Bug or intended behavior? MongoDB + Cockpit Docker fails to restore data after Docker restart

I spawned a cockpit instance using Docker and an external MongoDB instance. The application connects and I can create a singleton.

When I rebuild the docker container using the Dokku commandline the singleton is gone. However, during the creation process of the exact same singleton (name) with the exact same fields, the form fields are prefilled with the original content.

It is as if Redis or (cockpit itself?) fails to read the singleton from the DB.

I noticed this behavior running on a normal docker image as well as on a Dokku deploy system.

This problem has been solved today, it turns out the Volume was not set in the Dokku instance and for some reason there where permission issues using the storage in vanilla Docker.

While, now I went through the files manually, I know how it works, the documentation makes no real mention that content (singletons & collections) are stored in part in a DB and in part in the storage folder.

We might want to change the documentation to reflect that.