Nixos-rebuild switch and fetchurl of local file

Help
1

I have a custom theme for slim in a local file, which was working but when I went to upgrade it broke:

# nixos-rebuild switch
…
trying file:///etc/nixos/cfg/rsrc/nixos-slim-theme-dark.tar.gz
curl: (37) Couldn’t open file /etc/nixos/cfg/rsrc/nixos-slim-theme-dark.tar.gz
error: cannot download nixos-slim-theme-dark.tar.gz from any mirror
…

Yet running curl from the command line works:

# curl file:///etc/nixos/cfg/rsrc/nixos-slim-theme-dark.tar.gz > /tmp/foo

Here is the relevant part of my configuration.nix:

  displayManager.slim = {
    enable = true;
    theme = pkgs.fetchurl {
      url    = "file:///etc/nixos/cfg/rsrc/nixos-slim-theme-dark.tar.gz";
      sha256 = "1ac8xhvw5gv95mql7684iimqrbvxwblpiwis21v3lw3l34pyrf1n";
    };
  };

What should I be doing so that this works first time every time?

1 Like
2

I think it should be simply theme = /path/file.tar.gz

3

But anyway, if the build is performed by nix daemon, this file won’t be available to the deamon. To make it so it should be ${/path/file.tar.gz}.

4

The ${...} probably isn’t necessary. Just using the path literal syntax should cause it to be copied to the store, rather than refer to the original path.

5

It depends (whether it’s captured in some other context), ${...} will capture it right here for sure.

6

Yea, that’s why I only said “probably” :stuck_out_tongue: The only way that wouldn’t be the case is if someone used toString for some reason, which isn’t common.

7

Thank you all. I used the simplest approach of just specifying the path as a path literal as suggested by @ip1981. That worked.