from functools import update_wrapper
from io import BytesIO
from .._compat import to_native
from .._compat import to_unicode
from .._compat import wsgi_decoding_dance
from .._compat import wsgi_get_bytes
from ..datastructures import CombinedMultiDict
from ..datastructures import EnvironHeaders
from ..datastructures import ImmutableList
from ..datastructures import ImmutableMultiDict
from ..datastructures import iter_multi_items
from ..datastructures import MultiDict
from ..formparser import default_stream_factory
from ..formparser import FormDataParser
from ..http import parse_cookie
from ..http import parse_list_header
from ..http import parse_options_header
from ..urls import url_decode
from ..utils import cached_property
from ..utils import environ_property
from ..wsgi import get_content_length
from ..wsgi import get_current_url
from ..wsgi import get_host
from ..wsgi import get_input_stream
class BaseRequest(object):
"""Very basic request object. This does not implement advanced stuff like
entity tag parsing or cache controls. The request object is created with
the WSGI environment as first argument and will add itself to the WSGI
environment as ``'werkzeug.request'`` unless it's created with
`populate_request` set to False.
There are a couple of mixins available that add additional functionality
to the request object, there is also a class called `Request` which
subclasses `BaseRequest` and all the important mixins.
It's a good idea to create a custom subclass of the :class:`BaseRequest`
and add missing functionality either via mixins or direct implementation.
Here an example for such subclasses::
from werkzeug.wrappers import BaseRequest, ETagRequestMixin
class Request(BaseRequest, ETagRequestMixin):
pass
Request objects are **read only**. As of 0.5 modifications are not
allowed in any place. Unlike the lower level parsing functions the
request object will use immutable objects everywhere possible.
Per default the request object will assume all the text data is `utf-8`
encoded. Please refer to :doc:`the unicode chapter ` for more
details about customizing the behavior.
Per default the request object will be added to the WSGI
environment as `werkzeug.request` to support the debugging system.
If you don't want that, set `populate_request` to `False`.
If `shallow` is `True` the environment is initialized as shallow
object around the environ. Every operation that would modify the
environ in any way (such as consuming form data) raises an exception
unless the `shallow` attribute is explicitly set to `False`. This
is useful for middlewares where you don't want to consume the form
data by accident. A shallow request is not populated to the WSGI
environment.
.. versionchanged:: 0.5
read-only mode was enforced by using immutables classes for all
data.
"""
#: the charset for the request, defaults to utf-8
charset = "utf-8"
#: the error handling procedure for errors, defaults to 'replace'
encoding_errors = "replace"
#: the maximum content length. This is forwarded to the form data
#: parsing function (:func:`parse_form_data`). When set and the
#: :attr:`form` or :attr:`files` attribute is accessed and the
#: parsing fails because more than the specified value is transmitted
#: a :exc:`~werkzeug.exceptions.RequestEntityTooLarge` exception is raised.
#:
#: Have a look at :ref:`dealing-with-request-data` for more details.
#:
#: .. versionadded:: 0.5
max_content_length = None
#: the maximum form field size. This is forwarded to the form data
#: parsing function (:func:`parse_form_data`). When set and the
#: :attr:`form` or :attr:`files` attribute is accessed and the
#: data in memory for post data is longer than the specified value a
#: :exc:`~werkzeug.exceptions.RequestEntityTooLarge` exception is raised.
#:
#: Have a look at :ref:`dealing-with-request-data` for more details.
#:
#: .. versionadded:: 0.5
max_form_memory_size = None
#: the class to use for `args` and `form`. The default is an
#: :class:`~werkzeug.datastructures.ImmutableMultiDict` which supports
#: multiple values per key. alternatively it makes sense to use an
#: :class:`~werkzeug.datastructures.ImmutableOrderedMultiDict` which
#: preserves order or a :class:`~werkzeug.datastructures.ImmutableDict`
#: which is the fastest but only remembers the last key. It is also
#: possible to use mutable structures, but this is not recommended.
