urlpatterns.py 文件源码

def format_suffix_patterns(urlpatterns, suffix_required=False, allowed=None):
    """
    Supplement existing urlpatterns with corresponding patterns that also
    include a '.format' suffix.  Retains urlpattern ordering.

    urlpatterns:
        A list of URL patterns.

    suffix_required:
        If `True`, only suffixed URLs will be generated, and non-suffixed
        URLs will not be used.  Defaults to `False`.

    allowed:
        An optional tuple/list of allowed suffixes.  eg ['json', 'api']
        Defaults to `None`, which allows any suffix.
    """
    suffix_kwarg = api_settings.FORMAT_SUFFIX_KWARG
    if allowed:
        if len(allowed) == 1:
            allowed_pattern = allowed[0]
        else:
            allowed_pattern = '(%s)' % '|'.join(allowed)
        suffix_pattern = r'\.(?P<%s>%s)/?$' % (suffix_kwarg, allowed_pattern)
    else:
        suffix_pattern = r'\.(?P<%s>[a-z0-9]+)/?$' % suffix_kwarg

    return apply_suffix_patterns(urlpatterns, suffix_pattern, suffix_required)