Convert watch page to flask framework

11 files changed, 2422 insertions, 0 deletions

diff --git a/python/werkzeug/wrappers/__init__.py b/python/werkzeug/wrappers/__init__.py
new file mode 100644
index 0000000..56c764a
--- /dev/null
+++ b/python/werkzeug/wrappers/__init__.py
@@ -0,0 +1,36 @@
+"""
+werkzeug.wrappers
+~~~~~~~~~~~~~~~~~
+
+The wrappers are simple request and response objects which you can
+subclass to do whatever you want them to do.  The request object contains
+the information transmitted by the client (webbrowser) and the response
+object contains all the information sent back to the browser.
+
+An important detail is that the request object is created with the WSGI
+environ and will act as high-level proxy whereas the response object is an
+actual WSGI application.
+
+Like everything else in Werkzeug these objects will work correctly with
+unicode data.  Incoming form data parsed by the response object will be
+decoded into an unicode object if possible and if it makes sense.
+
+:copyright: 2007 Pallets
+:license: BSD-3-Clause
+"""
+from .accept import AcceptMixin
+from .auth import AuthorizationMixin
+from .auth import WWWAuthenticateMixin
+from .base_request import BaseRequest
+from .base_response import BaseResponse
+from .common_descriptors import CommonRequestDescriptorsMixin
+from .common_descriptors import CommonResponseDescriptorsMixin
+from .etag import ETagRequestMixin
+from .etag import ETagResponseMixin
+from .request import PlainRequest
+from .request import Request
+from .request import StreamOnlyMixin
+from .response import Response
+from .response import ResponseStream
+from .response import ResponseStreamMixin
+from .user_agent import UserAgentMixin
diff --git a/python/werkzeug/wrappers/accept.py b/python/werkzeug/wrappers/accept.py
new file mode 100644
index 0000000..d0620a0
--- /dev/null
+++ b/python/werkzeug/wrappers/accept.py
@@ -0,0 +1,50 @@
+from ..datastructures import CharsetAccept
+from ..datastructures import LanguageAccept
+from ..datastructures import MIMEAccept
+from ..http import parse_accept_header
+from ..utils import cached_property
+
+
+class AcceptMixin(object):
+    """A mixin for classes with an :attr:`~BaseResponse.environ` attribute
+    to get all the HTTP accept headers as
+    :class:`~werkzeug.datastructures.Accept` objects (or subclasses
+    thereof).
+    """
+
+    @cached_property
+    def accept_mimetypes(self):
+        """List of mimetypes this client supports as
+        :class:`~werkzeug.datastructures.MIMEAccept` object.
+        """
+        return parse_accept_header(self.environ.get("HTTP_ACCEPT"), MIMEAccept)
+
+    @cached_property
+    def accept_charsets(self):
+        """List of charsets this client supports as
+        :class:`~werkzeug.datastructures.CharsetAccept` object.
+        """
+        return parse_accept_header(
+            self.environ.get("HTTP_ACCEPT_CHARSET"), CharsetAccept
+        )
+
+    @cached_property
+    def accept_encodings(self):
+        """List of encodings this client accepts.  Encodings in a HTTP term
+        are compression encodings such as gzip.  For charsets have a look at
+        :attr:`accept_charset`.
+        """
+        return parse_accept_header(self.environ.get("HTTP_ACCEPT_ENCODING"))
+
+    @cached_property
+    def accept_languages(self):
+        """List of languages this client accepts as
+        :class:`~werkzeug.datastructures.LanguageAccept` object.
+
+        .. versionchanged 0.5
+           In previous versions this was a regular
+           :class:`~werkzeug.datastructures.Accept` object.
+        """
+        return parse_accept_header(
+            self.environ.get("HTTP_ACCEPT_LANGUAGE"), LanguageAccept
+        )
diff --git a/python/werkzeug/wrappers/auth.py b/python/werkzeug/wrappers/auth.py
new file mode 100644
index 0000000..714f755
--- /dev/null
+++ b/python/werkzeug/wrappers/auth.py
@@ -0,0 +1,33 @@
+from ..http import parse_authorization_header
+from ..http import parse_www_authenticate_header
+from ..utils import cached_property
+
+
+class AuthorizationMixin(object):
+    """Adds an :attr:`authorization` property that represents the parsed
+    value of the `Authorization` header as
+    :class:`~werkzeug.datastructures.Authorization` object.
+    """
+
+    @cached_property
+    def authorization(self):
+        """The `Authorization` object in parsed form."""
+        header = self.environ.get("HTTP_AUTHORIZATION")
+        return parse_authorization_header(header)
+
+
+class WWWAuthenticateMixin(object):
+    """Adds a :attr:`www_authenticate` property to a response object."""
+
+    @property
+    def www_authenticate(self):
+        """The `WWW-Authenticate` header in a parsed form."""
+
+        def on_update(www_auth):
+            if not www_auth and "www-authenticate" in self.headers:
+                del self.headers["www-authenticate"]
+            elif www_auth:
+                self.headers["WWW-Authenticate"] = www_auth.to_header()
+
+        header = self.headers.get("www-authenticate")
+        return parse_www_authenticate_header(header, on_update)
diff --git a/python/werkzeug/wrappers/base_request.py b/python/werkzeug/wrappers/base_request.py
new file mode 100644
index 0000000..41e8aad
--- /dev/null
+++ b/python/werkzeug/wrappers/base_request.py
@@ -0,0 +1,693 @@
+import warnings
+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 ImmutableTypeConversionDict
+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_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 </unicode>` 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.
+    #: By default an
+    #: :class:`~werkzeug.datastructures.ImmutableTypeConversionDict` is used
+    #: (for example for :attr:`cookies`).
+    #:
+    #: .. versionadded:: 0.6
+    dict_storage_class = ImmutableTypeConversionDict
+
+    #: 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 first
+        argument.  This works like the :func:`responder` decorator but the
+        function is passed the request object as first 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 methods and standalone WSGI 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
+        ``<input type="file" name="">``.  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 ``<form>`` that posted to the request had
+        ``enctype="multipart/form-data"``.  It will be empty otherwise.
+
+        See the :class:`~werkzeug.datastructures.MultiDict` /
+        :class:`~werkzeug.datastructures.FileStorage` documentation for
+        more details about the used data structure.
+        """
+        self._load_form_data()
+        return self.files
+
+    @cached_property
+    def cookies(self):
+        """A :class:`dict` with the contents of all cookies transmitted with
+        the request."""
+        return parse_cookie(
+            self.environ,
+            self.charset,
+            self.encoding_errors,
+            cls=self.dict_storage_class,
+        )
+
+    @cached_property
+    def headers(self):
+        """The headers from the WSGI environ as immutable
+        :class:`~werkzeug.datastructures.EnvironHeaders`.
+        """
+        return EnvironHeaders(self.environ)
+
+    @cached_property
+    def path(self):
+        """Requested path as unicode.  This works a bit like the regular path
+        info in the WSGI environment but will always include a leading slash,
+        even if the URL root is accessed.
+        """
+        raw_path = wsgi_decoding_dance(
+            self.environ.get("PATH_INFO") or "", self.charset, self.encoding_errors
+        )
+        return "/" + raw_path.lstrip("/")
+
+    @cached_property
+    def full_path(self):
+        """Requested path as unicode, including the query string."""
+        return self.path + u"?" + to_unicode(self.query_string, self.url_charset)
+
+    @cached_property
+    def script_root(self):
+        """The root path of the script without the trailing slash."""
+        raw_path = wsgi_decoding_dance(
+            self.environ.get("SCRIPT_NAME") or "", self.charset, self.encoding_errors
+        )
+        return raw_path.rstrip("/")
+
+    @cached_property
+    def url(self):
+        """The reconstructed current URL as IRI.
+        See also: :attr:`trusted_hosts`.
+        """
+        return get_current_url(self.environ, trusted_hosts=self.trusted_hosts)
+
+    @cached_property
+    def base_url(self):
+        """Like :attr:`url` but without the querystring
+        See also: :attr:`trusted_hosts`.
+        """
+        return get_current_url(
+            self.environ, strip_querystring=True, trusted_hosts=self.trusted_hosts
+        )
+
+    @cached_property
+    def url_root(self):
+        """The full URL root (with hostname), this is the application
+        root as IRI.
+        See also: :attr:`trusted_hosts`.
+        """
+        return get_current_url(self.environ, True, trusted_hosts=self.trusted_hosts)
+
+    @cached_property
+    def host_url(self):
+        """Just the host with scheme as IRI.
