Multiple open issues related to permission

[icheered]

I noticed several people running into issues related to permissions, none of which are resolved. It might be a good idea to keep all communication in a single thread.

• Bootloop after updating from 2.0.15 to 2.0.21 (Stable) #556
• cannot create directory '/factorio/saves': Permission denied #555
• Error: filesystem error: copy_file "/factorio/temp/currently-playing/level.dat" failed: Permission denied #549
• Unable to run with Rootless Docker configuration. #496
• Docker for Windows Permissions Issues #501
• "Error Util.cpp:86: Operation not permitted" error when starting server on 1.1.107 #492
• 0.000 Error Util.cpp:83: filesystem error: status: Permission denied [/factorio/saves] #420

I noticed that purging the factoriotools image and re-pulling temporarily solved the permission issues. However after a while saving the game kept failing.

What I noticed is that even after running sudo chown -R 845:845 factorio_folder some files would be owned by user 100844 instead of 845 (run ls -la in the factorio folder and check the 3rd and 4th column). After chowning all files to user 100844 it does seem to work (for now).

I am running NixOS with docker-compose with docker in rootless mode.

[aSemy]

I've had a look, and have two observations. I'm not super up to date with Docker best practices, but the current Dockerfile has things which don't match my understanding. Maybe someone can explain, or maybe they could indicate a solution.

1. I see the Dockerfile manually creates a user, but didn't see a USER instruction in the Dockerfile. Isn't that required?

2. Is it necessary for the account that runs the Factorio file to chown all files?

   factorio-docker/docker/Dockerfile

   Line 89 in 19e5dc7

   && chown -R "$USER":"$GROUP" /opt/factorio /factorio

   I can imagine this would be necessary for a zero-config option, but I suspect that's causing issues with systems that have other ways of configuring permissions. On my machine I need my user to retain ownership of the files, but I do grant read/write permissions to the Factorio user.