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openHAB 2 comes with a Telegram binding which allows to run a Telgram Bot. This bot can both send messages to users and groups, and can receive commands and respond to them. That's useful: your home automation system can send all kind of details to your mobile phone.

For this to make it work it needs a couple things:

First of all a mobile phone with the Telegram app on it. You can either have the bot message you directly, but this only works for one person. Or you create a group, and have the bot send the messages to the group instead. Find out about the group ID here.

Then you need to create a Telegram Bot. Instructions are available here.

And everything needs to be hooked up in openHAB.

 

Continue reading "openHAB and Telegram Bot"

I really like to monitor things, to catch issues early on. In our home we have a couple ChromeCasts, both Audio and Video. They are all connected to the openHAB system, Once in a while they stop working, and need to be restarted (unplugged and plugged in again). Unfortunately you usually only find that out when you want to stream something, and wonder why either the ChromeCast does not show up in the device list, or does show up but does not accept the media.

Therefore I decided to monitor the devices in openHAB.

 

Continue reading "Monitor ChromeCast status in openHAB"

Recent openHAB versions come with a new HP Printer Binding, which is a big improvement over the more general IPP Binding for printers.

The new binding reads the data from two files which are provided by the printer:

• http://<printer>/DevMgmt/ProductUsageDyn.xml
• http://<printer>/DevMgmt/ProductStatusDyn.xml

Let's install that ...

 

Continue reading "openHAB and HP printer"

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?

The openHAB display in the kitchen is still the problem child. Occasionally it just stops, other times it does not refresh the HABpanel, even though it has a connection to the openHAB server. Then there is the problem with the network card in the Pi. And - ok, that's a server-side problem - occasionally the weather stops updating. All in all that's a lot of trouble for a display which is just supposed to run standalone.

In the latest iteration I looked into activating the integrated hardware watchdog in the Raspberry Pi. Checking the temperature it never goes above ~55°C celcius, even though the display is in an almost closed frame and can't exchange much heat with the environment. But nevertheless occasionally the Pi just halts, and stops operating.

 

Continue reading "Raspberry Pi watchdog for openHAB"

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.

 

Continue reading "openhab2: check if alive"

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 ...

 

Continue reading "Apache Karaf client in openHAB, and the "Session has been closed" error"

openHAB is a stream of pure joy when it comes to debugging. Especially when all I want is a small display in the kitchen, working autonomous and without the need to restart it all the time or login to fix issues.

The latest installment of that endeavor was a black screen in the browser, with no way to even get to the usual HABpanel controls. After some debugging, it turns out that the file "habpanel.config" (/var/lib/openhab2/config/org/openhab/habpanel.config) on the openHAB server was destroyed, or more accurate: shortened to 4829 bytes. Lucky me I have this file in my Ansible playbooks, and whenever there is a change, a copy of this file is fetched to my Ansible host. From there it goes into my backups, and I can restore a couple dozen versions back, if needed. So not all is bad, but still something is not working as expected. First I installed a copy of this file from my backups - but turns out shortly later the file is shortened again. Later I figured that the file is always shortened when the openHAB service restarts. This particular instance was still running openHAB 2.4, and I used this opportunity to upgrade to 2.5, test my Playbooks (and exclude the one config file from everything) and see if the problem persists. It does. Except that after upgrading to 2.5 the file is no longer shortened to 4829 bytes, but to 4875 bytes.

Every time that happens, the file ends somewhere in the middle of the HABpanel panel configuration - and naturally the HABpanel service can no longer read that file and shows a blank screen. I would wish that it rather shows an error message, or does something useful here, but oh well.

For a while (and mostly because I was busy with other tasks) I helped myself by changing the owner of "habpanel.config" and the directory this files lives in to "root:root". This threw a couple other errors into the logfile, but helped somewhat because the config file got no longer destroyed when the service restarted.

 

Continue reading "openHAB HABpanel configuration gets destroyed, HABpanel stays blank"

Previously I blogged about how the washing machine and the dryer are integrated into the openHAB home automation system.

For a while I had a standard "Dummy" widget in HABpanel, but that didn't look very nice, was very standard, and the different icons for different states don't really work. When I started integrating another Raspberry Pi with a touch screen (blog post to come), I refreshed the HABpanel, added another dashboard, and along the way I wrote a new "Template" widget for the washing machine and the dryer.

This project had a number of small goals:

1. Make the headline (the name) bigger - in the dummy it seems to be hardcoded, and very small
2. Use the proper icon for every Item state (running, finished, standby)
3. Change the background color of the widget according to the state of the Item

 

Continue reading "openHAB: widget with multiple different background colors"

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.

 

 

Continue reading "Weather Forecast in openHAB based on OpenWeatherMap, using Ansible"