+        See also: :attr:`trusted_hosts`.
+        """
+        return get_current_url(
+            self.environ, host_only=True, trusted_hosts=self.trusted_hosts
+        )
+
+    @cached_property
+    def host(self):
+        """Just the host including the port if available.
+        See also: :attr:`trusted_hosts`.
+        """
+        return get_host(self.environ, trusted_hosts=self.trusted_hosts)
+
+    query_string = environ_property(
+        "QUERY_STRING",
+        "",
+        read_only=True,
+        load_func=wsgi_get_bytes,
+        doc="The URL parameters as raw bytestring.",
+    )
+    method = environ_property(
+        "REQUEST_METHOD",
+        "GET",
+        read_only=True,
+        load_func=lambda x: x.upper(),
+        doc="The request method. (For example ``'GET'`` or ``'POST'``).",
+    )
+
+    @cached_property
+    def access_route(self):
+        """If a forwarded header exists this is a list of all ip addresses
+        from the client ip to the last proxy server.
+        """
+        if "HTTP_X_FORWARDED_FOR" in self.environ:
+            addr = self.environ["HTTP_X_FORWARDED_FOR"].split(",")
+            return self.list_storage_class([x.strip() for x in addr])
+        elif "REMOTE_ADDR" in self.environ:
+            return self.list_storage_class([self.environ["REMOTE_ADDR"]])
+        return self.list_storage_class()
+
+    @property
+    def remote_addr(self):
+        """The remote address of the client."""
+        return self.environ.get("REMOTE_ADDR")
+
+    remote_user = environ_property(
+        "REMOTE_USER",
+        doc="""If the server supports user authentication, and the
+        script is protected, this attribute contains the username the
+        user has authenticated as.""",
+    )
+
+    scheme = environ_property(
+        "wsgi.url_scheme",
+        doc="""
+        URL scheme (http or https).
+
+        .. versionadded:: 0.7""",
+    )
+
+    @property
+    def is_xhr(self):
+        """True if the request was triggered via a JavaScript XMLHttpRequest.
+        This only works with libraries that support the ``X-Requested-With``
+        header and set it to "XMLHttpRequest".  Libraries that do that are
+        prototype, jQuery and Mochikit and probably some more.
+
+        .. deprecated:: 0.13
+            ``X-Requested-With`` is not standard and is unreliable. You
+            may be able to use :attr:`AcceptMixin.accept_mimetypes`
+            instead.
+        """
+        warnings.warn(
+            "'Request.is_xhr' is deprecated as of version 0.13 and will"
+            " be removed in version 1.0. The 'X-Requested-With' header"
+            " is not standard and is unreliable. You may be able to use"
+            " 'accept_mimetypes' instead.",
+            DeprecationWarning,
+            stacklevel=2,
+        )
+        return self.environ.get("HTTP_X_REQUESTED_WITH", "").lower() == "xmlhttprequest"
+
+    is_secure = property(
+        lambda self: self.environ["wsgi.url_scheme"] == "https",
+        doc="`True` if the request is secure.",
+    )
+    is_multithread = environ_property(
+        "wsgi.multithread",
+        doc="""boolean that is `True` if the application is served by a
+        multithreaded WSGI server.""",
+    )
+    is_multiprocess = environ_property(
+        "wsgi.multiprocess",
+        doc="""boolean that is `True` if the application is served by a
+        WSGI server that spawns multiple processes.""",
+    )
+    is_run_once = environ_property(
+        "wsgi.run_once",
+        doc="""boolean that is `True` if the application will be
+        executed only once in a process lifetime.  This is the case for
+        CGI for example, but it's not guaranteed that the execution only
+        happens one time.""",
+    )
+
+
+def _assert_not_shallow(request):
+    if request.shallow:
+        raise RuntimeError(
+            "A shallow request tried to consume form data. If you really"
+            " want to do that, set `shallow` to False."
+        )
diff --git a/python/werkzeug/wrappers/base_response.py b/python/werkzeug/wrappers/base_response.py
new file mode 100644
index 0000000..d944a7d
--- /dev/null
+++ b/python/werkzeug/wrappers/base_response.py
@@ -0,0 +1,702 @@
+import warnings
+
+from .._compat import integer_types
+from .._compat import string_types
+from .._compat import text_type
+from .._compat import to_bytes
+from .._compat import to_native
+from ..datastructures import Headers
+from ..http import dump_cookie
+from ..http import HTTP_STATUS_CODES
+from ..http import remove_entity_headers
+from ..urls import iri_to_uri
+from ..urls import url_join
+from ..utils import get_content_type
+from ..wsgi import ClosingIterator
+from ..wsgi import get_current_url
+
+
+def _run_wsgi_app(*args):
+    """This function replaces itself to ensure that the test module is not
+    imported unless required.  DO NOT USE!
+    """
+    global _run_wsgi_app
+    from ..test import run_wsgi_app as _run_wsgi_app
+
+    return _run_wsgi_app(*args)
+
+
+def _warn_if_string(iterable):
+    """Helper for the response objects to check if the iterable returned
+    to the WSGI server is not a string.
+    """
+    if isinstance(iterable, string_types):
+        warnings.warn(
+            "Response iterable was set to a string. This will appear to"
+            " work but means that the server will send the data to the"
+            " client one character at a time. This is almost never"
+            " intended behavior, use 'response.data' to assign strings"
+            " to the response object.",
+            stacklevel=2,
+        )
+
+
+def _iter_encoded(iterable, charset):
+    for item in iterable:
+        if isinstance(item, text_type):
+            yield item.encode(charset)
+        else:
+            yield item
+
+
+def _clean_accept_ranges(accept_ranges):
+    if accept_ranges is True:
+        return "bytes"
+    elif accept_ranges is False:
+        return "none"
+    elif isinstance(accept_ranges, text_type):
+        return to_native(accept_ranges)
+    raise ValueError("Invalid accept_ranges value")
+
+
+class BaseResponse(object):
+    """Base response class.  The most important fact about a response object
+    is that it's a regular WSGI application.  It's initialized with a couple
+    of response parameters (headers, body, status code etc.) and will start a
+    valid WSGI response when called with the environ and start response
+    callable.
+
+    Because it's a WSGI application itself processing usually ends before the
+    actual response is sent to the server.  This helps debugging systems
+    because they can catch all the exceptions before responses are started.
+
+    Here a small example WSGI application that takes advantage of the
+    response objects::
+
+        from werkzeug.wrappers import BaseResponse as Response
+
+        def index():
+            return Response('Index page')
+
+        def application(environ, start_response):
+            path = environ.get('PATH_INFO') or '/'
+            if path == '/':
+                response = index()
+            else:
+                response = Response('Not Found', status=404)
+            return response(environ, start_response)
+
+    Like :class:`BaseRequest` which object is lacking a lot of functionality
+    implemented in mixins.  This gives you a better control about the actual
+    API of your response objects, so you can create subclasses and add custom
+    functionality.  A full featured response object is available as
+    :class:`Response` which implements a couple of useful mixins.
+
+    To enforce a new type of already existing responses you can use the
+    :meth:`force_type` method.  This is useful if you're working with different
+    subclasses of response objects and you want to post process them with a
+    known interface.
+
+    Per default the response object will assume all the text data is `utf-8`
+    encoded.  Please refer to :doc:`the unicode chapter </unicode>` for more
+    details about customizing the behavior.
+
+    Response can be any kind of iterable or string.  If it's a string it's
+    considered being an iterable with one item which is the string passed.
+    Headers can be a list of tuples or a
+    :class:`~werkzeug.datastructures.Headers` object.
+
+    Special note for `mimetype` and `content_type`:  For most mime types
+    `mimetype` and `content_type` work the same, the difference affects
+    only 'text' mimetypes.  If the mimetype passed with `mimetype` is a
+    mimetype starting with `text/`, the charset parameter of the response
+    object is appended to it.  In contrast the `content_type` parameter is
+    always added as header unmodified.
+
+    .. versionchanged:: 0.5
+       the `direct_passthrough` parameter was added.
+
+    :param response: a string or response iterable.
+    :param status: a string with a status or an integer with the status code.
+    :param headers: a list of headers or a
+                    :class:`~werkzeug.datastructures.Headers` object.
+    :param mimetype: the mimetype for the response.  See notice above.
+    :param content_type: the content type for the response.  See notice above.
