Synnefo

# vim: ts=4 sts=4 et ai sw=4 fileencoding=utf-8

#

# Copyright © 2010 Greek Research and Technology Network

#

import re

from django.conf.urls.defaults import url

_accept_re = re.compile(r'([^\s;,]+)(?:[^,]*?;\s*q=(\d*(?:\.\d+)?))?')

def parse_accept_header(value):

    """Parse an HTTP Accept header

    Returns an ordered by quality list of tuples (value, quality)

    """

    if not value:

        return []

    result = []

    for match in _accept_re.finditer(value):

        quality = match.group(2)

        if not quality:

            quality = 1

        else:

            quality = max(min(float(quality), 1), 0)

        result.append((match.group(1), quality))

    # sort by quality

    result.sort(key=lambda x: x[1])

    return result

def url_with_format(regex, *args, **kwargs):

    """

    An extended url() that adds an .json/.xml suffix to the end to avoid DRY

    """

    if regex[-1] == '$' and regex[-2] != '\\':

        regex = regex[:-1]

    regex = regex + r'(\.(?P<emitter_format>json|xml))?$'

    return url(regex, *args, **kwargs)