Nixpkgs: Package request: Gajim OMEMO

[lverns]

Issue description

OMEMO is a proposed end-to-end encryption scheme for XMPP that Gajim supports via a plugin. This plugin can be installed into user's home directories with Gajim's built-in plugin manager, but this does not work because the plugin cannot find the needed python modules.

01/05/2017 15:32:08 (E) gajim.plugin_system.omemo No module named google.protobuf
01/05/2017 15:32:08 (E) gajim.plugin_system.omemo No module named axolotl

I was able to get this working by placing

{
  packageOverrides = pkgs_: with pkgs_;
  {
     omemo = python27.withPackages (ps: with ps; [cryptography python-axolotl python-axolotl-gajimcurve25519 qrcode]);
  };
}

in ~/.nixpkgs/config.nix and running nix-env -iA nixpkgs.omemo. Finally, running PYTHONPATH="$HOME/.nix-profile/lib/python2.7/site-packages" gajim made the plugin usable.

In Debian, there is a nice package called gajim-omemo which allows the admin to install the plugin globally and the users need only _enable_ it via Gajim's plugin manager.

Adding such a package to nixpkgs could make using OMEMO much easier by removing the need for manually setting PYTHONPATH.

[Mic92]

In nixpkgs unstable there is the following build flag:

packageOverrides = pkgs: rec { 
     gajim = pkgs.gajim.override { enableOmemoPluginDependencies = true; };
}

and then everything works as expected.

[lverns]

That works pretty well, Thanks!

[Mic92]

the flag is now enabled by default: https://github.com/NixOS/nixpkgs/commit/98bcca88134be2934b4d4947d880954b46d3f06c