+    :param direct_passthrough: if set to `True` :meth:`iter_encoded` is not
+                               called before iteration which makes it
+                               possible to pass special iterators through
+                               unchanged (see :func:`wrap_file` for more
+                               details.)
+    """
+
+    #: the charset of the response.
+    charset = "utf-8"
+
+    #: the default status if none is provided.
+    default_status = 200
+
+    #: the default mimetype if none is provided.
+    default_mimetype = "text/plain"
+
+    #: if set to `False` accessing properties on the response object will
+    #: not try to consume the response iterator and convert it into a list.
+    #:
+    #: .. versionadded:: 0.6.2
+    #:
+    #:    That attribute was previously called `implicit_seqence_conversion`.
+    #:    (Notice the typo).  If you did use this feature, you have to adapt
+    #:    your code to the name change.
+    implicit_sequence_conversion = True
+
+    #: Should this response object correct the location header to be RFC
+    #: conformant?  This is true by default.
+    #:
+    #: .. versionadded:: 0.8
+    autocorrect_location_header = True
+
+    #: Should this response object automatically set the content-length
+    #: header if possible?  This is true by default.
+    #:
+    #: .. versionadded:: 0.8
+    automatically_set_content_length = True
+
+    #: Warn if a cookie header exceeds this size. The default, 4093, should be
+    #: safely `supported by most browsers <cookie_>`_. A cookie larger than
+    #: this size will still be sent, but it may be ignored or handled
+    #: incorrectly by some browsers. Set to 0 to disable this check.
+    #:
+    #: .. versionadded:: 0.13
+    #:
+    #: .. _`cookie`: http://browsercookielimits.squawky.net/
+    max_cookie_size = 4093
+
+    def __init__(
+        self,
+        response=None,
+        status=None,
+        headers=None,
+        mimetype=None,
+        content_type=None,
+        direct_passthrough=False,
+    ):
+        if isinstance(headers, Headers):
+            self.headers = headers
+        elif not headers:
+            self.headers = Headers()
+        else:
+            self.headers = Headers(headers)
+
+        if content_type is None:
+            if mimetype is None and "content-type" not in self.headers:
+                mimetype = self.default_mimetype
+            if mimetype is not None:
+                mimetype = get_content_type(mimetype, self.charset)
+            content_type = mimetype
+        if content_type is not None:
+            self.headers["Content-Type"] = content_type
+        if status is None:
+            status = self.default_status
+        if isinstance(status, integer_types):
+            self.status_code = status
+        else:
+            self.status = status
+
+        self.direct_passthrough = direct_passthrough
+        self._on_close = []
+
+        # we set the response after the headers so that if a class changes
+        # the charset attribute, the data is set in the correct charset.
+        if response is None:
+            self.response = []
+        elif isinstance(response, (text_type, bytes, bytearray)):
+            self.set_data(response)
+        else:
+            self.response = response
+
+    def call_on_close(self, func):
+        """Adds a function to the internal list of functions that should
+        be called as part of closing down the response.  Since 0.7 this
+        function also returns the function that was passed so that this
+        can be used as a decorator.
+
+        .. versionadded:: 0.6
+        """
+        self._on_close.append(func)
+        return func
+
+    def __repr__(self):
+        if self.is_sequence:
+            body_info = "%d bytes" % sum(map(len, self.iter_encoded()))
+        else:
+            body_info = "streamed" if self.is_streamed else "likely-streamed"
+        return "<%s %s [%s]>" % (self.__class__.__name__, body_info, self.status)
+
+    @classmethod
+    def force_type(cls, response, environ=None):
+        """Enforce that the WSGI response is a response object of the current
+        type.  Werkzeug will use the :class:`BaseResponse` internally in many
+        situations like the exceptions.  If you call :meth:`get_response` on an
+        exception you will get back a regular :class:`BaseResponse` object, even
+        if you are using a custom subclass.
+
+        This method can enforce a given response type, and it will also
+        convert arbitrary WSGI callables into response objects if an environ
+        is provided::
+
+            # convert a Werkzeug response object into an instance of the
+            # MyResponseClass subclass.
+            response = MyResponseClass.force_type(response)
+
+            # convert any WSGI application into a response object
+            response = MyResponseClass.force_type(response, environ)
+
+        This is especially useful if you want to post-process responses in
+        the main dispatcher and use functionality provided by your subclass.
+
+        Keep in mind that this will modify response objects in place if
+        possible!
+
+        :param response: a response object or wsgi application.
+        :param environ: a WSGI environment object.
+        :return: a response object.
+        """
+        if not isinstance(response, BaseResponse):
+            if environ is None:
+                raise TypeError(
+                    "cannot convert WSGI application into response"
+                    " objects without an environ"
+                )
+            response = BaseResponse(*_run_wsgi_app(response, environ))
+        response.__class__ = cls
+        return response
+
+    @classmethod
+    def from_app(cls, app, environ, buffered=False):
+        """Create a new response object from an application output.  This
+        works best if you pass it an application that returns a generator all
+        the time.  Sometimes applications may use the `write()` callable
+        returned by the `start_response` function.  This tries to resolve such
+        edge cases automatically.  But if you don't get the expected output
+        you should set `buffered` to `True` which enforces buffering.
+
+        :param app: the WSGI application to execute.
+        :param environ: the WSGI environment to execute against.
+        :param buffered: set to `True` to enforce buffering.
+        :return: a response object.
+        """
+        return cls(*_run_wsgi_app(app, environ, buffered))
+
+    def _get_status_code(self):
+        return self._status_code
+
+    def _set_status_code(self, code):
+        self._status_code = code
+        try:
+            self._status = "%d %s" % (code, HTTP_STATUS_CODES[code].upper())
+        except KeyError:
+            self._status = "%d UNKNOWN" % code
+
+    status_code = property(
+        _get_status_code, _set_status_code, doc="The HTTP Status code as number"
+    )
+    del _get_status_code, _set_status_code
+
+    def _get_status(self):
+        return self._status
+
+    def _set_status(self, value):
+        try:
+            self._status = to_native(value)
+        except AttributeError:
+            raise TypeError("Invalid status argument")
+
+        try:
+            self._status_code = int(self._status.split(None, 1)[0])
+        except ValueError:
+            self._status_code = 0
+            self._status = "0 %s" % self._status
+        except IndexError:
+            raise ValueError("Empty status argument")
+
+    status = property(_get_status, _set_status, doc="The HTTP Status code")
+    del _get_status, _set_status
+
+    def get_data(self, as_text=False):
+        """The string representation of the request body.  Whenever you call
+        this property the request iterable is encoded and flattened.  This
+        can lead to unwanted behavior if you stream big data.
+
+        This behavior can be disabled by setting
+        :attr:`implicit_sequence_conversion` to `False`.
+
+        If `as_text` is set to `True` the return value will be a decoded
+        unicode string.
+
+        .. versionadded:: 0.9
+        """
+        self._ensure_sequence()
+        rv = b"".join(self.iter_encoded())
+        if as_text:
+            rv = rv.decode(self.charset)
+        return rv
+
+    def set_data(self, value):
+        """Sets a new string as response.  The value set must either by a
+        unicode or bytestring.  If a unicode string is set it's encoded
+        automatically to the charset of the response (utf-8 by default).
+
+        .. versionadded:: 0.9
+        """
+        # if an unicode string is set, it's encoded directly so that we
+        # can set the content length
+        if isinstance(value, text_type):
+            value = value.encode(self.charset)
+        else:
+            value = bytes(value)
+        self.response = [value]
+        if self.automatically_set_content_length:
+            self.headers["Content-Length"] = str(len(value))
+
+    data = property(
+        get_data,
+        set_data,
+        doc="A descriptor that calls :meth:`get_data` and :meth:`set_data`.",
+    )
+
+    def calculate_content_length(self):
+        """Returns the content length if available or `None` otherwise."""
+        try:
+            self._ensure_sequence()
+        except RuntimeError:
+            return None
+        return sum(len(x) for x in self.iter_encoded())
+
+    def _ensure_sequence(self, mutable=False):
+        """This method can be called by methods that need a sequence.  If
+        `mutable` is true, it will also ensure that the response sequence
+        is a standard Python list.
+
+        .. versionadded:: 0.6
+        """
+        if self.is_sequence:
+            # if we need a mutable object, we ensure it's a list.
+            if mutable and not isinstance(self.response, list):
+                self.response = list(self.response)
+            return
+        if self.direct_passthrough:
+            raise RuntimeError(
+                "Attempted implicit sequence conversion but the"
+                " response object is in direct passthrough mode."
+            )
+        if not self.implicit_sequence_conversion:
+            raise RuntimeError(
+                "The response object required the iterable to be a"
+                " sequence, but the implicit conversion was disabled."
+                " Call make_sequence() yourself."
+            )
+        self.make_sequence()
+
+    def make_sequence(self):
+        """Converts the response iterator in a list.  By default this happens
+        automatically if required.  If `implicit_sequence_conversion` is
+        disabled, this method is not automatically called and some properties
+        might raise exceptions.  This also encodes all the items.
+
+        .. versionadded:: 0.6
+        """
+        if not self.is_sequence:
+            # if we consume an iterable we have to ensure that the close
+            # method of the iterable is called if available when we tear
+            # down the response
+            close = getattr(self.response, "close", None)
+            self.response = list(self.iter_encoded())
+            if close is not None:
+                self.call_on_close(close)
+
+    def iter_encoded(self):
+        """Iter the response encoded with the encoding of the response.
+        If the response object is invoked as WSGI application the return
+        value of this method is used as application iterator unless
+        :attr:`direct_passthrough` was activated.
+        """
+        if __debug__:
+            _warn_if_string(self.response)
+        # Encode in a separate function so that self.response is fetched
+        # early.  This allows us to wrap the response with the return
+        # value from get_app_iter or iter_encoded.
+        return _iter_encoded(self.response, self.charset)
+
+    def set_cookie(
+        self,
+        key,
+        value="",
+        max_age=None,
+        expires=None,
+        path="/",
+        domain=None,
+        secure=False,
+        httponly=False,
+        samesite=None,
+    ):
+        """Sets a cookie. The parameters are the same as in the cookie `Morsel`
+        object in the Python standard library but it accepts unicode data, too.
+
+        A warning is raised if the size of the cookie header exceeds
+        :attr:`max_cookie_size`, but the header will still be set.
+
+        :param key: the key (name) of the cookie to be set.
+        :param value: the value of the cookie.
+        :param max_age: should be a number of seconds, or `None` (default) if
+                        the cookie should last only as long as the client's
+                        browser session.
+        :param expires: should be a `datetime` object or UNIX timestamp.
+        :param path: limits the cookie to a given path, per default it will
+                     span the whole domain.
+        :param domain: if you want to set a cross-domain cookie.  For example,
+                       ``domain=".example.com"`` will set a cookie that is
+                       readable by the domain ``www.example.com``,
+                       ``foo.example.com`` etc.  Otherwise, a cookie will only
+                       be readable by the domain that set it.
+        :param secure: If `True`, the cookie will only be available via HTTPS
+        :param httponly: disallow JavaScript to access the cookie.  This is an
+                         extension to the cookie standard and probably not
+                         supported by all browsers.
+        :param samesite: Limits the scope of the cookie such that it will only
+                         be attached to requests if those requests are
+                         "same-site".
+        """
+        self.headers.add(
+            "Set-Cookie",
+            dump_cookie(
+                key,
+                value=value,
+                max_age=max_age,
+                expires=expires,
+                path=path,
+                domain=domain,
+                secure=secure,
+                httponly=httponly,
+                charset=self.charset,
+                max_size=self.max_cookie_size,
+                samesite=samesite,
+            ),
+        )
+
+    def delete_cookie(self, key, path="/", domain=None):
+        """Delete a cookie.  Fails silently if key doesn't exist.
+
+        :param key: the key (name) of the cookie to be deleted.
+        :param path: if the cookie that should be deleted was limited to a
+                     path, the path has to be defined here.
+        :param domain: if the cookie that should be deleted was limited to a
+                       domain, that domain has to be defined here.
+        """
+        self.set_cookie(key, expires=0, max_age=0, path=path, domain=domain)
+
+    @property
+    def is_streamed(self):
+        """If the response is streamed (the response is not an iterable with
+        a length information) this property is `True`.  In this case streamed
+        means that there is no information about the number of iterations.
+        This is usually `True` if a generator is passed to the response object.
+
+        This is useful for checking before applying some sort of post
+        filtering that should not take place for streamed responses.
+        """
+        try:
+            len(self.response)
+        except (TypeError, AttributeError):
+            return True
+        return False
+
+    @property
+    def is_sequence(self):
+        """If the iterator is buffered, this property will be `True`.  A
+        response object will consider an iterator to be buffered if the
+        response attribute is a list or tuple.
+
+        .. versionadded:: 0.6
+        """
+        return isinstance(self.response, (tuple, list))
+
+    def close(self):
+        """Close the wrapped response if possible.  You can also use the object
+        in a with statement which will automatically close it.
+
+        .. versionadded:: 0.9
+           Can now be used in a with statement.
+        """
+        if hasattr(self.response, "close"):
+            self.response.close()
+        for func in self._on_close:
+            func()
+
+    def __enter__(self):
+        return self
+
+    def __exit__(self, exc_type, exc_value, tb):
+        self.close()
+
+    def freeze(self):
+        """Call this method if you want to make your response object ready for
+        being pickled.  This buffers the generator if there is one.  It will
+        also set the `Content-Length` header to the length of the body.
+
+        .. versionchanged:: 0.6
+           The `Content-Length` header is now set.
+        """
+        # we explicitly set the length to a list of the *encoded* response
+        # iterator.  Even if the implicit sequence conversion is disabled.
+        self.response = list(self.iter_encoded())
+        self.headers["Content-Length"] = str(sum(map(len, self.response)))
+
+    def get_wsgi_headers(self, environ):
+        """This is automatically called right before the response is started
+        and returns headers modified for the given environment.  It returns a
+        copy of the headers from the response with some modifications applied
+        if necessary.
+
+        For example the location header (if present) is joined with the root
+        URL of the environment.  Also the content length is automatically set
+        to zero here for certain status codes.
+
+        .. versionchanged:: 0.6
+           Previously that function was called `fix_headers` and modified
+           the response object in place.  Also since 0.6, IRIs in location
+           and content-location headers are handled properly.
+
+           Also starting with 0.6, Werkzeug will attempt to set the content
+           length if it is able to figure it out on its own.  This is the
+           case if all the strings in the response iterable are already
+           encoded and the iterable is buffered.
+
+        :param environ: the WSGI environment of the request.
+        :return: returns a new :class:`~werkzeug.datastructures.Headers`
+                 object.
+        """
+        headers = Headers(self.headers)
+        location = None
+        content_location = None
+        content_length = None
+        status = self.status_code
+
+        # iterate over the headers to find all values in one go.  Because
+        # get_wsgi_headers is used each response that gives us a tiny
+        # speedup.
+        for key, value in headers:
+            ikey = key.lower()
+            if ikey == u"location":
+                location = value
+            elif ikey == u"content-location":
+                content_location = value
+            elif ikey == u"content-length":
+                content_length = value
+
+        # make sure the location header is an absolute URL
+        if location is not None:
+            old_location = location
+            if isinstance(location, text_type):
+                # Safe conversion is necessary here as we might redirect
+                # to a broken URI scheme (for instance itms-services).
+                location = iri_to_uri(location, safe_conversion=True)
+
+            if self.autocorrect_location_header:
+                current_url = get_current_url(environ, strip_querystring=True)
+                if isinstance(current_url, text_type):
+                    current_url = iri_to_uri(current_url)
+                location = url_join(current_url, location)
+            if location != old_location:
+                headers["Location"] = location
+
+        # make sure the content location is a URL
+        if content_location is not None and isinstance(content_location, text_type):
+            headers["Content-Location"] = iri_to_uri(content_location)
+
+        if 100 <= status < 200 or status == 204:
+            # Per section 3.3.2 of RFC 7230, "a server MUST NOT send a
+            # Content-Length header field in any response with a status
+            # code of 1xx (Informational) or 204 (No Content)."
+            headers.remove("Content-Length")
+        elif status == 304:
+            remove_entity_headers(headers)
+
+        # if we can determine the content length automatically, we
+        # should try to do that.  But only if this does not involve
+        # flattening the iterator or encoding of unicode strings in
+        # the response.  We however should not do that if we have a 304
+        # response.
+        if (
+            self.automatically_set_content_length
+            and self.is_sequence
+            and content_length is None
+            and status not in (204, 304)
+            and not (100 <= status < 200)
+        ):
+            try:
+                content_length = sum(len(to_bytes(x, "ascii")) for x in self.response)
+            except UnicodeError:
+                # aha, something non-bytestringy in there, too bad, we
+                # can't safely figure out the length of the response.
