# -*- coding: utf-8 -*- """ 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: (c) 2011 by the Werkzeug Team, see AUTHORS for more details. :license: BSD, see LICENSE for more details. """ import urlparse from datetime import datetime, timedelta from werkzeug.http import HTTP_STATUS_CODES, \ parse_accept_header, parse_cache_control_header, parse_etags, \ parse_date, generate_etag, is_resource_modified, unquote_etag, \ quote_etag, parse_set_header, parse_authorization_header, \ parse_www_authenticate_header, remove_entity_headers, \ parse_options_header, dump_options_header, http_date, \ parse_if_range_header, parse_cookie, dump_cookie, \ parse_range_header, parse_content_range_header, dump_header from werkzeug.urls import url_decode, iri_to_uri from werkzeug.formparser import FormDataParser, default_stream_factory from werkzeug.utils import cached_property, environ_property, \ header_property, get_content_type from werkzeug.wsgi import get_current_url, get_host, LimitedStream, \ ClosingIterator from werkzeug.datastructures import MultiDict, CombinedMultiDict, Headers, \ EnvironHeaders, ImmutableMultiDict, ImmutableTypeConversionDict, \ ImmutableList, MIMEAccept, CharsetAccept, LanguageAccept, \ ResponseCacheControl, RequestCacheControl, CallbackDict, \ ContentRange from werkzeug._internal import _empty_stream, _decode_unicode, \ _patch_wrapper, _get_environ 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 werkzeug.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, basestring): from warnings import warn warn(Warning('response iterable was set to a string. This appears ' 'to work but means that the server will send the ' 'data to the client char, by char. This is almost ' 'never intended behavior, use response.data to assign ' 'strings to the response object.'), stacklevel=2) 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 `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 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'" % self.url) 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 werkzeug.test import EnvironBuilder charset = kwargs.pop('charset', cls.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:: @Request.application def my_wsgi_app(request): return Response('Hello World!') :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. return _patch_wrapper(f, lambda *a: f(*a[:-2]+(cls(a[-2]),))(*a[-2:])) 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, content_type, filename, content_length) @property def want_form_data_parsed(self): """Returns True if the request method is ``POST``, ``PUT`` or ``PATCH``. Can be overriden to support other HTTP methods that should carry form data. .. versionadded:: 0.8 """ return self.environ['REQUEST_METHOD'] in ('POST', 'PUT', 'PATCH') def make_form_data_parser(self): """Creates the form data parser. Instanciates 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. .. versionadded:: 0.8 """ # abort early if we have already consumed the stream if 'stream' in self.__dict__: return if self.shallow: raise RuntimeError('A shallow request tried to consume ' 'form data. If you really want to do ' 'that, set `shallow` to False.') data = None stream = _empty_stream if self.want_form_data_parsed: parser = self.make_form_data_parser() data = parser.parse_from_environ(self.environ) else: # if we have a content length header we are able to properly # guard the incoming stream, no matter what request method is # used. content_length = self.headers.get('content-length', type=int) if content_length is not None: stream = LimitedStream(self.environ['wsgi.input'], content_length) if data is None: data = (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 @cached_property def stream(self): """The parsed stream if the submitted data was not multipart or urlencoded form data. This stream is the stream left by the form data parser module after parsing. This is *not* the WSGI input stream but a wrapper around it that ensures the caller does not accidentally read past `Content-Length`. """ self._load_form_data() return self.stream input_stream = environ_property('wsgi.input', 'The WSGI input stream.\n' '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. 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(self.environ.get('QUERY_STRING', ''), self.url_charset, errors=self.encoding_errors, cls=self.parameter_storage_class) @cached_property def data(self): """This reads the buffered incoming data from the client into the string. Usually it's a bad idea to access :attr:`data` because a client could send dozens of megabytes or more to cause memory problems on the server. To circumvent that make sure to check the content length first. """ return self.stream.read() @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. """ self._load_form_data() return self.form @cached_property def values(self): """Combined multi dict for :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. Note that :attr:`files` will only contain data if the request method was POST, PUT or PATCH and the ``
`` 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): """Read only access to the retrieved cookie values as dictionary.""" return parse_cookie(self.environ, self.charset, 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. """ path = '/' + (self.environ.get('PATH_INFO') or '').lstrip('/') return _decode_unicode(path, self.url_charset, self.encoding_errors) @cached_property def script_root(self): """The root path of the script without the trailing slash.""" path = (self.environ.get('SCRIPT_NAME') or '').rstrip('/') return _decode_unicode(path, self.url_charset, self.encoding_errors) @cached_property def url(self): """The reconstructed current URL""" return get_current_url(self.environ) @cached_property def base_url(self): """Like :attr:`url` but without the querystring""" return get_current_url(self.environ, strip_querystring=True) @cached_property def url_root(self): """The full URL root (with hostname), this is the application root.""" return get_current_url(self.environ, True) @cached_property def host_url(self): """Just the host with scheme.""" return get_current_url(self.environ, host_only=True) @cached_property def host(self): """Just the host including the port if available.""" return get_host(self.environ) query_string = environ_property('QUERY_STRING', '', read_only=True, doc= '''The URL parameters as raw bytestring.''') method = environ_property('REQUEST_METHOD', 'GET', read_only=True, doc= '''The transmission 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''') is_xhr = property(lambda x: x.environ.get('HTTP_X_REQUESTED_WITH', '') .lower() == 'xmlhttprequest', doc=''' 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.''') is_secure = property(lambda x: x.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 exeuction only happens one time.''') 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 know interface. Per default the request object will assume all the text data is `utf-8` encoded. Please refer to `the unicode chapter `_ 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/` it becomes a charset parameter defined with the charset of the response object. 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 request. See notice above. :param content_type: the content type for the request. 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 though 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 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, (int, long)): 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, basestring): self.