279 lines
10 KiB
Python
279 lines
10 KiB
Python
|
# -*- coding: utf-8 -*-
|
||
|
"""
|
||
|
werkzeug.contrib.wrappers
|
||
|
~~~~~~~~~~~~~~~~~~~~~~~~~
|
||
|
|
||
|
Extra wrappers or mixins contributed by the community. These wrappers can
|
||
|
be mixed in into request objects to add extra functionality.
|
||
|
|
||
|
Example::
|
||
|
|
||
|
from werkzeug.wrappers import Request as RequestBase
|
||
|
from werkzeug.contrib.wrappers import JSONRequestMixin
|
||
|
|
||
|
class Request(RequestBase, JSONRequestMixin):
|
||
|
pass
|
||
|
|
||
|
Afterwards this request object provides the extra functionality of the
|
||
|
:class:`JSONRequestMixin`.
|
||
|
|
||
|
:copyright: (c) 2013 by the Werkzeug Team, see AUTHORS for more details.
|
||
|
:license: BSD, see LICENSE for more details.
|
||
|
"""
|
||
|
import codecs
|
||
|
try:
|
||
|
from simplejson import loads
|
||
|
except ImportError:
|
||
|
from json import loads
|
||
|
|
||
|
from werkzeug.exceptions import BadRequest
|
||
|
from werkzeug.utils import cached_property
|
||
|
from werkzeug.http import dump_options_header, parse_options_header
|
||
|
from werkzeug._compat import wsgi_decoding_dance
|
||
|
|
||
|
|
||
|
def is_known_charset(charset):
|
||
|
"""Checks if the given charset is known to Python."""
|
||
|
try:
|
||
|
codecs.lookup(charset)
|
||
|
except LookupError:
|
||
|
return False
|
||
|
return True
|
||
|
|
||
|
|
||
|
class JSONRequestMixin(object):
|
||
|
"""Add json method to a request object. This will parse the input data
|
||
|
through simplejson if possible.
|
||
|
|
||
|
:exc:`~werkzeug.exceptions.BadRequest` will be raised if the content-type
|
||
|
is not json or if the data itself cannot be parsed as json.
|
||
|
"""
|
||
|
|
||
|
@cached_property
|
||
|
def json(self):
|
||
|
"""Get the result of simplejson.loads if possible."""
|
||
|
if 'json' not in self.environ.get('CONTENT_TYPE', ''):
|
||
|
raise BadRequest('Not a JSON request')
|
||
|
try:
|
||
|
return loads(self.data)
|
||
|
except Exception:
|
||
|
raise BadRequest('Unable to read JSON request')
|
||
|
|
||
|
|
||
|
class ProtobufRequestMixin(object):
|
||
|
"""Add protobuf parsing method to a request object. This will parse the
|
||
|
input data through `protobuf`_ if possible.
|
||
|
|
||
|
:exc:`~werkzeug.exceptions.BadRequest` will be raised if the content-type
|
||
|
is not protobuf or if the data itself cannot be parsed property.
|
||
|
|
||
|
.. _protobuf: http://code.google.com/p/protobuf/
|
||
|
"""
|
||
|
|
||
|
#: by default the :class:`ProtobufRequestMixin` will raise a
|
||
|
#: :exc:`~werkzeug.exceptions.BadRequest` if the object is not
|
||
|
#: initialized. You can bypass that check by setting this
|
||
|
#: attribute to `False`.
|
||
|
protobuf_check_initialization = True
|
||
|
|
||
|
def parse_protobuf(self, proto_type):
|
||
|
"""Parse the data into an instance of proto_type."""
|
||
|
if 'protobuf' not in self.environ.get('CONTENT_TYPE', ''):
|
||
|
raise BadRequest('Not a Protobuf request')
|
||
|
|
||
|
obj = proto_type()
|
||
|
try:
|
||
|
obj.ParseFromString(self.data)
|
||
|
except Exception:
|
||
|
raise BadRequest("Unable to parse Protobuf request")
|
||
|
|
||
|
# Fail if not all required fields are set
|
||
|
if self.protobuf_check_initialization and not obj.IsInitialized():
|
||
|
raise BadRequest("Partial Protobuf request")
|
||
|
|
||
|
return obj
|
||
|
|
||
|
|
||
|
class RoutingArgsRequestMixin(object):
|
||
|
"""This request mixin adds support for the wsgiorg routing args
|
||
|
`specification`_.
