Permission denied when trying to update flake.lock

[Yucklys]

I put my flake.nix under /etc/nixos, as this is where the sudo nixos-rebuild switch default to. However, when I try to update the flake inputs by nh os switch --update, it successfully pulls the updates, but failed to update the flake.lock file due to permission denied. I have to manually update the flake inputs before I run this command. I think nh should ask for sudo permission to update the lock, as /etc/nixos/flake.nix is a common place that people will store their flake files.

[viperML]

nh doesn't run nix as root, only the activation scripts

[Yucklys]

I just want to know if this is the intended behavior, as it requires another command to upgrade. I write a wrapper for the commands and now it work perfectly.

[viperML]

It's weird behaviour nonetheless

[painsucker6k]

Same issue.

[painsucker6k]

nh doesn't run nix as root, only the activation scripts

I'm guessing that's the issue, as flakes are updated by the nix command? I'm not that experienced in nix, so excuse me if I'm wrong.

[viperML]

I know the issue but not the cleanest way to handle it. And my NixOS flake is not owned by root, so I don't need to fix this immediately

[painsucker6k]

So the temporary fix is changing the ownership of flake.nix and flake.lock?

[viperML]

I'd say not using nh's --update is the correct way

[different-name]

I am also struggling with this, nh os switch fails whenever I update my flake inputs, shouldn't nh ask for sudo like it does at other times it is required?

[viperML]

No, because I want to keep the evaluation apart from root

[different-name]

Do you suggest permanently changing ownership then?

[viperML]

Running nix flake update as the same user that owns the flake

[gepbird]

I have a similar issue: using agenix the quick and dirty way and putting a builtins.readFile config.age.secrets.foo.path in the config, I get a permission error: error: opening file '/run/agenix/foo': Permission denied

And sudo -E nh os switch doesn't work: Don't run nh os as root. I will call sudo internally as needed. Whats the reason for this sudo check?

[viperML]

Well readFile secret is certainly a usecase I want to block, so nh was working as intended.

Edit: + if anything, nix would not let you read files outside the flake because of the evaluation-time sandbox.

[darshmashru]

Maybe try this? Worked for me.

 sudo chown <user_name> ../flake.lock 

[Yucklys]

Maybe try this? Worked for me.

 sudo chown <user_name> ../flake.lock 

~Change ownership did let nh to access flake, but it didn't use cachix stores correctly. I suppose it is because it is using the cachix setting in the user directory.~

Edit: Thanks for your help! Find out it was a mistake with my cachix setup. After fixing the cache, I can update flake directly with nh now. Wonder why I never thought about this for months. The initial issue for me is solved, but I notice there is other person having issue with file permission too. So I will keep this issue open for now. Feel free to close it as you need.