django1/django/http/response.py

442 lines
16 KiB
Python

from __future__ import absolute_import, unicode_literals
import datetime
import time
import warnings
from email.header import Header
try:
from urllib.parse import urlparse
except ImportError:
from urlparse import urlparse
from django.conf import settings
from django.core import signing
from django.core.exceptions import SuspiciousOperation
from django.http.cookie import SimpleCookie
from django.utils import six, timezone
from django.utils.encoding import force_bytes, iri_to_uri
from django.utils.http import cookie_date
from django.utils.six.moves import map
class BadHeaderError(ValueError):
pass
class HttpResponseBase(object):
"""
An HTTP response base class with dictionary-accessed headers.
This class doesn't handle content. It should not be used directly.
Use the HttpResponse and StreamingHttpResponse subclasses instead.
"""
status_code = 200
def __init__(self, content_type=None, status=None, mimetype=None):
# _headers is a mapping of the lower-case name to the original case of
# the header (required for working with legacy systems) and the header
# value. Both the name of the header and its value are ASCII strings.
self._headers = {}
self._charset = settings.DEFAULT_CHARSET
self._closable_objects = []
if mimetype:
warnings.warn("Using mimetype keyword argument is deprecated, use"
" content_type instead", PendingDeprecationWarning)
content_type = mimetype
if not content_type:
content_type = "%s; charset=%s" % (settings.DEFAULT_CONTENT_TYPE,
self._charset)
self.cookies = SimpleCookie()
if status:
self.status_code = status
self['Content-Type'] = content_type
def serialize_headers(self):
"""HTTP headers as a bytestring."""
headers = [
('%s: %s' % (key, value)).encode('us-ascii')
for key, value in self._headers.values()
]
return b'\r\n'.join(headers)
if six.PY3:
__bytes__ = serialize_headers
else:
__str__ = serialize_headers
def _convert_to_charset(self, value, charset, mime_encode=False):
"""Converts headers key/value to ascii/latin1 native strings.
`charset` must be 'ascii' or 'latin-1'. If `mime_encode` is True and
`value` value can't be represented in the given charset, MIME-encoding
is applied.
"""
if not isinstance(value, (bytes, six.text_type)):
value = str(value)
try:
if six.PY3:
if isinstance(value, str):
# Ensure string is valid in given charset
value.encode(charset)
else:
# Convert bytestring using given charset
value = value.decode(charset)
else:
if isinstance(value, str):
# Ensure string is valid in given charset
value.decode(charset)
else:
# Convert unicode string to given charset
value = value.encode(charset)
except UnicodeError as e:
if mime_encode:
# Wrapping in str() is a workaround for #12422 under Python 2.
value = str(Header(value, 'utf-8').encode())
else:
e.reason += ', HTTP response headers must be in %s format' % charset
raise
if str('\n') in value or str('\r') in value:
raise BadHeaderError("Header values can't contain newlines (got %r)" % value)
return value
def __setitem__(self, header, value):
header = self._convert_to_charset(header, 'ascii')
value = self._convert_to_charset(value, 'latin1', mime_encode=True)
self._headers[header.lower()] = (header, value)
def __delitem__(self, header):
try:
del self._headers[header.lower()]
except KeyError:
pass
def __getitem__(self, header):
return self._headers[header.lower()][1]
def __getstate__(self):
# SimpleCookie is not pickeable with pickle.HIGHEST_PROTOCOL, so we
# serialise to a string instead
state = self.__dict__.copy()
state['cookies'] = str(state['cookies'])
return state
def __setstate__(self, state):
self.__dict__.update(state)
self.cookies = SimpleCookie(self.cookies)
def has_header(self, header):
"""Case-insensitive check for a header."""
return header.lower() in self._headers
__contains__ = has_header
def items(self):
return self._headers.values()
def get(self, header, alternate=None):
return self._headers.get(header.lower(), (None, alternate))[1]
def set_cookie(self, key, value='', max_age=None, expires=None, path='/',
domain=None, secure=False, httponly=False):
"""
Sets a cookie.
``expires`` can be:
- a string in the correct format,
- a naive ``datetime.datetime`` object in UTC,
- an aware ``datetime.datetime`` object in any time zone.
If it is a ``datetime.datetime`` object then ``max_age`` will be calculated.