|
||
|
|
||
|
.. _specification: http://www.wsgi.org/wsgi/Specifications/routing_args
|
||
|
"""
|
||
|
|
||
|
def _get_routing_args(self):
|
||
|
return self.environ.get('wsgiorg.routing_args', (()))[0]
|
||
|
|
||
|
def _set_routing_args(self, value):
|
||
|
if self.shallow:
|
||
|
raise RuntimeError('A shallow request tried to modify the WSGI '
|
||
|
'environment. If you really want to do that, '
|
||
|
'set `shallow` to False.')
|
||
|
self.environ['wsgiorg.routing_args'] = (value, self.routing_vars)
|
||
|
|
||
|
routing_args = property(_get_routing_args, _set_routing_args, doc='''
|
||
|
The positional URL arguments as `tuple`.''')
|
||
|
del _get_routing_args, _set_routing_args
|
||
|
|
||
|
def _get_routing_vars(self):
|
||
|
rv = self.environ.get('wsgiorg.routing_args')
|
||
|
if rv is not None:
|
||
|
return rv[1]
|
||
|
rv = {}
|
||
|
if not self.shallow:
|
||
|
self.routing_vars = rv
|
||
|
return rv
|
||
|
|
||
|
def _set_routing_vars(self, value):
|
||
|
if self.shallow:
|
||
|
raise RuntimeError('A shallow request tried to modify the WSGI '
|
||
|
'environment. If you really want to do that, '
|
||
|
'set `shallow` to False.')
|
||
|
self.environ['wsgiorg.routing_args'] = (self.routing_args, value)
|
||
|
|
||
|
routing_vars = property(_get_routing_vars, _set_routing_vars, doc='''
|
||
|
The keyword URL arguments as `dict`.''')
|
||
|
del _get_routing_vars, _set_routing_vars
|
||
|
|
||
|
|
||
|
class ReverseSlashBehaviorRequestMixin(object):
|
||
|
"""This mixin reverses the trailing slash behavior of :attr:`script_root`
|
||
|
and :attr:`path`. This makes it possible to use :func:`~urlparse.urljoin`
|
||
|
directly on the paths.
|
||
|
|
||
|
Because it changes the behavior or :class:`Request` this class has to be
|
||
|
mixed in *before* the actual request class::
|
||
|
|
||
|
class MyRequest(ReverseSlashBehaviorRequestMixin, Request):
|
||
|
pass
|
||
|
|
||
|
This example shows the differences (for an application mounted on
|
||
|
`/application` and the request going to `/application/foo/bar`):
|
||
|
|
||
|
+---------------+-------------------+---------------------+
|
||
|
| | normal behavior | reverse behavior |
|
||
|
+===============+===================+=====================+
|
||
|
| `script_root` | ``/application`` | ``/application/`` |
|
||
|
+---------------+-------------------+---------------------+
|
||
|
| `path` | ``/foo/bar`` | ``foo/bar`` |
|
||
|
+---------------+-------------------+---------------------+
|
||
|
"""
|
||
|
|
||
|
@cached_property
|
||
|
def path(self):
|
||
|
"""Requested path as unicode. This works a bit like the regular path
|
||
|
info in the WSGI environment but will not include a leading slash.
|
||
|
"""
|
||
|
path = wsgi_decoding_dance(self.environ.get('PATH_INFO') or '',
|
||
|
self.charset, self.encoding_errors)
|
||
|
return path.lstrip('/')
|
||
|
|
||
|
@cached_property
|
||
|
def script_root(self):
|
||
|
"""The root path of the script includling a trailing slash."""
|
||
|
path = wsgi_decoding_dance(self.environ.get('SCRIPT_NAME') or '',
|
||
|
self.charset, self.encoding_errors)
|
||
|
return path.rstrip('/') + '/'
|
||
|
|
||
|
|
||
|
class DynamicCharsetRequestMixin(object):
|
||
|
""""If this mixin is mixed into a request class it will provide
|
||
|
a dynamic `charset` attribute. This means that if the charset is
|
||
|
transmitted in the content type headers it's used from there.
