codekingpro/portable-devtools

1import base642import re3 4import pyparsing as pp5 6from .error import *7 8 9try:  # pyparsing>=3.0.010    downcaseTokens = pp.common.downcaseTokens11except AttributeError:12    downcaseTokens = pp.downcaseTokens13 14UNQUOTE_PAIRS = re.compile(r"\\(.)")15unquote = lambda s, l, t: UNQUOTE_PAIRS.sub(r"\1", t[0][1:-1])16 17# https://tools.ietf.org/html/rfc7235#section-1.218# https://tools.ietf.org/html/rfc7235#appendix-B19tchar = "!#$%&'*+-.^_`|~" + pp.nums + pp.alphas20token = pp.Word(tchar).setName("token")21token68 = pp.Combine(pp.Word("-._~+/" + pp.nums + pp.alphas) + pp.Optional(pp.Word("=").leaveWhitespace())).setName(22    "token68"23)24 25quoted_string = pp.dblQuotedString.copy().setName("quoted-string").setParseAction(unquote)26auth_param_name = token.copy().setName("auth-param-name").addParseAction(downcaseTokens)27auth_param = auth_param_name + pp.Suppress("=") + (quoted_string | token)28params = pp.Dict(pp.delimitedList(pp.Group(auth_param)))29 30scheme = token("scheme")31challenge = scheme + (params("params") | token68("token"))32 33authentication_info = params.copy()34www_authenticate = pp.delimitedList(pp.Group(challenge))35 36 37def _parse_authentication_info(headers, headername="authentication-info"):38    """https://tools.ietf.org/html/rfc761539    """40    header = headers.get(headername, "").strip()41    if not header:42        return {}43    try:44        parsed = authentication_info.parseString(header)45    except pp.ParseException as ex:46        # print(ex.explain(ex))47        raise MalformedHeader(headername)48 49    return parsed.asDict()50 51 52def _parse_www_authenticate(headers, headername="www-authenticate"):53    """Returns a dictionary of dictionaries, one dict per auth_scheme."""54    header = headers.get(headername, "").strip()55    if not header:56        return {}57    try:58        parsed = www_authenticate.parseString(header)59    except pp.ParseException as ex:60        # print(ex.explain(ex))61        raise MalformedHeader(headername)62 63    retval = {64        challenge["scheme"].lower(): challenge["params"].asDict()65        if "params" in challenge66        else {"token": challenge.get("token")}67        for challenge in parsed68    }69    return retval70