"""
self.cookies[key] = value
if expires is not None:
if isinstance(expires, datetime.datetime):
if timezone.is_aware(expires):
expires = timezone.make_naive(expires, timezone.utc)
delta = expires - expires.utcnow()
# Add one second so the date matches exactly (a fraction of
# time gets lost between converting to a timedelta and
# then the date string).
delta = delta + datetime.timedelta(seconds=1)
# Just set max_age - the max_age logic will set expires.
expires = None
max_age = max(0, delta.days * 86400 + delta.seconds)
else:
self.cookies[key]['expires'] = expires
if max_age is not None:
self.cookies[key]['max-age'] = max_age
# IE requires expires, so set it if hasn't been already.
if not expires:
self.cookies[key]['expires'] = cookie_date(time.time() +
max_age)
if path is not None:
self.cookies[key]['path'] = path
if domain is not None:
self.cookies[key]['domain'] = domain
if secure:
self.cookies[key]['secure'] = True
if httponly:
self.cookies[key]['httponly'] = True
def set_signed_cookie(self, key, value, salt='', **kwargs):
value = signing.get_cookie_signer(salt=key + salt).sign(value)
return self.set_cookie(key, value, **kwargs)
def delete_cookie(self, key, path='/', domain=None):
self.set_cookie(key, max_age=0, path=path, domain=domain,
expires='Thu, 01-Jan-1970 00:00:00 GMT')
# Common methods used by subclasses
def make_bytes(self, value):
"""Turn a value into a bytestring encoded in the output charset."""
# Per PEP 3333, this response body must be bytes. To avoid returning
# an instance of a subclass, this function returns `bytes(value)`.
# This doesn't make a copy when `value` already contains bytes.
# If content is already encoded (eg. gzip), assume bytes.
if self.has_header('Content-Encoding'):
return bytes(value)
# Handle string types -- we can't rely on force_bytes here because:
# - under Python 3 it attemps str conversion first
# - when self._charset != 'utf-8' it re-encodes the content
if isinstance(value, bytes):
return bytes(value)
if isinstance(value, six.text_type):
return bytes(value.encode(self._charset))
# Handle non-string types (#16494)
return force_bytes(value, self._charset)
def __iter__(self):
return self
def __next__(self):
# Subclasses must define self._iterator for this function.
return self.make_bytes(next(self._iterator))
next = __next__ # Python 2 compatibility
# These methods partially implement the file-like object interface.
# See http://docs.python.org/lib/bltin-file-objects.html
# The WSGI server must call this method upon completion of the request.
# See http://blog.dscpl.com.au/2012/10/obligations-for-calling-close-on.html
def close(self):
for closable in self._closable_objects:
closable.close()
def write(self, content):
raise Exception("This %s instance is not writable" % self.__class__.__name__)
def flush(self):
pass
def tell(self):
raise Exception("This %s instance cannot tell its position" % self.__class__.__name__)
class HttpResponse(HttpResponseBase):
"""
An HTTP response class with a string as content.
This content that can be read, appended to or replaced.
"""
streaming = False
def __init__(self, content='', *args, **kwargs):
super(HttpResponse, self).__init__(*args, **kwargs)
# Content is a bytestring. See the `content` property methods.
self.content = content
def serialize(self):
"""Full HTTP message, including headers, as a bytestring."""
return self.serialize_headers() + b'\r\n\r\n' + self.content
if six.PY3:
__bytes__ = serialize
else:
__str__ = serialize
def _consume_content(self):
# If the response was instantiated with an iterator, when its content
# is accessed, the iterator is going be exhausted and the content
# loaded in memory. At this point, it's better to abandon the original
# iterator and save the content for later reuse. This is a temporary
# solution. See the comment in __iter__ below for the long term plan.
if self._base_content_is_iter:
self.content = b''.join(self.make_bytes(e) for e in self._container)
@property
def content(self):
self._consume_content()
return b''.join(self.make_bytes(e) for e in self._container)
@content.setter
def content(self, value):
if hasattr(value, '__iter__') and not isinstance(value, (bytes, six.string_types)):
self._container = value
self._base_content_is_iter = True
if hasattr(value, 'close'):
self._closable_objects.append(value)
else:
self._container = [value]
self._base_content_is_iter = False
def __iter__(self):
