Extra Wrappers

Extra Wrappers

Extra wrappers or mixins contributed by the community. These wrappers canbe 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 theJSONRequestMixin.

class werkzeug.contrib.wrappers.JSONRequestMixin
Add json method to a request object. This will parse the input datathrough simplejson if possible.

BadRequest will be raised if the content-typeis not json or if the data itself cannot be parsed as json.

json
Get the result of simplejson.loads if possible.

class werkzeug.contrib.wrappers.ProtobufRequestMixin
Add protobuf parsing method to a request object. This will parse theinput data through protobuf [http://code.google.com/p/protobuf/] if possible.

BadRequest will be raised if the content-typeis not protobuf or if the data itself cannot be parsed property.

parse_protobuf(proto_type)
Parse the data into an instance of proto_type.

protobuf_check_initialization = True
by default the ProtobufRequestMixin will raise aBadRequest if the object is notinitialized. You can bypass that check by setting thisattribute to False.

class werkzeug.contrib.wrappers.RoutingArgsRequestMixin
This request mixin adds support for the wsgiorg routing argsspecification [http://www.wsgi.org/wsgi/Specifications/routing_args].

routing_args
The positional URL arguments as tuple.

routing_vars
The keyword URL arguments as dict.

class werkzeug.contrib.wrappers.ReverseSlashBehaviorRequestMixin
This mixin reverses the trailing slash behavior of script_rootand path. This makes it possible to use urljoin()directly on the paths.

Because it changes the behavior or Request this class has to bemixed 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

path
Requested path as unicode. This works a bit like the regular pathinfo in the WSGI environment but will not include a leading slash.

script_root
The root path of the script includling a trailing slash.

class werkzeug.contrib.wrappers.DynamicCharsetRequestMixin
“If this mixin is mixed into a request class it will providea dynamic charset attribute. This means that if the charset istransmitted in the content type headers it's used from there.

Because it changes the behavior or Request this class hasto be mixed in before the actual request class:

class MyRequest(DynamicCharsetRequestMixin, Request):
    pass

By default the request object assumes that the URL charset is thesame as the data charset. If the charset varies on each requestbased on the transmitted data it's not a good idea to let the URLschange based on that. Most browsers assume either utf-8 or latin1for the URLs if they have troubles figuring out. It's stronglyrecommended to set the URL charset to utf-8:

class MyRequest(DynamicCharsetRequestMixin, Request):
    url_charset = 'utf-8'

0.6 新版功能.

charset
The charset from the content type.

default_charset = 'latin1'
the default charset that is assumed if the content type headeris missing or does not contain a charset parameter. The defaultis latin1 which is what HTTP specifies as default charset.You may however want to set this to utf-8 to better supportbrowsers that do not transmit a charset for incoming data.

unknown_charset(charset)
Called if a charset was provided but is not supported bythe Python codecs module. By default latin1 is assumed thento not lose any information, you may override this method tochange the behavior.

参数:	charset – the charset that was not found.
返回:	the replacement charset.

class werkzeug.contrib.wrappers.DynamicCharsetResponseMixin
If this mixin is mixed into a response class it will providea dynamic charset attribute. This means that if the charset islooked up and stored in the Content-Type header and updatesitself automatically. This also means a small performance hit butcan be useful if you're working with different charsets onresponses.

Because the charset attribute is no a property at class-level, thedefault value is stored in default_charset.

Because it changes the behavior or Response this class hasto be mixed in before the actual response class:

class MyResponse(DynamicCharsetResponseMixin, Response):
    pass

0.6 新版功能.

charset
The charset for the response. It's stored inside theContent-Type header as a parameter.

default_charset = 'utf-8'
the default charset.