The overwriteprotocol option can be used to force Nextcloud to generate
URLs with the given protocol. This is useful for instances behind
reverse proxies that serve Nextcloud with HTTPS.
In this case Nextcloud can't determine the proper protocol and it needs
to be configured manually.
NixOS currently defaults services.nginx.package to
nginxStable. Including configuration files from nginxMainline could
potentially cause incompatible configuration.
Part of #49783. NextCloud tracks in its `config.php` the application's
state which makes it hard for the module to modify configurations during
upgrades.
It will take time until the issue is properly fixed, therefore we
decided to warn about this in the manual.
This PR addresses two things:
* Adding a basic example for nextcloud. I figured it to be helpful to
add some basic usage instructions when adding a new manual entry.
Advanced documentation may follow later.
For now this document actively links to the service options, so users
are guided to the remaining options that can be helpful in certain
cases.
* Add a warning about upgrades and manual changes in
`/var/lib/nextcloud`. This will be fixed in the future, but it's
definetely helpful to document the current issues in the manual (as
proposed in https://github.com/NixOS/nixpkgs/issues/49783#issuecomment-439691127).
