allow options/arguments to be passed through to the underlying

        celery command.

        """

        raise NotImplementedError("Abstract Method.")

    def bootstrap_config(self, conf):

        """

        Loads the pylons configuration.

        """

        from pylons import config as pylonsconfig

        self.path_to_ini_file = os.path.realpath(conf)

        conf = paste.deploy.appconfig('config:' + self.path_to_ini_file)

        pylonsconfig.init_app(conf.global_conf, conf.local_conf)

    def _init_session(self):

        """

        Inits SqlAlchemy Session

        """

        logging.config.fileConfig(self.path_to_ini_file)

        from pylons import config

        from kallithea.model import init_model

        from kallithea.lib.utils2 import engine_from_config

        add_cache(config)

        engine = engine_from_config(config, 'sqlalchemy.db1.')

        init_model(engine)

def check_git_version():

    """

    Checks what version of git is installed in system, and issues a warning

    if it's too old for Kallithea to work properly.

    """

    from kallithea import BACKENDS

    from kallithea.lib.vcs.backends.git.repository import GitRepository

    from kallithea.lib.vcs.conf import settings

    from distutils.version import StrictVersion

    if 'git' not in BACKENDS:

        return None

    stdout, stderr = GitRepository._run_git_command(['--version'], _bare=True,

                                                    _safe=True)

    m = re.search("\d+.\d+.\d+", stdout)

    if m:

        ver = StrictVersion(m.group(0))

    else:

        ver = StrictVersion('0.0.0')

    req_ver = StrictVersion('1.7.4')

    log.debug('Git executable: "%s" version %s detected: %s',

              settings.GIT_EXECUTABLE_PATH, ver, stdout)

    if stderr:

        log.warning('Error detecting git version: %r', stderr)

    elif ver < req_ver:

        log.warning('Kallithea detected git version %s, which is too old '

                    'for the system to function properly. '

                    'Please upgrade to version %s or later.' % (ver, req_ver))

    return ver

@decorator.decorator

def jsonify(func, *args, **kwargs):

    """Action decorator that formats output for JSON

    Given a function that will return content, this decorator will turn

    the result into JSON, with a content-type of 'application/json' and

    output it.

    """

    from pylons.decorators.util import get_pylons

    from kallithea.lib.compat import json

    pylons = get_pylons(args)

    pylons.response.headers['Content-Type'] = 'application/json; charset=utf-8'

    data = func(*args, **kwargs)

    if isinstance(data, (list, tuple)):

        msg = "JSON responses with Array envelopes are susceptible to " \

              "cross-site data leak attacks, see " \

              "http://wiki.pylonshq.com/display/pylonsfaq/Warnings"

        warnings.warn(msg, Warning, 2)

        log.warning(msg)

    log.debug("Returning JSON wrapped action output")

    return json.dumps(data, encoding='utf-8')

def conditional_cache(region, prefix, condition, func):

    """

    Conditional caching function use like::

        def _c(arg):

            #heavy computation function

            return data

        compute = conditional_cache('short_term', 'cache_desc', condition=True, func=func)

        return compute(arg)

    :param region: name of cache region

    :param prefix: cache region prefix

    :param condition: condition for cache to be triggered, and return data cached

    :param func: wrapped heavy function to compute

    """

    wrapped = func

    if condition:

        log.debug('conditional_cache: True, wrapping call of '

                  'func: %s into %s region cache' % (region, func))

        wrapped = _cache_decorate((prefix,), None, None, region)(func)

    return wrapped