Home Automation System - Checking TASMOTA firmware updates with OpenHAB v.2

A little post about managing notifications about new TASMOTA firmware versions for SONOFF devices on OpenHAB v.2

As we already know reading the official TASMOTA documentation (https://github.com/arendst/Sonoff-Tasmota/wiki/Upgrade#firmware-binary-sources), @smadds user manages a public MQTT broker "sonoff.maddox.co.uk:1883", where he publishes the last version number of the TASMOTA firmware using topic sonoff-version.

So, in my setup, I just added an "item" linked to this value, through MQTT and then published it on my sitemap.

First thing to do was create a new MQTT connection (called sonoffmaddox-mqtt) to the @smadds broker, appending the following lines to the /etc/openhab2/services/mqtt.cfg file

sonoffmaddox-mqtt.url=tcp://sonoff.maddox.co.uk:1883
sonoffmaddox-mqtt.clientId=
sonoffmaddox-mqtt.user=
sonoffmaddox-mqtt.pwd=
sonoffmaddox-mqtt.qos=0
sonoffmaddox-mqtt.retain=true

Then I created a new file called general.items, in the /etc/openhab2/items folder, in which I wrote down the following line:

String      SonoffTasmotaVersion      "SONOFF Tasmota Version [%s]"     <settings>
{mqtt="<[sonoffmaddox-mqtt:sonoff-version:state:default]"}

My item is called SonoffTasmotaVersion, its type is "String" and it is linked to the mqtt connection called sonoffmaddox-mqtt, topic sonoff-version. In this way, this item will be updated everytime someone will publish new messages on topic sonoff-version.

Last step: I added my new item to the sitemap, just to keep tracking of the last TASMOTA version.
So, I edited the /etc/openhab2/sitemaps/test.sitemap file, inserting, on the top, the item just created inside a frame called "general":

Frame label="General" {
    Text item=SonoffTasmotaVersion
}

Here is the result:

To be more useful, I created a new OpenHAB rule just to be notified every time the TASMOTA version will be updated.

So, I created the /etc/openhab2/rules/checks.rules file, and wrote down the following lines:

rule "tasmota version check"
when
Item SonoffTasmotaVersion changed
then

logInfo("rules", "New Tasmota Version " + SonoffTasmotaVersion.state)

sendNotification([user_to_be_notified], "New Tasmota Version " + SonoffTasmotaVersion.state)

end

The sendNotification function sends a notification to the specified user; this notification reaches the mobile devices where the OpenHAB App is installed and linked to the OpenHAB cloud (MyOpenHAB). Its configuration is very simple, just following the official guide: http://docs.openhab.org/addons/io/openhabcloud/readme.html

Now I have to wait for the next TASMOTA update just to check that all is working as expected.