Weird MAP-transformation file failures

Hi all, I am setting up openHAB 3.4.2 on a RPi 4. But I experience some weirdness when using .map files in /etc/openhab/transform.

As I did for my Javascript transformations, I created a separate folder ‘mappings’ for mapping-files. But no matter how I defined the path (MAP:/mappings/ or MAP:mappings/ or MAP:/mappings/ etc.) it failed reading it:

Blockquote [WARN ] [t.generic.ChannelStateTransformation] - Executing the MAP-transformation failed: Could not find configuration ‘/mappings/’ or failed to parse it.

(changing permissions/owner made no difference)

Then I moved the file one folder back to the ‘transform’ folder and use, but still no success.

Created a new file and set does work allright.
But a new file with the name ‘’ fails…

So my questions are:

  1. Is it true that subfolders for map-transformation files are not allowed?
  2. Or how should it be set then?
  3. Are there restrictions for filenames in this particular setting?


Subfolders are not supported.

Regarding file-naming: anything should be fine. Are you sure that you got the case right? Matching is case-sensitive.

Thanks Jan for clearing!

(yes filename spelled/cased correctly, thought it was due to length or something, but will try some new better filenames again)

Maybe it helps other users. My renaming/moving caused an owner/group change on the files. Having it reset to root/root (chown + chgrp) was the final solution.

1 Like

If you’re using openHABian, there’s a menu item in openhabian-config to reset file permissions.