Ruby
There currently is support to bundle applications that are packaged as Ruby gems. The utility "bundix" allows you to write a Gemfile, let bundler create a Gemfile.lock, and then convert
this into a nix expression that contains all Gem dependencies automatically.
For example, to package sensu, we did:
Gemfile
source 'https://rubygems.org'
gem 'sensu'
$ nix-shell -p bundler --command "bundler package --path /tmp/vendor/bundle"
$ $(nix-build '' -A bundix)/bin/bundix
$ cat > default.nix
{ lib, bundlerEnv, ruby }:
bundlerEnv rec {
name = "sensu-${version}";
version = (import gemset).sensu.version;
inherit ruby;
# expects Gemfile, Gemfile.lock and gemset.nix in the same directory
gemdir = ./.;
meta = with lib; {
description = "A monitoring framework that aims to be simple, malleable, and scalable";
homepage = http://sensuapp.org/;
license = with licenses; mit;
maintainers = with maintainers; [ theuni ];
platforms = platforms.unix;
};
}]]>
Please check in the Gemfile, Gemfile.lock and the gemset.nix so future updates can be run easily.
Resulting derivations also have two helpful items, env and wrapper. The first one allows one to quickly drop into
nix-shell with the specified environment present. E.g. nix-shell -A sensu.env would give you an environment with Ruby preset
so it has all the libraries necessary for sensu in its paths. The second one can be used to make derivations from custom Ruby scripts which have
Gemfiles with their dependencies specified. It is a derivation with ruby wrapped so it can find all the needed dependencies.
For example, to make a derivation my-script for a my-script.rb (which should be placed in bin) you should
run bundix as specified above and then use bundlerEnv lile this: