def _get_conditional_response(self, request, etag, last_modified):
"""Mimics ConditionalGetMiddleware"""
return get_conditional_response(
request,
etag=etag,
last_modified=last_modified,
)
def process_response(self, request, response):
"""
Calculate the ETag, if needed.
When the status code of the response is 404, it may redirect to a path
with an appended slash if should_redirect_with_slash() returns True.
"""
# If the given URL is "Not Found", then check if we should redirect to
# a path with a slash appended.
if response.status_code == 404:
if self.should_redirect_with_slash(request):
return self.response_redirect_class(
self.get_full_path_with_slash(request))
if settings.USE_ETAGS:
if not response.has_header('ETag'):
set_response_etag(response)
if response.has_header('ETag'):
return get_conditional_response(
request,
etag=response['ETag'],
response=response,
)
return response
def process_response(self, request, response):
"""
Calculate the ETag, if needed.
When the status code of the response is 404, it may redirect to a path
with an appended slash if should_redirect_with_slash() returns True.
"""
# If the given URL is "Not Found", then check if we should redirect to
# a path with a slash appended.
if response.status_code == 404:
if self.should_redirect_with_slash(request):
return self.response_redirect_class(self.get_full_path_with_slash(request))
if settings.USE_ETAGS and self.needs_etag(response):
if not response.has_header('ETag'):
set_response_etag(response)
if response.has_header('ETag'):
return get_conditional_response(
request,
etag=response['ETag'],
response=response,
)
# Add the Content-Length header to non-streaming responses if not
# already set.
if not response.streaming and not response.has_header('Content-Length'):
response['Content-Length'] = str(len(response.content))
return response
def inner(request, *args, **kwargs):
# Compute values (if any) for the requested resource.
def get_last_modified():
if last_modified_func:
dt = last_modified_func(request, *args, **kwargs)
if dt:
return timegm(dt.utctimetuple())
# The value from etag_func() could be quoted or unquoted.
res_etag = etag_func(request, *args, **kwargs) if etag_func else None
res_etag = quote_etag(res_etag) if res_etag is not None else None
res_last_modified = get_last_modified()
response = get_conditional_response(
request,
etag=res_etag,
last_modified=res_last_modified,
)
if response is None:
response = func(request, *args, **kwargs)
# Set relevant headers on the response if they don't already exist
# and if the request method is safe.
if request.method in ('GET', 'HEAD'):
if res_last_modified and not response.has_header('Last-Modified'):
response['Last-Modified'] = http_date(res_last_modified)
if res_etag:
response.setdefault('ETag', res_etag)
return response
def inner(request, *args, **kwargs):
# Compute values (if any) for the requested resource.
def get_last_modified():
if last_modified_func:
dt = last_modified_func(request, *args, **kwargs)
if dt:
if not timezone.is_aware(dt):
dt = timezone.make_aware(dt, datetime.timezone.utc)
return int(dt.timestamp())
# The value from etag_func() could be quoted or unquoted.
res_etag = etag_func(request, *args, **kwargs) if etag_func else None
res_etag = quote_etag(res_etag) if res_etag is not None else None
res_last_modified = get_last_modified()
response = get_conditional_response(
request,
etag=res_etag,
last_modified=res_last_modified,
)
if response is None:
response = func(request, *args, **kwargs)
# Set relevant headers on the response if they don't already exist
# and if the request method is safe.
if request.method in ("GET", "HEAD"):
if res_last_modified and not response.has_header("Last-Modified"):
response.headers["Last-Modified"] = http_date(res_last_modified)
if res_etag:
response.headers.setdefault("ETag", res_etag)
return response
def detail_view(self, request, **kwargs):
# Exit early if there are any issues
self.check_parameter_validity()
if helpers.is_draft_requested(request):
return super().detail_view(request, pk=None)
# Return a cached response if one is available
cached_data = cache.PageCache.get(
page_id=self.get_object_id(),
lang=translation.get_language(),
region=request.GET.get('region'),
)
if cached_data:
cached_response = helpers.CachedResponse(cached_data)
cached_response['etag'] = cached_data.get('etag', None)
return get_conditional_response(
request=request,
etag=cached_response['etag'],
response=cached_response,
)
# No cached response available
response = super().detail_view(request, pk=None)
if response.status_code == 200:
# Reuse the already-fetched object to populate the cache
cache.CachePopulator.populate_async(self.get_object())
