nix-aurora-binding-helper.py

import subprocess

from apache.aurora.client.binding_helper import (BindingHelper,
                                                 CachingBindingHelper)
from apache.aurora.client.config import GlobalHookRegistry
from pystachio.matcher import Any, Matcher
from twitter.common import log


class NixHelper(CachingBindingHelper):
  @property
  def name(self):
    return 'Nix'

  @property
  def matcher(self):
    return Matcher('Nix.*')[Any]

  def uncached_bind(self, config, match, env, binding_dict):
    package = match[1]
    ref = Ref.from_address('%s[%s]' % match)

    nix_attrib = nix_packages[package]
    store_path = self._nix_realise(nix_attrib)

    binding = {ref: store_path}
    config.bind(binding)
    return binding

  def _nix_realise(self, attribute):
    log.info('Assembling: %s', attribute)
    store_path = subprocess.check_output(
        ['nix-build', '-A', attribute, '--no-out-link']).strip()

    log.debug('Store path: %s', store_path)
    return store_path


BindingHelper.register(NixHelper())