# Raise a deprecation warning only if the content wasn't consumed yet,
# because the response may be intended to be streamed.
# Once the deprecation completes, iterators should be consumed upon
# assignment rather than upon access. The _consume_content method
# should be removed. See #6527.
if self._base_content_is_iter:
warnings.warn(
'Creating streaming responses with `HttpResponse` is '
'deprecated. Use `StreamingHttpResponse` instead '
'if you need the streaming behavior.',
PendingDeprecationWarning, stacklevel=2)
if not hasattr(self, '_iterator'):
self._iterator = iter(self._container)
return self
def write(self, content):
self._consume_content()
self._container.append(content)
def tell(self):
self._consume_content()
return len(self.content)
class StreamingHttpResponse(HttpResponseBase):
"""
A streaming HTTP response class with an iterator as content.
This should only be iterated once, when the response is streamed to the
client. However, it can be appended to or replaced with a new iterator
that wraps the original content (or yields entirely new content).
"""
streaming = True
def __init__(self, streaming_content=(), *args, **kwargs):
super(StreamingHttpResponse, self).__init__(*args, **kwargs)
# `streaming_content` should be an iterable of bytestrings.
# See the `streaming_content` property methods.
self.streaming_content = streaming_content
@property
def content(self):
raise AttributeError("This %s instance has no `content` attribute. "
"Use `streaming_content` instead." % self.__class__.__name__)
@property
def streaming_content(self):
return map(self.make_bytes, self._iterator)
@streaming_content.setter
def streaming_content(self, value):
# Ensure we can never iterate on "value" more than once.
self._iterator = iter(value)
if hasattr(value, 'close'):
self._closable_objects.append(value)
class CompatibleStreamingHttpResponse(StreamingHttpResponse):
"""
This class maintains compatibility with middleware that doesn't know how
to handle the content of a streaming response by exposing a `content`
attribute that will consume and cache the content iterator when accessed.
These responses will stream only if no middleware attempts to access the
`content` attribute. Otherwise, they will behave like a regular response,
and raise a `PendingDeprecationWarning`.
"""
@property
def content(self):
warnings.warn(
'Accessing the `content` attribute on a streaming response is '
'deprecated. Use the `streaming_content` attribute instead.',
PendingDeprecationWarning)
content = b''.join(self)
self.streaming_content = [content]
return content
@content.setter
def content(self, content):
warnings.warn(
'Accessing the `content` attribute on a streaming response is '
'deprecated. Use the `streaming_content` attribute instead.',
PendingDeprecationWarning)
self.streaming_content = [content]
class HttpResponseRedirectBase(HttpResponse):
allowed_schemes = ['http', 'https', 'ftp']
def __init__(self, redirect_to, *args, **kwargs):
parsed = urlparse(redirect_to)
if parsed.scheme and parsed.scheme not in self.allowed_schemes:
raise SuspiciousOperation("Unsafe redirect to URL with protocol '%s'" % parsed.scheme)
super(HttpResponseRedirectBase, self).__init__(*args, **kwargs)
self['Location'] = iri_to_uri(redirect_to)
class HttpResponseRedirect(HttpResponseRedirectBase):
status_code = 302
class HttpResponsePermanentRedirect(HttpResponseRedirectBase):
status_code = 301
class HttpResponseNotModified(HttpResponse):
status_code = 304
def __init__(self, *args, **kwargs):
super(HttpResponseNotModified, self).__init__(*args, **kwargs)
del self['content-type']
@HttpResponse.content.setter
def content(self, value):
if value:
raise AttributeError("You cannot set content to a 304 (Not Modified) response")
self._container = []
self._base_content_is_iter = False
class HttpResponseBadRequest(HttpResponse):
status_code = 400
class HttpResponseNotFound(HttpResponse):
status_code = 404
class HttpResponseForbidden(HttpResponse):
status_code = 403
class HttpResponseNotAllowed(HttpResponse):
status_code = 405
def __init__(self, permitted_methods, *args, **kwargs):
super(HttpResponseNotAllowed, self).__init__(*args, **kwargs)
self['Allow'] = ', '.join(permitted_methods)
class HttpResponseGone(HttpResponse):
status_code = 410
class HttpResponseServerError(HttpResponse):
status_code = 500
class Http404(Exception):
pass