#:
#: .. versionadded:: 0.6
parameter_storage_class = ImmutableMultiDict
#: the type to be used for list values from the incoming WSGI environment.
#: By default an :class:`~werkzeug.datastructures.ImmutableList` is used
#: (for example for :attr:`access_list`).
#:
#: .. versionadded:: 0.6
list_storage_class = ImmutableList
#: The type to be used for dict values from the incoming WSGI
#: environment. (For example for :attr:`cookies`.) By default an
#: :class:`~werkzeug.datastructures.ImmutableMultiDict` is used.
#:
#: .. versionchanged:: 1.0.0
#: Changed to ``ImmutableMultiDict`` to support multiple values.
#:
#: .. versionadded:: 0.6
dict_storage_class = ImmutableMultiDict
#: The form data parser that shoud be used. Can be replaced to customize
#: the form date parsing.
form_data_parser_class = FormDataParser
#: Optionally a list of hosts that is trusted by this request. By default
#: all hosts are trusted which means that whatever the client sends the
#: host is will be accepted.
#:
#: Because `Host` and `X-Forwarded-Host` headers can be set to any value by
#: a malicious client, it is recommended to either set this property or
#: implement similar validation in the proxy (if application is being run
#: behind one).
#:
#: .. versionadded:: 0.9
trusted_hosts = None
#: Indicates whether the data descriptor should be allowed to read and
#: buffer up the input stream. By default it's enabled.
#:
#: .. versionadded:: 0.9
disable_data_descriptor = False
def __init__(self, environ, populate_request=True, shallow=False):
self.environ = environ
if populate_request and not shallow:
self.environ["werkzeug.request"] = self
self.shallow = shallow
def __repr__(self):
# make sure the __repr__ even works if the request was created
# from an invalid WSGI environment. If we display the request
# in a debug session we don't want the repr to blow up.
args = []
try:
args.append("'%s'" % to_native(self.url, self.url_charset))
args.append("[%s]" % self.method)
except Exception:
args.append("(invalid WSGI environ)")
return "<%s %s>" % (self.__class__.__name__, " ".join(args))
@property
def url_charset(self):
"""The charset that is assumed for URLs. Defaults to the value
of :attr:`charset`.
.. versionadded:: 0.6
"""
return self.charset
@classmethod
def from_values(cls, *args, **kwargs):
"""Create a new request object based on the values provided. If
environ is given missing values are filled from there. This method is
useful for small scripts when you need to simulate a request from an URL.
Do not use this method for unittesting, there is a full featured client
object (:class:`Client`) that allows to create multipart requests,
support for cookies etc.
This accepts the same options as the
:class:`~werkzeug.test.EnvironBuilder`.
.. versionchanged:: 0.5
This method now accepts the same arguments as
:class:`~werkzeug.test.EnvironBuilder`. Because of this the
`environ` parameter is now called `environ_overrides`.
:return: request object
"""
from ..test import EnvironBuilder
charset = kwargs.pop("charset", cls.charset)
kwargs["charset"] = charset
builder = EnvironBuilder(*args, **kwargs)
try:
return builder.get_request(cls)
finally:
builder.close()
@classmethod
def application(cls, f):
"""Decorate a function as responder that accepts the request as
the last argument. This works like the :func:`responder`
decorator but the function is passed the request object as the
last argument and the request object will be closed
automatically::
@Request.application
def my_wsgi_app(request):
return Response('Hello World!')
As of Werkzeug 0.14 HTTP exceptions are automatically caught and
converted to responses instead of failing.