+                pass
+            else:
+                headers["Content-Length"] = str(content_length)
+
+        return headers
+
+    def get_app_iter(self, environ):
+        """Returns the application iterator for the given environ.  Depending
+        on the request method and the current status code the return value
+        might be an empty response rather than the one from the response.
+
+        If the request method is `HEAD` or the status code is in a range
+        where the HTTP specification requires an empty response, an empty
+        iterable is returned.
+
+        .. versionadded:: 0.6
+
+        :param environ: the WSGI environment of the request.
+        :return: a response iterable.
+        """
+        status = self.status_code
+        if (
+            environ["REQUEST_METHOD"] == "HEAD"
+            or 100 <= status < 200
+            or status in (204, 304)
+        ):
+            iterable = ()
+        elif self.direct_passthrough:
+            if __debug__:
+                _warn_if_string(self.response)
+            return self.response
+        else:
+            iterable = self.iter_encoded()
+        return ClosingIterator(iterable, self.close)
+
+    def get_wsgi_response(self, environ):
+        """Returns the final WSGI response as tuple.  The first item in
+        the tuple is the application iterator, the second the status and
+        the third the list of headers.  The response returned is created
+        specially for the given environment.  For example if the request
+        method in the WSGI environment is ``'HEAD'`` the response will
+        be empty and only the headers and status code will be present.
+
+        .. versionadded:: 0.6
+
+        :param environ: the WSGI environment of the request.
+        :return: an ``(app_iter, status, headers)`` tuple.
+        """
+        headers = self.get_wsgi_headers(environ)
+        app_iter = self.get_app_iter(environ)
+        return app_iter, self.status, headers.to_wsgi_list()
+
+    def __call__(self, environ, start_response):
+        """Process this response as WSGI application.
+
+        :param environ: the WSGI environment.
+        :param start_response: the response callable provided by the WSGI
+                               server.
+        :return: an application iterator
+        """
+        app_iter, status, headers = self.get_wsgi_response(environ)
+        start_response(status, headers)
+        return app_iter
diff --git a/python/werkzeug/wrappers/common_descriptors.py b/python/werkzeug/wrappers/common_descriptors.py
new file mode 100644
index 0000000..e4107ee
--- /dev/null
+++ b/python/werkzeug/wrappers/common_descriptors.py
@@ -0,0 +1,322 @@
+from datetime import datetime
+from datetime import timedelta
+
+from .._compat import string_types
+from ..datastructures import CallbackDict
+from ..http import dump_age
+from ..http import dump_header
+from ..http import dump_options_header
+from ..http import http_date
+from ..http import parse_age
+from ..http import parse_date
+from ..http import parse_options_header
+from ..http import parse_set_header
+from ..utils import cached_property
+from ..utils import environ_property
+from ..utils import get_content_type
+from ..utils import header_property
+from ..wsgi import get_content_length
+
+
+class CommonRequestDescriptorsMixin(object):
+    """A mixin for :class:`BaseRequest` subclasses.  Request objects that
+    mix this class in will automatically get descriptors for a couple of
+    HTTP headers with automatic type conversion.
+
+    .. versionadded:: 0.5
+    """
+
+    content_type = environ_property(
+        "CONTENT_TYPE",
+        doc="""The Content-Type entity-header field indicates the media
+        type of the entity-body sent to the recipient or, in the case of
+        the HEAD method, the media type that would have been sent had
+        the request been a GET.""",
+    )
+
+    @cached_property
+    def content_length(self):
+        """The Content-Length entity-header field indicates the size of the
+        entity-body in bytes or, in the case of the HEAD method, the size of
+        the entity-body that would have been sent had the request been a
+        GET.
+        """
+        return get_content_length(self.environ)
+
+    content_encoding = environ_property(
+        "HTTP_CONTENT_ENCODING",
+        doc="""The Content-Encoding entity-header field is used as a
+        modifier to the media-type. When present, its value indicates
+        what additional content codings have been applied to the
+        entity-body, and thus what decoding mechanisms must be applied
+        in order to obtain the media-type referenced by the Content-Type
+        header field.
+
+        .. versionadded:: 0.9""",
+    )
+    content_md5 = environ_property(
+        "HTTP_CONTENT_MD5",
+        doc="""The Content-MD5 entity-header field, as defined in
+        RFC 1864, is an MD5 digest of the entity-body for the purpose of
+        providing an end-to-end message integrity check (MIC) of the
+        entity-body. (Note: a MIC is good for detecting accidental
+        modification of the entity-body in transit, but is not proof
+        against malicious attacks.)
+
+        .. versionadded:: 0.9""",
+    )
+    referrer = environ_property(
+        "HTTP_REFERER",
+        doc="""The Referer[sic] request-header field allows the client
+        to specify, for the server's benefit, the address (URI) of the
+        resource from which the Request-URI was obtained (the
+        "referrer", although the header field is misspelled).""",
+    )
+    date = environ_property(
+        "HTTP_DATE",
+        None,
+        parse_date,
+        doc="""The Date general-header field represents the date and
+        time at which the message was originated, having the same
+        semantics as orig-date in RFC 822.""",
+    )
+    max_forwards = environ_property(
+        "HTTP_MAX_FORWARDS",
+        None,
+        int,
+        doc="""The Max-Forwards request-header field provides a
+        mechanism with the TRACE and OPTIONS methods to limit the number
+        of proxies or gateways that can forward the request to the next
+        inbound server.""",
+    )
+
+    def _parse_content_type(self):
+        if not hasattr(self, "_parsed_content_type"):
+            self._parsed_content_type = parse_options_header(
+                self.environ.get("CONTENT_TYPE", "")
+            )
+
+    @property
+    def mimetype(self):
+        """Like :attr:`content_type`, but without parameters (eg, without
+        charset, type etc.) and always lowercase.  For example if the content
+        type is ``text/HTML; charset=utf-8`` the mimetype would be
+        ``'text/html'``.
+        """
+        self._parse_content_type()
+        return self._parsed_content_type[0].lower()
+
+    @property
+    def mimetype_params(self):
+        """The mimetype parameters as dict.  For example if the content
+        type is ``text/html; charset=utf-8`` the params would be
+        ``{'charset': 'utf-8'}``.
+        """
+        self._parse_content_type()
+        return self._parsed_content_type[1]
+
+    @cached_property
+    def pragma(self):
+        """The Pragma general-header field is used to include
+        implementation-specific directives that might apply to any recipient
+        along the request/response chain.  All pragma directives specify
+        optional behavior from the viewpoint of the protocol; however, some
+        systems MAY require that behavior be consistent with the directives.
+        """
+        return parse_set_header(self.environ.get("HTTP_PRAGMA", ""))
+
+
+class CommonResponseDescriptorsMixin(object):
+    """A mixin for :class:`BaseResponse` subclasses.  Response objects that
+    mix this class in will automatically get descriptors for a couple of
+    HTTP headers with automatic type conversion.
+    """
+
+    @property
+    def mimetype(self):
+        """The mimetype (content type without charset etc.)"""
+        ct = self.headers.get("content-type")
+        if ct:
+            return ct.split(";")[0].strip()
+
+    @mimetype.setter
+    def mimetype(self, value):
+        self.headers["Content-Type"] = get_content_type(value, self.charset)
+
+    @property
+    def mimetype_params(self):
+        """The mimetype parameters as dict. For example if the
+        content type is ``text/html; charset=utf-8`` the params would be
+        ``{'charset': 'utf-8'}``.
+
+        .. versionadded:: 0.5
+        """
+
+        def on_update(d):
+            self.headers["Content-Type"] = dump_options_header(self.mimetype, d)
+
+        d = parse_options_header(self.headers.get("content-type", ""))[1]
+        return CallbackDict(d, on_update)
+
+    location = header_property(
+        "Location",
+        doc="""The Location response-header field is used to redirect
+        the recipient to a location other than the Request-URI for
+        completion of the request or identification of a new
+        resource.""",
+    )
+    age = header_property(
+        "Age",
+        None,
+        parse_age,
+        dump_age,
+        doc="""The Age response-header field conveys the sender's
+        estimate of the amount of time since the response (or its
+        revalidation) was generated at the origin server.
