flask/flask/wrappers.py

# -*- coding: utf-8 -*-
"""
    flask.wrappers
    ~~~~~~~~~~~~~~

    Implements the WSGI wrappers (request and response).

    :copyright: (c) 2010 by Armin Ronacher.
    :license: BSD, see LICENSE for more details.
"""

from werkzeug import Request as RequestBase, Response as ResponseBase, \
    cached_property

from .helpers import json, _assert_have_json
from .globals import _request_ctx_stack


class Request(RequestBase):
    """The request object used by default in flask.  Remembers the
    matched endpoint and view arguments.

    It is what ends up as :class:`~flask.request`.  If you want to replace
    the request object used you can subclass this and set
    :attr:`~flask.Flask.request_class` to your subclass.
    """

    #: the internal URL rule that matched the request.  This can be
    #: useful to inspect which methods are allowed for the URL from
    #: a before/after handler (``request.url_rule.methods``) etc.
    #:
    #: .. versionadded:: 0.6
    url_rule = None

    #: a dict of view arguments that matched the request.  If an exception
    #: happened when matching, this will be `None`.
    view_args = None

    #: if matching the URL failed, this is the exception that will be
    #: raised / was raised as part of the request handling.  This is
    #: usually a :exc:`~werkzeug.exceptions.NotFound` exception or
    #: something similar.
    routing_exception = None

    @property
    def max_content_length(self):
        """Read-only view of the `MAX_CONTENT_LENGTH` config key."""
        ctx = _request_ctx_stack.top
        if ctx is not None:
            return ctx.app.config['MAX_CONTENT_LENGTH']

    @property
    def endpoint(self):
        """The endpoint that matched the request.  This in combination with
        :attr:`view_args` can be used to reconstruct the same or a
        modified URL.  If an exception happened when matching, this will
        be `None`.
        """
        if self.url_rule is not None:
            return self.url_rule.endpoint

    @property
    def module(self):
        """The name of the current module"""
        if self.url_rule and '.' in self.url_rule.endpoint:
            return self.url_rule.endpoint.rsplit('.', 1)[0]

    @cached_property
    def json(self):
        """If the mimetype is `application/json` this will contain the
        parsed JSON data.
        """
        if __debug__:
            _assert_have_json()
        if self.mimetype == 'application/json':
            return json.loads(self.data)


class Response(ResponseBase):
    """The response object that is used by default in flask.  Works like the
    response object from Werkzeug but is set to have a HTML mimetype by
    default.  Quite often you don't have to create this object yourself because
    :meth:`~flask.Flask.make_response` will take care of that for you.

    If you want to replace the response object used you can subclass this and
    set :attr:`~flask.Flask.response_class` to your subclass.
    """
    default_mimetype = 'text/html'