Thanks, this is a good idea, but probably too much of a workaround for now and may be the plan B, but did get me thinking about using files as a semiphore to pass messages or requests to host.
So, I solved the problem by doing this:
- I wrote a bash script (watcher.sh) that watches a folder within the node-red docker volume (i.e. the host of node-red's /data/requests).
- Node-red writes files (requests) to that folder (/data/requests), either using the filename as the request indicator (placing a json request inside the file).
- The watcher.sh is notified of the new file, reads the filename as the request (or the json within the file), and performs the request.
- On completion, the watcher writes a confirmation file back to the node-red docker volume (/data/responses), either with a meaningful filename or containing a response json within the file.
I set the watcher.sh script up to run as a service, and ensured systemd had execute rights, and that the service auto-starts on boot. It works like a charm!
It is a great way to allow a container to request a host action (such as starting or stopping another docker container), or passing basic messages between co-located docker containers.
Thanks for the idea, it is very much appreciated.
