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 ` 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 ````. 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 ``