|
||
|
|
||
|
Because it changes the behavior or :class:`Request` this class has
|
||
|
to be mixed in *before* the actual request class::
|
||
|
|
||
|
class MyRequest(DynamicCharsetRequestMixin, Request):
|
||
|
pass
|
||
|
|
||
|
By default the request object assumes that the URL charset is the
|
||
|
same as the data charset. If the charset varies on each request
|
||
|
based on the transmitted data it's not a good idea to let the URLs
|
||
|
change based on that. Most browsers assume either utf-8 or latin1
|
||
|
for the URLs if they have troubles figuring out. It's strongly
|
||
|
recommended to set the URL charset to utf-8::
|
||
|
|
||
|
class MyRequest(DynamicCharsetRequestMixin, Request):
|
||
|
url_charset = 'utf-8'
|
||
|
|
||
|
.. versionadded:: 0.6
|
||
|
"""
|
||
|
|
||
|
#: the default charset that is assumed if the content type header
|
||
|
#: is missing or does not contain a charset parameter. The default
|
||
|
#: is latin1 which is what HTTP specifies as default charset.
|
||
|
#: You may however want to set this to utf-8 to better support
|
||
|
#: browsers that do not transmit a charset for incoming data.
|
||
|
default_charset = 'latin1'
|
||
|
|
||
|
def unknown_charset(self, charset):
|
||
|
"""Called if a charset was provided but is not supported by
|
||
|
the Python codecs module. By default latin1 is assumed then
|
||
|
to not lose any information, you may override this method to
|
||
|
change the behavior.
|
||
|
|
||
|
:param charset: the charset that was not found.
|
||
|
:return: the replacement charset.
|
||
|
"""
|
||
|
return 'latin1'
|
||
|
|
||
|
@cached_property
|
||
|
def charset(self):
|
||
|
"""The charset from the content type."""
|
||
|
header = self.environ.get('CONTENT_TYPE')
|
||
|
if header:
|
||
|
ct, options = parse_options_header(header)
|
||
|
charset = options.get('charset')
|
||
|
if charset:
|
||
|
if is_known_charset(charset):
|
||
|
return charset
|
||
|
return self.unknown_charset(charset)
|
||
|
return self.default_charset
|
||
|
|
||
|
|
||
|
class DynamicCharsetResponseMixin(object):
|
||
|
"""If this mixin is mixed into a response class it will provide
|
||
|
a dynamic `charset` attribute. This means that if the charset is
|
||
|
looked up and stored in the `Content-Type` header and updates
|
||
|
itself automatically. This also means a small performance hit but
|
||
|
can be useful if you're working with different charsets on
|
||
|
responses.
|
||
|
|
||
|
Because the charset attribute is no a property at class-level, the
|
||
|
default value is stored in `default_charset`.
|
||
|
|
||
|
Because it changes the behavior or :class:`Response` this class has
|
||
|
to be mixed in *before* the actual response class::
|
||
|
|
||
|
class MyResponse(DynamicCharsetResponseMixin, Response):
|
||
|
pass
|
||
|
|
||
|
.. versionadded:: 0.6
|
||
|
"""
|
||
|
|
||
|
#: the default charset.
|
||
|
default_charset = 'utf-8'
|
||
|
|
||
|
def _get_charset(self):
|
||
|
header = self.headers.get('content-type')
|
||
|
if header:
|
||
|
charset = parse_options_header(header)[1].get('charset')
|
||
|
if charset:
|
||
|
return charset
|
||
|
return self.default_charset
|
||
|
|
||
|
def _set_charset(self, charset):
|
||
|
header = self.headers.get('content-type')
|
||
|
ct, options = parse_options_header(header)
|
||
|
if not ct:
|
||
|
raise TypeError('Cannot set charset if Content-Type '
|
||
|
'header is missing.')
|
||
|
options['charset'] = charset
|
||
|
self.headers['Content-Type'] = dump_options_header(ct, options)
|
||
|
|
||
|
charset = property(_get_charset, _set_charset, doc="""
|
||
|
The charset for the response. It's stored inside the
|
||
|
Content-Type header as a parameter.""")
|
||
|
del _get_charset, _set_charset
|