ads' corner

A while ago I integrated DWD warnings (Deutscher Wetterdienst) into our home automation system, and receive severe weather notifications ever since then. That works quite good, but it was missing a weblink with more details - or if you want to forward the warning to someone it would be useful to have a link to the warning as well. The DWD binding does not provide that piece of information, but it is easy enough to add - or so I thought.

The "Deutscher Wetterdienst" DWD (German Weather Service) provices a service which sends out alarms for upcoming events, like heavy rain, storm, blizzard, strong winds ect. This service is only available for Germany. And it has a binding for openHAB. Time to integrate this, activate a number of regions I'm interested in, and send notifications to our mobile phones.

At this point I'm really happy that I deploy my openHAB with Ansible, I can use the Template module and loop over the Items, Things and Rules.

The Binding can "track" multiple regions, so called Cell IDs. I'm interested in 4 different Cells (the list is available here), your mileage might vary. For each reagion there can be multiple messages - and although every single example I found only assumes there is only one message (warningCount=1), I already had a situation where a Cell had two warnings. That information likely goes missing if you set warningCount to 1. Given how much configuration overhead it is when you add more channels, I can understand why most examples stay at "1" for warningCount. Doubling the number doubles the number of Items (12 -> 24). However since I deploy everything in a template, that's not a problem here.

I started this with a generous warningCount=5 - and in my templates I just loop from 1 to 5, and over every Cell, and generate all the necessary Things and Rules for every channel.

Ok, the details:

A while ago I upgraded openHAB from version 2.4 to 2.5. That comes with the usual share of problems, but eventually I got it working.

For an unrelated project I wanted to use the OpenWeatherMap setup I have to improve the daily weather forecast with icons.

The binding provices ids for the current weather condition and the current weather icon. That can be used to load the icon from the OWM website. Went to my setup and added two new Items:

String	homeCurrentConditionID	"Current condition ID [%s]"	{ channel="openweathermap:weather-and-forecast:home:current#condition-id" }
String	homeCurrentIconID	"Current icon ID [%s]"		{ channel="openweathermap:weather-and-forecast:home:current#icon-id" }

Used Ansible to deploy everything to the Raspberry running openHAB. And then wondered because only the "homeCurrentConditionID" item came online, not the "homeCurrentIconID". After searching around and browsing the community forum, it turns out that the "icon-id" channel is new in 2.5, and will not automatically installed if the OpenWeatherMap binding was already used in 2.4. WT* ...

One has to remove all the OWM things ("openweathermap:weather-api:home" and "openweathermap:weather-and-forecast:home") and reinstall everything, in order to get the new channels working. That is really unexpected, and not user friendly.

After mumbling a while over my options I went ahead, created a new backup, and then removed the two items. One did get stuck along the way, a long Java trace appeared in the logfile, and I had to force remove it. Then - for good measueres - I also uninstalled the binding, and restarted openHAB.

Afterwards I re-deployed my Ansible Playbook, which installs the binding, takes care of the binding configuration, and adds the Things again. After everything came online, the homeCurrentIconID Item is also populated. Why is everything in openHAB so complicated?

As mentioned in my previous openHAB blog post: it seems to be too much to ask to have a reliable and working display in the kitchen.

Another problem I found is that the weather data occasionally does not update. Everything seems to work, no errors in the log, just no updated data. Of course this results in outdated weather info in the kitchen, and the threat that "someone" will buy a regular weather station and render my 7" Raspberry display useless.

After fighting with logs and debugging and not finding any real clue, I decided to tackle this problem from another angle, and regularly check if the weather data is up to date.

Don't you love it when things suddenly stop working?

In my openHAB installation I have a check which verifies that the weather data is up to date. Otherwise it restarts the openhab2 service. And this check stopped working ... Leaving the kitchen display not updated for a longer time. The same display where I expect the entire installation to "just work", and don't create so many different problems. Seems to be a hard problem to have an openHAB installation without any trouble ...

After setting up OpenWeatherMap in openHAB, I had another project on my list: send a forecast for the next day.

That is rather easy to do with a Cron rule.

Next item on my home automation todo list: weather, and forecast. No good system without that data!

After exploring the options which openHAB supports, I settled for OpenWeatherMap. Note: you need an account with OWM, the basic functionality is free, the paid options give you more and better forecast.

And of course, I install everything using Ansible, and can just repeat the entire installation if something does not work.

This setup is also used in a weather forecast for tomorrow.