Source code for molten.http.query_params
# This file is a part of molten.
#
# Copyright (C) 2018 CLEARTYPE SRL <[email protected]>
#
# molten is free software; you can redistribute it and/or modify it
# under the terms of the GNU Lesser General Public License as published by
# the Free Software Foundation, either version 3 of the License, or (at
# your option) any later version.
#
# molten is distributed in the hope that it will be useful, but WITHOUT
# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
# FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
# License for more details.
#
# You should have received a copy of the GNU Lesser General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
from typing import Dict, List, Optional, Union
from urllib.parse import parse_qsl
from ..common import MultiDict
from ..errors import ParamMissing
from ..typing import Environ
ParamsDict = Dict[str, Union[str, List[str]]]
[docs]class QueryParams(MultiDict[str, str]):
"""A mapping from param names to lists of values. Once
constructed, these instances cannot be modified.
"""
[docs] @classmethod
def from_environ(cls, environ: Environ) -> "QueryParams":
"""Construct a QueryParams instance from a WSGI environ.
"""
return cls.parse(environ.get("QUERY_STRING", ""))
[docs] @classmethod
def parse(cls, query_string: str) -> "QueryParams":
"""Construct a QueryParams instance from a query string.
"""
return cls(parse_qsl(query_string))
[docs] def get(self, name: str, default: Optional[str] = None) -> Optional[str]:
"""Get the last value for a given key.
"""
try:
return self[name]
except ParamMissing:
return default
def __getitem__(self, name: str) -> str:
"""Get the last value for a given key.
Raises:
ParamMissing: When the key is missing.
"""
try:
return self._data[name][-1]
except IndexError:
raise ParamMissing(name)