Read-only chroot stores

[FRidh]

If I created store paths as user A with

nix run --store /tmp/localstore/ -f channel:nixos-17.09 python3 --command python3

and then want to run the exact same executable as user B

nix run --store /tmp/localstore/ -f channel:nixos-17.09 python3 --command python3
error: opening lock file '/tmp/localstore/nix/var/nix/db/big-lock': Permission denied

It would be nice to be able to use an existing chroot store made by another user.

I am aware it is possible to simply build the store elsewhere.

[FRidh]

I imagine this is caused by the downloading of the tarball channel. Therefore, I thought of using fetchTarball, which we would anyway use. Consider a default.nix:

with import (fetchTarball {
  url=https://github.com/NixOS/nixpkgs-channels/archive/b30c6d795035ad93932994cc28e909f0f6131070.tar.gz;
  sha256="0drdwi5w3sfivnbb2fmkrk829grlggr4r2n5mj4k1izvvf28yqmr";
}){};

python3

Running as user A:

nix run  --store /tmp/localstore -f default.nix --command python3
nix: src/libexpr/primops.cc:56: void nix::EvalState::realiseContext(const PathSet&): Assertion `store->isStorePath(ctx)' failed.
Aborted

$ nix --version
nix (Nix) 2.1pre6148_a4aac7f

[FRidh]

I guess it looks in the wrong store for the tarball?

[lheckemann]

That second bit looks related to #2085.

[catern]

Did you ever figure out how to do this? I have a significant use-case for read-only chroot stores (Nix stores held on a read-only network filesystem) so I'm strongly interested in figuring out how to make this work.

[stale]

I marked this as stale due to inactivity. → More info

[stale]

I closed this issue due to inactivity. → More info