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