:param f: the WSGI callable to decorate
:return: a new WSGI callable
"""
#: return a callable that wraps the -2nd argument with the request
#: and calls the function with all the arguments up to that one and
#: the request. The return value is then called with the latest
#: two arguments. This makes it possible to use this decorator for
#: both standalone WSGI functions as well as bound methods and
#: partially applied functions.
from ..exceptions import HTTPException
def application(*args):
request = cls(args[-2])
with request:
try:
resp = f(*args[:-2] + (request,))
except HTTPException as e:
resp = e.get_response(args[-2])
return resp(*args[-2:])
return update_wrapper(application, f)
def _get_file_stream(
self, total_content_length, content_type, filename=None, content_length=None
):
"""Called to get a stream for the file upload.
This must provide a file-like class with `read()`, `readline()`
and `seek()` methods that is both writeable and readable.
The default implementation returns a temporary file if the total
content length is higher than 500KB. Because many browsers do not
provide a content length for the files only the total content
length matters.
:param total_content_length: the total content length of all the
data in the request combined. This value
is guaranteed to be there.
:param content_type: the mimetype of the uploaded file.
:param filename: the filename of the uploaded file. May be `None`.
:param content_length: the length of this file. This value is usually
not provided because webbrowsers do not provide
this value.
"""
return default_stream_factory(
total_content_length=total_content_length,
filename=filename,
content_type=content_type,
content_length=content_length,
)
@property
def want_form_data_parsed(self):
"""Returns True if the request method carries content. As of
Werkzeug 0.9 this will be the case if a content type is transmitted.
.. versionadded:: 0.8
"""
return bool(self.environ.get("CONTENT_TYPE"))
def make_form_data_parser(self):
"""Creates the form data parser. Instantiates the
:attr:`form_data_parser_class` with some parameters.
.. versionadded:: 0.8
"""
return self.form_data_parser_class(
self._get_file_stream,
self.charset,
self.encoding_errors,
self.max_form_memory_size,
self.max_content_length,
self.parameter_storage_class,
)
def _load_form_data(self):
"""Method used internally to retrieve submitted data. After calling
this sets `form` and `files` on the request object to multi dicts
filled with the incoming form data. As a matter of fact the input
stream will be empty afterwards. You can also call this method to
force the parsing of the form data.
.. versionadded:: 0.8
"""
# abort early if we have already consumed the stream
if "form" in self.__dict__:
return
_assert_not_shallow(self)
if self.want_form_data_parsed:
content_type = self.environ.get("CONTENT_TYPE", "")
content_length = get_content_length(self.environ)
mimetype, options = parse_options_header(content_type)
parser = self.make_form_data_parser()
data = parser.parse(
self._get_stream_for_parsing(), mimetype, content_length, options
)
else:
data = (
self.stream,
self.parameter_storage_class(),
self.parameter_storage_class(),
)
# inject the values into the instance dict so that we bypass
# our cached_property non-data descriptor.
d = self.__dict__
d["stream"], d["form"], d["files"] = data
def _get_stream_for_parsing(self):
"""This is the same as accessing :attr:`stream` with the difference
that if it finds cached data from calling :meth:`get_data` first it
will create a new stream out of the cached data.
.. versionadded:: 0.9.3
"""
cached_data = getattr(self, "_cached_data", None)
if cached_data is not None:
return BytesIO(cached_data)
return self.stream
def close(self):
"""Closes associated resources of this request object. This
closes all file handles explicitly. You can also use the request
object in a with statement which will automatically close it.
.. versionadded:: 0.9
"""
files = self.__dict__.get("files")
for _key, value in iter_multi_items(files or ()):
value.close()
def __enter__(self):
return self
def __exit__(self, exc_type, exc_value, tb):
self.close()
@cached_property
def stream(self):
"""
If the incoming form data was not encoded with a known mimetype
the data is stored unmodified in this stream for consumption. Most
of the time it is a better idea to use :attr:`data` which will give
you that data as a string. The stream only returns the data once.
Unlike :attr:`input_stream` this stream is properly guarded that you
can't accidentally read past the length of the input. Werkzeug will
internally always refer to this stream to read data which makes it
possible to wrap this object with a stream that does filtering.
.. versionchanged:: 0.9
This stream is now always available but might be consumed by the
form parser later on. Previously the stream was only set if no
parsing happened.