+
+        Age values are non-negative decimal integers, representing time
+        in seconds.""",
+    )
+    content_type = header_property(
+        "Content-Type",
+        doc="""The Content-Type entity-header field indicates the media
+        type of the entity-body sent to the recipient or, in the case of
+        the HEAD method, the media type that would have been sent had
+        the request been a GET.""",
+    )
+    content_length = header_property(
+        "Content-Length",
+        None,
+        int,
+        str,
+        doc="""The Content-Length entity-header field indicates the size
+        of the entity-body, in decimal number of OCTETs, sent to the
+        recipient or, in the case of the HEAD method, the size of the
+        entity-body that would have been sent had the request been a
+        GET.""",
+    )
+    content_location = header_property(
+        "Content-Location",
+        doc="""The Content-Location entity-header field MAY be used to
+        supply the resource location for the entity enclosed in the
+        message when that entity is accessible from a location separate
+        from the requested resource's URI.""",
+    )
+    content_encoding = header_property(
+        "Content-Encoding",
+        doc="""The Content-Encoding entity-header field is used as a
+        modifier to the media-type. When present, its value indicates
+        what additional content codings have been applied to the
+        entity-body, and thus what decoding mechanisms must be applied
+        in order to obtain the media-type referenced by the Content-Type
+        header field.""",
+    )
+    content_md5 = header_property(
+        "Content-MD5",
+        doc="""The Content-MD5 entity-header field, as defined in
+        RFC 1864, is an MD5 digest of the entity-body for the purpose of
+        providing an end-to-end message integrity check (MIC) of the
+        entity-body. (Note: a MIC is good for detecting accidental
+        modification of the entity-body in transit, but is not proof
+        against malicious attacks.)""",
+    )
+    date = header_property(
+        "Date",
+        None,
+        parse_date,
+        http_date,
+        doc="""The Date general-header field represents the date and
+        time at which the message was originated, having the same
+        semantics as orig-date in RFC 822.""",
+    )
+    expires = header_property(
+        "Expires",
+        None,
+        parse_date,
+        http_date,
+        doc="""The Expires entity-header field gives the date/time after
+        which the response is considered stale. A stale cache entry may
+        not normally be returned by a cache.""",
+    )
+    last_modified = header_property(
+        "Last-Modified",
+        None,
+        parse_date,
+        http_date,
+        doc="""The Last-Modified entity-header field indicates the date
+        and time at which the origin server believes the variant was
+        last modified.""",
+    )
+
+    @property
+    def retry_after(self):
+        """The Retry-After response-header field can be used with a
+        503 (Service Unavailable) response to indicate how long the
+        service is expected to be unavailable to the requesting client.
+
+        Time in seconds until expiration or date.
+        """
+        value = self.headers.get("retry-after")
+        if value is None:
+            return
+        elif value.isdigit():
+            return datetime.utcnow() + timedelta(seconds=int(value))
+        return parse_date(value)
+
+    @retry_after.setter
+    def retry_after(self, value):
+        if value is None:
+            if "retry-after" in self.headers:
+                del self.headers["retry-after"]
+            return
+        elif isinstance(value, datetime):
+            value = http_date(value)
+        else:
+            value = str(value)
+        self.headers["Retry-After"] = value
+
+    def _set_property(name, doc=None):  # noqa: B902
+        def fget(self):
+            def on_update(header_set):
+                if not header_set and name in self.headers:
+                    del self.headers[name]
+                elif header_set:
+                    self.headers[name] = header_set.to_header()
+
+            return parse_set_header(self.headers.get(name), on_update)
+
+        def fset(self, value):
+            if not value:
+                del self.headers[name]
+            elif isinstance(value, string_types):
+                self.headers[name] = value
+            else:
+                self.headers[name] = dump_header(value)
+
+        return property(fget, fset, doc=doc)
+
+    vary = _set_property(
+        "Vary",
+        doc="""The Vary field value indicates the set of request-header
+        fields that fully determines, while the response is fresh,
+        whether a cache is permitted to use the response to reply to a
+        subsequent request without revalidation.""",
+    )
+    content_language = _set_property(
+        "Content-Language",
+        doc="""The Content-Language entity-header field describes the
+        natural language(s) of the intended audience for the enclosed
+        entity. Note that this might not be equivalent to all the
+        languages used within the entity-body.""",
+    )
+    allow = _set_property(
+        "Allow",
+        doc="""The Allow entity-header field lists the set of methods
+        supported by the resource identified by the Request-URI. The
+        purpose of this field is strictly to inform the recipient of
+        valid methods associated with the resource. An Allow header
+        field MUST be present in a 405 (Method Not Allowed)
+        response.""",
+    )
+
+    del _set_property
diff --git a/python/werkzeug/wrappers/etag.py b/python/werkzeug/wrappers/etag.py
new file mode 100644
index 0000000..0733506
--- /dev/null
+++ b/python/werkzeug/wrappers/etag.py
@@ -0,0 +1,304 @@
+from .._compat import string_types
+from .._internal import _get_environ
+from ..datastructures import ContentRange
+from ..datastructures import RequestCacheControl
+from ..datastructures import ResponseCacheControl
+from ..http import generate_etag
+from ..http import http_date
+from ..http import is_resource_modified
+from ..http import parse_cache_control_header
+from ..http import parse_content_range_header
+from ..http import parse_date
+from ..http import parse_etags
+from ..http import parse_if_range_header
+from ..http import parse_range_header
+from ..http import quote_etag
+from ..http import unquote_etag
+from ..utils import cached_property
+from ..utils import header_property
+from ..wrappers.base_response import _clean_accept_ranges
+from ..wsgi import _RangeWrapper
+
+
+class ETagRequestMixin(object):
+    """Add entity tag and cache descriptors to a request object or object with
+    a WSGI environment available as :attr:`~BaseRequest.environ`.  This not
+    only provides access to etags but also to the cache control header.
+    """
+
+    @cached_property
+    def cache_control(self):
+        """A :class:`~werkzeug.datastructures.RequestCacheControl` object
+        for the incoming cache control headers.
+        """
+        cache_control = self.environ.get("HTTP_CACHE_CONTROL")
+        return parse_cache_control_header(cache_control, None, RequestCacheControl)
+
+    @cached_property
+    def if_match(self):
+        """An object containing all the etags in the `If-Match` header.
+
+        :rtype: :class:`~werkzeug.datastructures.ETags`
+        """
+        return parse_etags(self.environ.get("HTTP_IF_MATCH"))
+
+    @cached_property
+    def if_none_match(self):
+        """An object containing all the etags in the `If-None-Match` header.
+
+        :rtype: :class:`~werkzeug.datastructures.ETags`
+        """
+        return parse_etags(self.environ.get("HTTP_IF_NONE_MATCH"))
+
+    @cached_property
+    def if_modified_since(self):
+        """The parsed `If-Modified-Since` header as datetime object."""
+        return parse_date(self.environ.get("HTTP_IF_MODIFIED_SINCE"))
+
+    @cached_property
+    def if_unmodified_since(self):
+        """The parsed `If-Unmodified-Since` header as datetime object."""
+        return parse_date(self.environ.get("HTTP_IF_UNMODIFIED_SINCE"))
+
+    @cached_property
+    def if_range(self):
+        """The parsed `If-Range` header.
+
+        .. versionadded:: 0.7
+
+        :rtype: :class:`~werkzeug.datastructures.IfRange`
+        """
+        return parse_if_range_header(self.environ.get("HTTP_IF_RANGE"))
+
+    @cached_property
+    def range(self):
+        """The parsed `Range` header.
+
+        .. versionadded:: 0.7
+
+        :rtype: :class:`~werkzeug.datastructures.Range`
+        """
+        return parse_range_header(self.environ.get("HTTP_RANGE"))
+
+
+class ETagResponseMixin(object):
+    """Adds extra functionality to a response object for etag and cache
+    handling.  This mixin requires an object with at least a `headers`
+    object that implements a dict like interface similar to
+    :class:`~werkzeug.datastructures.Headers`.
+
+    If you want the :meth:`freeze` method to automatically add an etag, you
+    have to mixin this method before the response base class.  The default
+    response class does not do that.
+    """
+
+    @property
+    def cache_control(self):
+        """The Cache-Control general-header field is used to specify
+        directives that MUST be obeyed by all caching mechanisms along the
+        request/response chain.
+        """
+
+        def on_update(cache_control):
+            if not cache_control and "cache-control" in self.headers:
+                del self.headers["cache-control"]
+            elif cache_control:
+                self.headers["Cache-Control"] = cache_control.to_header()
+
+        return parse_cache_control_header(
+            self.headers.get("cache-control"), on_update, ResponseCacheControl
+        )
+
+    def _wrap_response(self, start, length):
+        """Wrap existing Response in case of Range Request context."""
