    mqttClient:on("offline", function(client)
        print ("MQTT offline")
    end)

    mqttClient:connect(mqttServerAddress, mqttPort, 0, 1)
end

local function checkConnection()
    if (1 == wifi.sta.status()) then
        print("Not connected")
    else
        tmr.stop(1)
        wifiConnected()
    end
end

tmr.alarm(1,1000, 1, checkConnection)