Allen Nelson adnelson

Building nix with a repo over SSH

It's pretty simple to use a repo to aid the building of nix packages. You need:

Two machines, let's call them Builder and Repo.
Each machine has nix installed. Let's say that Repo has a nix installation owned by the user nix-repo, and Builder has one owned by nix-builder.
nix-builder is able to SSH into Repo as nix-repo.

Once you have this, to build a package on Builder using Repo:

	{
	### THIS WORKS
	# Fetches a package from a github repo.
	fetchRepo = {repo, name, version, sha256}:
	let
	github_token = builtins.getEnv "GITHUB_TOKEN";
	url = "https://api.github.com/repos/adnelson/${repo}/tarball/${name}%2F${version}";
	curlCmd = "curl --fail -fL -H 'Authorization: token ${github_token}'";
	in
	pkgs.stdenv.mkDerivation {

	# Function which takes a list of packages to install and creates a
	# tarball which contains the full list of dependencies of those paths,
	# and a script which will install them.
	#
	# For example, here's how you would create a tarball packaging up
	# python3 and nodejs:
	#
	#
	# let
	# pkgs = import <nixpkgs> {};

	class ParseError(Exception):
	pass

	# Each parser function should take a list of characters and an index
	# into that list, and return something that it parsed and a new index.

	def parse_optionally(parser):
	"""
	Parses or returns None
	"""

	def raise_msg(msg, path):
	if len(path) > 0:
	msg = 'At path {}: {}'.format('.'.join(path), msg)
	raise AssertionError(msg)

	def list_diff(list1, list2, path):
	if len(list1) != len(list2):
	raise_msg('List lengths differ: {} vs {}'
	.format(len(list1), len(list2)), path)
	for i, (obj1, obj2) in enumerate(zip(list1, list2)):

	nan = float('nan')
	def convert_nans(obj):
	if isinstance(obj, list):
	return [convert_nans(x) for x in obj]
	elif isinstance(obj, dict):
	return {k: convert_nans(v) for k, v in obj.iter()}
	elif obj is nan or obj is None:
	return None
	elif isinstance(obj, (str, float, int)):
	return obj

	{pkgs}:
	{
	# Fetches a tag from a github repo.
	fetchRepo = {owner, repo, tag, sha256, requireToken ? false}:
	let
	url = "https://api.github.com/repos/${owner}/${repo}/tarball/${tag}";
	in
	pkgs.stdenv.mkDerivation {
	inherit requireToken;
	name = "${repo}-${tag}-snapshot.tar.gz";

	git clone https://github.com/adnelson/nixfromnpm
	cd nixfromnpm
	git checkout -b fetch_dev_dependencies
	git pull origin fetch_dev_dependencies
	nix-shell --pure

	# In nix-shell:
	cabal configure
	cabal build
	cabal run -- -p grunt -o results