+        if self.status_code == 206:
+            self.response = _RangeWrapper(self.response, start, length)
+
+    def _is_range_request_processable(self, environ):
+        """Return ``True`` if `Range` header is present and if underlying
+        resource is considered unchanged when compared with `If-Range` header.
+        """
+        return (
+            "HTTP_IF_RANGE" not in environ
+            or not is_resource_modified(
+                environ,
+                self.headers.get("etag"),
+                None,
+                self.headers.get("last-modified"),
+                ignore_if_range=False,
+            )
+        ) and "HTTP_RANGE" in environ
+
+    def _process_range_request(self, environ, complete_length=None, accept_ranges=None):
+        """Handle Range Request related headers (RFC7233).  If `Accept-Ranges`
+        header is valid, and Range Request is processable, we set the headers
+        as described by the RFC, and wrap the underlying response in a
+        RangeWrapper.
+
+        Returns ``True`` if Range Request can be fulfilled, ``False`` otherwise.
+
+        :raises: :class:`~werkzeug.exceptions.RequestedRangeNotSatisfiable`
+                 if `Range` header could not be parsed or satisfied.
+        """
+        from ..exceptions import RequestedRangeNotSatisfiable
+
+        if accept_ranges is None:
+            return False
+        self.headers["Accept-Ranges"] = accept_ranges
+        if not self._is_range_request_processable(environ) or complete_length is None:
+            return False
+        parsed_range = parse_range_header(environ.get("HTTP_RANGE"))
+        if parsed_range is None:
+            raise RequestedRangeNotSatisfiable(complete_length)
+        range_tuple = parsed_range.range_for_length(complete_length)
+        content_range_header = parsed_range.to_content_range_header(complete_length)
+        if range_tuple is None or content_range_header is None:
+            raise RequestedRangeNotSatisfiable(complete_length)
+        content_length = range_tuple[1] - range_tuple[0]
+        # Be sure not to send 206 response
+        # if requested range is the full content.
+        if content_length != complete_length:
+            self.headers["Content-Length"] = content_length
+            self.content_range = content_range_header
+            self.status_code = 206
+            self._wrap_response(range_tuple[0], content_length)
+            return True
+        return False
+
+    def make_conditional(
+        self, request_or_environ, accept_ranges=False, complete_length=None
+    ):
+        """Make the response conditional to the request.  This method works
+        best if an etag was defined for the response already.  The `add_etag`
+        method can be used to do that.  If called without etag just the date
+        header is set.
+
+        This does nothing if the request method in the request or environ is
+        anything but GET or HEAD.
+
+        For optimal performance when handling range requests, it's recommended
+        that your response data object implements `seekable`, `seek` and `tell`
+        methods as described by :py:class:`io.IOBase`.  Objects returned by
+        :meth:`~werkzeug.wsgi.wrap_file` automatically implement those methods.
+
+        It does not remove the body of the response because that's something
+        the :meth:`__call__` function does for us automatically.
+
+        Returns self so that you can do ``return resp.make_conditional(req)``
+        but modifies the object in-place.
+
+        :param request_or_environ: a request object or WSGI environment to be
+                                   used to make the response conditional
+                                   against.
+        :param accept_ranges: This parameter dictates the value of
+                              `Accept-Ranges` header. If ``False`` (default),
+                              the header is not set. If ``True``, it will be set
+                              to ``"bytes"``. If ``None``, it will be set to
+                              ``"none"``. If it's a string, it will use this
+                              value.
+        :param complete_length: Will be used only in valid Range Requests.
+                                It will set `Content-Range` complete length
+                                value and compute `Content-Length` real value.
+                                This parameter is mandatory for successful
+                                Range Requests completion.
+        :raises: :class:`~werkzeug.exceptions.RequestedRangeNotSatisfiable`
+                 if `Range` header could not be parsed or satisfied.
+        """
+        environ = _get_environ(request_or_environ)
+        if environ["REQUEST_METHOD"] in ("GET", "HEAD"):
+            # if the date is not in the headers, add it now.  We however
+            # will not override an already existing header.  Unfortunately
+            # this header will be overriden by many WSGI servers including
+            # wsgiref.
+            if "date" not in self.headers:
+                self.headers["Date"] = http_date()
+            accept_ranges = _clean_accept_ranges(accept_ranges)
+            is206 = self._process_range_request(environ, complete_length, accept_ranges)
+            if not is206 and not is_resource_modified(
+                environ,
+                self.headers.get("etag"),
+                None,
+                self.headers.get("last-modified"),
+            ):
+                if parse_etags(environ.get("HTTP_IF_MATCH")):
+                    self.status_code = 412
+                else:
+                    self.status_code = 304
+            if (
+                self.automatically_set_content_length
+                and "content-length" not in self.headers
+            ):
+                length = self.calculate_content_length()
+                if length is not None:
+                    self.headers["Content-Length"] = length
+        return self
+
+    def add_etag(self, overwrite=False, weak=False):
+        """Add an etag for the current response if there is none yet."""
+        if overwrite or "etag" not in self.headers:
+            self.set_etag(generate_etag(self.get_data()), weak)
+
+    def set_etag(self, etag, weak=False):
+        """Set the etag, and override the old one if there was one."""
+        self.headers["ETag"] = quote_etag(etag, weak)
+
+    def get_etag(self):
+        """Return a tuple in the form ``(etag, is_weak)``.  If there is no
+        ETag the return value is ``(None, None)``.
+        """
+        return unquote_etag(self.headers.get("ETag"))
+
+    def freeze(self, no_etag=False):
+        """Call this method if you want to make your response object ready for
+        pickeling.  This buffers the generator if there is one.  This also
+        sets the etag unless `no_etag` is set to `True`.
+        """
+        if not no_etag:
+            self.add_etag()
+        super(ETagResponseMixin, self).freeze()
+
+    accept_ranges = header_property(
+        "Accept-Ranges",
+        doc="""The `Accept-Ranges` header. Even though the name would
+        indicate that multiple values are supported, it must be one
+        string token only.
+
+        The values ``'bytes'`` and ``'none'`` are common.
+
+        .. versionadded:: 0.7""",
+    )
+
+    def _get_content_range(self):
+        def on_update(rng):
+            if not rng:
+                del self.headers["content-range"]
+            else:
+                self.headers["Content-Range"] = rng.to_header()
+
+        rv = parse_content_range_header(self.headers.get("content-range"), on_update)
+        # always provide a content range object to make the descriptor
+        # more user friendly.  It provides an unset() method that can be
+        # used to remove the header quickly.
+        if rv is None:
+            rv = ContentRange(None, None, None, on_update=on_update)
+        return rv
+
+    def _set_content_range(self, value):
+        if not value:
+            del self.headers["content-range"]
+        elif isinstance(value, string_types):
+            self.headers["Content-Range"] = value
+        else:
+            self.headers["Content-Range"] = value.to_header()
+
+    content_range = property(
+        _get_content_range,
+        _set_content_range,
+        doc="""The ``Content-Range`` header as
+        :class:`~werkzeug.datastructures.ContentRange` object. Even if
+        the header is not set it wil provide such an object for easier
+        manipulation.
+
+        .. versionadded:: 0.7""",
+    )
+    del _get_content_range, _set_content_range
diff --git a/python/werkzeug/wrappers/json.py b/python/werkzeug/wrappers/json.py
new file mode 100644
index 0000000..6d5dc33
--- /dev/null
+++ b/python/werkzeug/wrappers/json.py
@@ -0,0 +1,145 @@
+from __future__ import absolute_import
+
+import datetime
+import uuid
+
+from .._compat import text_type
+from ..exceptions import BadRequest
+from ..utils import detect_utf_encoding
+
+try:
+    import simplejson as _json
+except ImportError:
+    import json as _json
+
+
+class _JSONModule(object):
+    @staticmethod
+    def _default(o):
+        if isinstance(o, datetime.date):
+            return o.isoformat()
+
+        if isinstance(o, uuid.UUID):
+            return str(o)
+
+        if hasattr(o, "__html__"):
+            return text_type(o.__html__())
+
+        raise TypeError()
+
+    @classmethod
+    def dumps(cls, obj, **kw):
+        kw.setdefault("separators", (",", ":"))
+        kw.setdefault("default", cls._default)
+        kw.setdefault("sort_keys", True)
+        return _json.dumps(obj, **kw)
+
+    @staticmethod
+    def loads(s, **kw):
+        if isinstance(s, bytes):
+            # Needed for Python < 3.6
+            encoding = detect_utf_encoding(s)
+            s = s.decode(encoding)
+
+        return _json.loads(s, **kw)
+
+
+class JSONMixin(object):
+    """Mixin to parse :attr:`data` as JSON. Can be mixed in for both
+    :class:`~werkzeug.wrappers.Request` and
+    :class:`~werkzeug.wrappers.Response` classes.
