openhab/freifunk

Freifunk

Monitor some parameters like online status and client count of Freifunk routers

Typically Freifunk routers are not connected to the local (home) network. So it cannot be pinged to verify that it is online. Also successfully pinging the devices is not telling you anything about the status in the Freifunk network. So I access a JSON file provided by the Freifunk network, in my case Freifunk Stuttgart. You might need to adjust it to your needs as I do not have any information how other Freifunk communities provide data.

First you need to put the freifunk bash script somewhere where you can access it. I created a directory /home/openhabian/scripts for scripts like this one. Then you need to create a working directory for this script, in my case it is /home/openhabian/freifunk.

Use cron to get new data every minute, example:

*/1 *    * * *   root    /home/openhabian/scripts/freifunk > /dev/null 2>&1

Then create three new things in Paper UI. Use the Exec binding and enter the following parameters:

Thing for online status:

• Name: freifunk_isonline
• Command: cat /home/openhabian/freifunk/freifunk
• Transform: JS(freifunk_isonline.js)
• Interval: 60

Thing for client count:

• Name: freifunk_clientcount
• Command: cat /home/openhabian/freifunk/freifunk
• Transform: JS(freifunk_clientcount.js)
• Interval: 60

When was the last change of the JSON data downloaded:

• Name: freifunk_updatedat
• Command: cat /home/openhabian/freifunk/freifunk
• Transform: JS(freifunk_updatedat.js)
• Interval: 60

The new things get an id like exec:command:a1b2c3d4 which you then need to enter in the items created through the freifunk.items file.

• freifunk: Put the bash script into /home/openhabian/scripts (or somewhere else you like) and chmod 755 it to make it executable. Modify/replace the MAC address to the MAC address of the Freifunk router you want to monitor.
• freifunk.items: Put this file into your /etc/openhab2/items directory and modify it for your specific setup. Maybe everything suits your needs, but you need to match the command ids in the channel command to the things you created earlier in Paper UI.
• freifunk.map: Put this file into your /etc/openhab2/transform directory.
• **freifunk_*.js**: Put these files into your */etc/openhab2/transform* directory.