"""
_assert_not_shallow(self)
return get_input_stream(self.environ)
input_stream = environ_property(
"wsgi.input",
"""The WSGI input stream.
In general it's a bad idea to use this one because you can
easily read past the boundary. Use the :attr:`stream`
instead.""",
)
@cached_property
def args(self):
"""The parsed URL parameters (the part in the URL after the question
mark).
By default an
:class:`~werkzeug.datastructures.ImmutableMultiDict`
is returned from this function. This can be changed by setting
:attr:`parameter_storage_class` to a different type. This might
be necessary if the order of the form data is important.
"""
return url_decode(
wsgi_get_bytes(self.environ.get("QUERY_STRING", "")),
self.url_charset,
errors=self.encoding_errors,
cls=self.parameter_storage_class,
)
@cached_property
def data(self):
"""
Contains the incoming request data as string in case it came with
a mimetype Werkzeug does not handle.
"""
if self.disable_data_descriptor:
raise AttributeError("data descriptor is disabled")
# XXX: this should eventually be deprecated.
# We trigger form data parsing first which means that the descriptor
# will not cache the data that would otherwise be .form or .files
# data. This restores the behavior that was there in Werkzeug
# before 0.9. New code should use :meth:`get_data` explicitly as
# this will make behavior explicit.
return self.get_data(parse_form_data=True)
def get_data(self, cache=True, as_text=False, parse_form_data=False):
"""This reads the buffered incoming data from the client into one
bytestring. By default this is cached but that behavior can be
changed by setting `cache` to `False`.
Usually it's a bad idea to call this method without checking the
content length first as a client could send dozens of megabytes or more
to cause memory problems on the server.
Note that if the form data was already parsed this method will not
return anything as form data parsing does not cache the data like
this method does. To implicitly invoke form data parsing function
set `parse_form_data` to `True`. When this is done the return value
of this method will be an empty string if the form parser handles
the data. This generally is not necessary as if the whole data is
cached (which is the default) the form parser will used the cached
data to parse the form data. Please be generally aware of checking
the content length first in any case before calling this method
to avoid exhausting server memory.
If `as_text` is set to `True` the return value will be a decoded
unicode string.
.. versionadded:: 0.9
"""
rv = getattr(self, "_cached_data", None)
if rv is None:
if parse_form_data:
self._load_form_data()
rv = self.stream.read()
if cache:
self._cached_data = rv
if as_text:
rv = rv.decode(self.charset, self.encoding_errors)
return rv
@cached_property
def form(self):
"""The form parameters. By default an
:class:`~werkzeug.datastructures.ImmutableMultiDict`
is returned from this function. This can be changed by setting
:attr:`parameter_storage_class` to a different type. This might
be necessary if the order of the form data is important.
Please keep in mind that file uploads will not end up here, but instead
in the :attr:`files` attribute.
.. versionchanged:: 0.9
Previous to Werkzeug 0.9 this would only contain form data for POST
and PUT requests.
"""
self._load_form_data()
return self.form
@cached_property
def values(self):
"""A :class:`werkzeug.datastructures.CombinedMultiDict` that combines
:attr:`args` and :attr:`form`."""
args = []
for d in self.args, self.form:
if not isinstance(d, MultiDict):
d = MultiDict(d)
args.append(d)
return CombinedMultiDict(args)
@cached_property
def files(self):
""":class:`~werkzeug.datastructures.MultiDict` object containing
all uploaded files. Each key in :attr:`files` is the name from the
````. Each value in :attr:`files` is a
Werkzeug :class:`~werkzeug.datastructures.FileStorage` object.
It basically behaves like a standard file object you know from Python,
with the difference that it also has a
:meth:`~werkzeug.datastructures.FileStorage.save` function that can
store the file on the filesystem.
Note that :attr:`files` will only contain data if the request method was
POST, PUT or PATCH and the ``