+
+    If `simplejson`_ is installed it is preferred over Python's built-in
+    :mod:`json` module.
+
+    .. _simplejson: https://simplejson.readthedocs.io/en/latest/
+    """
+
+    #: A module or other object that has ``dumps`` and ``loads``
+    #: functions that match the API of the built-in :mod:`json` module.
+    json_module = _JSONModule
+
+    @property
+    def json(self):
+        """The parsed JSON data if :attr:`mimetype` indicates JSON
+        (:mimetype:`application/json`, see :meth:`is_json`).
+
+        Calls :meth:`get_json` with default arguments.
+        """
+        return self.get_json()
+
+    @property
+    def is_json(self):
+        """Check if the mimetype indicates JSON data, either
+        :mimetype:`application/json` or :mimetype:`application/*+json`.
+        """
+        mt = self.mimetype
+        return (
+            mt == "application/json"
+            or mt.startswith("application/")
+            and mt.endswith("+json")
+        )
+
+    def _get_data_for_json(self, cache):
+        try:
+            return self.get_data(cache=cache)
+        except TypeError:
+            # Response doesn't have cache param.
+            return self.get_data()
+
+    # Cached values for ``(silent=False, silent=True)``. Initialized
+    # with sentinel values.
+    _cached_json = (Ellipsis, Ellipsis)
+
+    def get_json(self, force=False, silent=False, cache=True):
+        """Parse :attr:`data` as JSON.
+
+        If the mimetype does not indicate JSON
+        (:mimetype:`application/json`, see :meth:`is_json`), this
+        returns ``None``.
+
+        If parsing fails, :meth:`on_json_loading_failed` is called and
+        its return value is used as the return value.
+
+        :param force: Ignore the mimetype and always try to parse JSON.
+        :param silent: Silence parsing errors and return ``None``
+            instead.
+        :param cache: Store the parsed JSON to return for subsequent
+            calls.
+        """
+        if cache and self._cached_json[silent] is not Ellipsis:
+            return self._cached_json[silent]
+
+        if not (force or self.is_json):
+            return None
+
+        data = self._get_data_for_json(cache=cache)
+
+        try:
+            rv = self.json_module.loads(data)
+        except ValueError as e:
+            if silent:
+                rv = None
+
+                if cache:
+                    normal_rv, _ = self._cached_json
+                    self._cached_json = (normal_rv, rv)
+            else:
+                rv = self.on_json_loading_failed(e)
+
+                if cache:
+                    _, silent_rv = self._cached_json
+                    self._cached_json = (rv, silent_rv)
+        else:
+            if cache:
+                self._cached_json = (rv, rv)
+
+        return rv
+
+    def on_json_loading_failed(self, e):
+        """Called if :meth:`get_json` parsing fails and isn't silenced.
+        If this method returns a value, it is used as the return value
+        for :meth:`get_json`. The default implementation raises
+        :exc:`~werkzeug.exceptions.BadRequest`.
+        """
+        raise BadRequest("Failed to decode JSON object: {0}".format(e))
diff --git a/python/werkzeug/wrappers/request.py b/python/werkzeug/wrappers/request.py
new file mode 100644
index 0000000..d1c71b6
--- /dev/null
+++ b/python/werkzeug/wrappers/request.py
@@ -0,0 +1,44 @@
+from .accept import AcceptMixin
+from .auth import AuthorizationMixin
+from .base_request import BaseRequest
+from .common_descriptors import CommonRequestDescriptorsMixin
+from .etag import ETagRequestMixin
+from .user_agent import UserAgentMixin
+
+
+class Request(
+    BaseRequest,
+    AcceptMixin,
+    ETagRequestMixin,
+    UserAgentMixin,
+    AuthorizationMixin,
+    CommonRequestDescriptorsMixin,
+):
+    """Full featured request object implementing the following mixins:
+
+    - :class:`AcceptMixin` for accept header parsing
+    - :class:`ETagRequestMixin` for etag and cache control handling
+    - :class:`UserAgentMixin` for user agent introspection
+    - :class:`AuthorizationMixin` for http auth handling
+    - :class:`CommonRequestDescriptorsMixin` for common headers
+    """
+
+
+class StreamOnlyMixin(object):
+    """If mixed in before the request object this will change the bahavior
+    of it to disable handling of form parsing.  This disables the
+    :attr:`files`, :attr:`form` attributes and will just provide a
+    :attr:`stream` attribute that however is always available.
+
+    .. versionadded:: 0.9
+    """
+
+    disable_data_descriptor = True
+    want_form_data_parsed = False
+
+
+class PlainRequest(StreamOnlyMixin, Request):
+    """A request object without special form parsing capabilities.
+
+    .. versionadded:: 0.9
+    """
diff --git a/python/werkzeug/wrappers/response.py b/python/werkzeug/wrappers/response.py
new file mode 100644
index 0000000..cd86cac
--- /dev/null
+++ b/python/werkzeug/wrappers/response.py
@@ -0,0 +1,78 @@
+from ..utils import cached_property
+from .auth import WWWAuthenticateMixin
+from .base_response import BaseResponse
+from .common_descriptors import CommonResponseDescriptorsMixin
+from .etag import ETagResponseMixin
+
+
+class ResponseStream(object):
+    """A file descriptor like object used by the :class:`ResponseStreamMixin` to
+    represent the body of the stream.  It directly pushes into the response
+    iterable of the response object.
+    """
+
+    mode = "wb+"
+
+    def __init__(self, response):
+        self.response = response
+        self.closed = False
+
+    def write(self, value):
+        if self.closed:
+            raise ValueError("I/O operation on closed file")
+        self.response._ensure_sequence(mutable=True)
+        self.response.response.append(value)
+        self.response.headers.pop("Content-Length", None)
+        return len(value)
+
+    def writelines(self, seq):
+        for item in seq:
+            self.write(item)
+
+    def close(self):
+        self.closed = True
+
+    def flush(self):
+        if self.closed:
+            raise ValueError("I/O operation on closed file")
+
+    def isatty(self):
+        if self.closed:
+            raise ValueError("I/O operation on closed file")
+        return False
+
+    def tell(self):
+        self.response._ensure_sequence()
+        return sum(map(len, self.response.response))
+
+    @property
+    def encoding(self):
+        return self.response.charset
+
+
+class ResponseStreamMixin(object):
+    """Mixin for :class:`BaseRequest` subclasses.  Classes that inherit from
+    this mixin will automatically get a :attr:`stream` property that provides
+    a write-only interface to the response iterable.
+    """
+
+    @cached_property
+    def stream(self):
+        """The response iterable as write-only stream."""
+        return ResponseStream(self)
+
+
+class Response(
+    BaseResponse,
+    ETagResponseMixin,
+    ResponseStreamMixin,
+    CommonResponseDescriptorsMixin,
+    WWWAuthenticateMixin,
+):
+    """Full featured response object implementing the following mixins:
+
+    - :class:`ETagResponseMixin` for etag and cache control handling
+    - :class:`ResponseStreamMixin` to add support for the `stream` property
+    - :class:`CommonResponseDescriptorsMixin` for various HTTP descriptors
+    - :class:`WWWAuthenticateMixin` for HTTP authentication support
+    """
diff --git a/python/werkzeug/wrappers/user_agent.py b/python/werkzeug/wrappers/user_agent.py
new file mode 100644
index 0000000..72588dd
--- /dev/null
+++ b/python/werkzeug/wrappers/user_agent.py
@@ -0,0 +1,15 @@
+from ..utils import cached_property
+
+
+class UserAgentMixin(object):
+    """Adds a `user_agent` attribute to the request object which
+    contains the parsed user agent of the browser that triggered the
+    request as a :class:`~werkzeug.useragents.UserAgent` object.
+    """
+
+    @cached_property
+    def user_agent(self):
+        """The current user agent."""
+        from ..useragents import UserAgent
+
+        return UserAgent(self.environ)