example application: add InfluxDB support

station_cfg = {}

dofile("config.lua")

publishing_mqtt = false

publishing_http = false

delayed_restart = tmr.create()

watchdog = tmr.create()

push_timer = tmr.create()

chip_id = node.chipid()

chip_id = string.format("%06X", node.chipid())

device_id = "esp8266_" .. chip_id

mqtt_prefix = "sensor/" .. device_id

mqttclient = mqtt.Client(device_id, 120)

dofile("config.lua")

print("ESP8266 " .. chip_id)

i2c.setup(0, 2, 1, i2c.SLOW)

function log_restart()

	print("Network error " .. wifi.sta.status() .. ". Restarting in 20 seconds.")

	delayed_restart:start()

	print("Network error " .. wifi.sta.status())

end

function setup_client()

	if not scd4x.start() then

		print("SCD4x initialization error")

	end

	publishing = true

	publishing_mqtt = true

	mqttclient:publish(mqtt_prefix .. "/state", "online", 0, 1, function(client)

		publishing = false

		publishing_mqtt = false

		push_timer:start()

		push_data()

	end)

end

function connect_mqtt()

	print("IP address: " .. wifi.sta.getip())

	print("Connecting to MQTT " .. mqtt_host)

	delayed_restart:stop()

	mqttclient:on("connect", hass_register)

	mqttclient:on("offline", log_restart)

	mqttclient:lwt(mqtt_prefix .. "/state", "offline", 0, 1)

		print("SCD4x error")

	else

		local json_str = string.format('{"co2_ppm": %d, "temperature_degc": %d.%d, "humidity_relpercent": %d.%d, "rssi_dbm": %d}', co2, raw_temp/65536 - 45, (raw_temp%65536)/6554, raw_humi/65536, (raw_humi%65536)/6554, wifi.sta.getrssi())

		if not publishing then

			publishing = true

		local influx_str = string.format("co2_ppm=%d,temperature_degc=%d.%d,humidity_relpercent=%d.%d", co2, raw_temp/65536 - 45, (raw_temp%65536)/6554, raw_humi/65536, (raw_humi%65536)/6554)

		if not publishing_mqtt then

			publishing_mqtt = true

			watchdog:start(true)

			gpio.write(ledpin, 0)

			mqttclient:publish(mqtt_prefix .. "/data", json_str, 0, 0, function(client)

				publishing = false

				publishing_mqtt = false

				if influx_url and influx_attr and influx_str then

					publish_influx(influx_str)

				else

					gpio.write(ledpin, 1)

					collectgarbage()

				end

			end)

		end

	end

	push_timer:start()

end

function publish_influx(payload)

	if not publishing_http then

		publishing_http = true

		http.post(influx_url, influx_header, "scd4x" .. influx_attr .. " " .. payload, function(code, data)

			publishing_http = false

			gpio.write(ledpin, 1)

			collectgarbage()

		end)

	end

end

function hass_register()

	local hass_device = string.format('{"connections":[["mac","%s"]],"identifiers":["%s"],"model":"ESP8266","name":"ESP8266 with SCD4x","manufacturer":"DIY"}', wifi.sta.getmac(), device_id)

	local hass_device = string.format('{"connections":[["mac","%s"]],"identifiers":["%s"],"model":"ESP8266 + SCD4x","name":"SCD4x %s","manufacturer":"derf"}', wifi.sta.getmac(), device_id, chip_id)

	local hass_entity_base = string.format('"device":%s,"state_topic":"%s/data","expire_after":600', hass_device, mqtt_prefix)

	local hass_co2 = string.format('{%s,"name":"CO₂","object_id":"%s_co2","unique_id":"%s_co2","device_class":"carbon_dioxide","unit_of_measurement":"ppm","value_template":"{{value_json.co2_ppm}}"}', hass_entity_base, device_id, device_id)

	local hass_temp = string.format('{%s,"name":"Temperature","object_id":"%s_temperature","unique_id":"%s_temperature","device_class":"temperature","unit_of_measurement":"°c","value_template":"{{value_json.temperature_degc}}"}', hass_entity_base, device_id, device_id)

	end)

end

delayed_restart:register(20 * 1000, tmr.ALARM_SINGLE, node.restart)

push_timer:register(20 * 1000, tmr.ALARM_SEMI, push_data)

watchdog:register(180 * 1000, tmr.ALARM_SEMI, node.restart)

push_timer:register(20 * 1000, tmr.ALARM_AUTO, push_data)

watchdog:start()

connect_wifi()