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 = self.is_streamed and 'streamed' or '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, '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): self._status = value try: self._status_code = int(self._status.split(None, 1)[0]) except ValueError: self._status_code = 0 status = property(_get_status, _set_status, 'The HTTP Status code') del _get_status, _set_status def _get_data(self): """The string representation of the request body. Whenever you access 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`. """ self._ensure_sequence() return ''.join(self.iter_encoded()) def _set_data(self, value): # if an unicode string is set, it's encoded directly so that we # can set the content length if isinstance(value, unicode): value = value.encode(self.charset) self.response = [value] if self.automatically_set_content_length: self.headers['Content-Length'] = str(len(value)) data = property(_get_data, _set_data, doc=_get_data.__doc__) del _get_data, _set_data 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 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, charset=None): """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. .. versionchanged:: 0.6 The `charset` parameter was deprecated and became a no-op. """ # XXX: deprecated if __debug__ and charset is not None: # pragma: no cover from warnings import warn warn(DeprecationWarning('charset was deprecated and is ignored.'), stacklevel=2) charset = self.charset if __debug__: _warn_if_string(self.response) for item in self.response: if isinstance(item, unicode): yield item.encode(charset) else: yield str(item) def set_cookie(self, key, value='', max_age=None, expires=None, path='/', domain=None, secure=None, httponly=False): """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. :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 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 path: limits the cookie to a given path, per default it will span the whole domain. """ self.headers.add('Set-Cookie', dump_cookie(key, value, max_age, expires, path, domain, secure, httponly, self.charset)) 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 header_list(self): # pragma: no cover # XXX: deprecated if __debug__: from warnings import warn warn(DeprecationWarning('header_list is deprecated'), stacklevel=2) return self.headers.to_list(self.charset) @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: 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.""" if hasattr(self.response, 'close'): self.response.close() for func in self._on_close: func() 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 fix_headers(self, environ): # XXX: deprecated if __debug__: from warnings import warn warn(DeprecationWarning('called into deprecated fix_headers baseclass ' 'method. Use get_wsgi_headers instead.'), stacklevel=2) self.headers[:] = self.get_wsgi_headers(environ) 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 == 'location': location = value elif ikey == 'content-location': content_location = value elif ikey == '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, unicode): location = iri_to_uri(location) if self.autocorrect_location_header: location = urlparse.urljoin( get_current_url(environ, root_only=True), 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, unicode): headers['Content-Location'] = iri_to_uri(content_location) # remove entity headers and set content length to zero if needed. # Also update content_length accordingly so that the automatic # content length detection does not trigger in the following # code. if 100 <= status < 200 or status == 204: headers['Content-Length'] = content_length = '0' 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 != 304: try: content_length = sum(len(str(x)) 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): return () if self.direct_passthrough: if __debug__: _warn_if_string(self.response) return self.response return ClosingIterator(self.iter_encoded(), 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. """ # XXX: code for backwards compatibility with custom fix_headers # methods. if self.fix_headers.func_code is not \ BaseResponse.fix_headers.func_code: if __debug__: from warnings import warn warn(DeprecationWarning('fix_headers changed behavior in 0.6 ' 'and is now called get_wsgi_headers. ' 'See documentation for more details.'), stacklevel=2) self.fix_headers(environ) headers = self.headers else: headers = self.get_wsgi_headers(environ) app_iter = self.get_app_iter(environ) return app_iter, self.status, headers.to_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 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) 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 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 werkzeug.useragents import UserAgent return UserAgent(self.environ) 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 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 make_conditional(self, request_or_environ): """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. 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. """ 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() if 'content-length' not in self.headers: self.headers['Content-Length'] = len(self.data) if not is_resource_modified(environ, self.headers.get('etag'), None, self.headers.get('last-modified')): self.status_code = 304 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.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, basestring): 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 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) 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 @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 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.''') content_length = environ_property('CONTENT_LENGTH', None, int, str, doc=''' 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.''') 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.). 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] @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. """ def _get_mimetype(self): ct = self.headers.get('content-type') if ct: return ct.split(';')[0].strip() def _set_mimetype(self, value): self.headers['Content-Type'] = get_content_type(value, self.charset) def _get_mimetype_params(self): 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) mimetype = property(_get_mimetype, _set_mimetype, doc=''' The mimetype (content type without charset etc.)''') mimetype_params = property(_get_mimetype_params, doc=''' 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 ''') 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_date, http_date, 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.''') def _get_retry_after(self): 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) def _set_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 retry_after = property(_get_retry_after, _set_retry_after, doc=''' 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.''') def _set_property(name, doc=None): 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, basestring): 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, _get_mimetype, _set_mimetype, _get_retry_after, \ _set_retry_after 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) 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 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 """