# No etag is set for this response because creating one is expensive.
# If API caching is enabled, one will be added to the cached version
# created above.
return response
def inner(request, *args, **kwargs):
# Compute values (if any) for the requested resource.
def get_last_modified():
if last_modified_func:
dt = last_modified_func(request, *args, **kwargs)
if dt:
return timegm(dt.utctimetuple())
# The value from etag_func() could be quoted or unquoted.
res_etag = etag_func(request, *args, **kwargs) if etag_func else None
res_etag = quote_etag(res_etag) if res_etag is not None else None
res_last_modified = get_last_modified()
response = get_conditional_response(
request,
etag=res_etag,
last_modified=res_last_modified,
)
if response is None:
response = func(request, *args, **kwargs)
# Set relevant headers on the response if they don't already exist
# and if the request method is safe.
if request.method in ('GET', 'HEAD'):
if res_last_modified and not response.has_header('Last-Modified'):
response['Last-Modified'] = http_date(res_last_modified)
if res_etag:
response.setdefault('ETag', res_etag)
return response
def wrapped_func(self, request, *args, **kwargs):
response_format = self.perform_content_negotiation(request)[0].format
etag_user = (':'+str(request.user.pk or 0)) if response_format == 'api' else ''
raw_etag = '%s%s:%s:%s' % (response_format, etag_user, get_language(),
(etag_func(request) if permissions else MapUpdate.current_cache_key()))
if base_mapdata_check and self.base_mapdata:
raw_etag += ':%d' % request.user_permissions.can_access_base_mapdata
etag = quote_etag(raw_etag)
response = get_conditional_response(request, etag=etag)
if response is None:
cache_key = 'mapdata:api:'+request.path_info[5:].replace('/', '-').strip('-')+':'+raw_etag
if cache_parameters is not None:
for param, type_ in cache_parameters.items():
value = int(param in request.GET) if type_ == bool else type_(request.GET.get(param))
cache_key += ':'+urlsafe_base64_encode(str(value).encode()).decode()
data = request_cache.get(cache_key)
if data is not None:
response = Response(data)
if response is None:
with GeometryMixin.dont_keep_originals():
response = func(self, request, *args, **kwargs)
if cache_parameters is not None and response.status_code == 200:
request_cache.set(cache_key, response.data, 900)
if response.status_code == 200:
response['ETag'] = etag
response['Cache-Control'] = 'no-cache'
return response
def get(self, request, *args, **kwargs):
"""Mixin implementation of django.views.decorators.http.condition"""
# Resolve etag and last_modified
etag = self.get_etag(request)
etag = quote_etag(etag) if etag is not None else None
last_modified = self.get_last_modified(request)
last_modified = timegm(
last_modified.utctimetuple()) if last_modified else None
# Check request headers
response = get_conditional_response(request,
etag=etag,
last_modified=last_modified)
if response:
return response
# If we need get new data, do that
response = super().get(request, *args, **kwargs)
# Set relevant headers on the response if they don't already exist.
if last_modified and not response.has_header('Last-Modified'):
response['Last-Modified'] = http_date(last_modified)
if etag and not response.has_header('ETag'):
response['ETag'] = etag
return response
def dispatch(self, *args, **kwargs):
if ('service_name' not in self.request.GET
or helpers.is_draft_requested(self.request)):
return super().dispatch(*args, **kwargs)
cached_page = cache.PageCache.get(slug=self.kwargs['slug'],
params={
'service_name':
self.request.GET['service_name'],
'lang':
translation.get_language(),
'region':
self.request.GET.get('region'),
})
if cached_page:
cached_response = helpers.CachedResponse(cached_page)
cached_response['etag'] = cached_page.get('etag', None)
response = get_conditional_response(
request=self.request,
etag=cached_response['etag'],
response=cached_response,
)
else:
response = super().dispatch(*args, **kwargs)
if response.status_code == 200:
# No etag is set in this response. this is because creating an
# etag is expensive. It will be present on the next retrieved
# from the cache though.
cache.CachePopulator.populate_async(self.get_object())
return response
def process_response(self, request, response):
"""
Calculate the ETag, if needed.
When the status code of the response is 404, it may redirect to a path
with an appended slash if should_redirect_with_slash() returns True.
"""
# If the given URL is "Not Found", then check if we should redirect to
# a path with a slash appended.
if response.status_code == 404:
if self.should_redirect_with_slash(request):
return self.response_redirect_class(
self.get_full_path_with_slash(request))
if settings.USE_ETAGS and self.needs_etag(response):
if not response.has_header('ETag'):
set_response_etag(response)
if response.has_header('ETag'):
return get_conditional_response(
request,
etag=unquote_etag(response['ETag']),
response=response,
)
# Add the Content-Length header to non-streaming responses if not
# already set.
if not response.streaming and not response.has_header(
'Content-Length'):
response['Content-Length'] = str(len(response.content))
return response
def inner(request, *args, **kwargs):
# Compute values (if any) for the requested resource.
def get_last_modified():
if last_modified_func:
dt = last_modified_func(request, *args, **kwargs)
if dt:
return timegm(dt.utctimetuple())
res_etag = etag_func(request, *args, **
kwargs) if etag_func else None
res_last_modified = get_last_modified()
response = get_conditional_response(
request,
etag=res_etag,
last_modified=res_last_modified,
)
if response is None:
response = func(request, *args, **kwargs)
# Set relevant headers on the response if they don't already exist.
if res_last_modified and not response.has_header('Last-Modified'):
response['Last-Modified'] = http_date(res_last_modified)
if res_etag and not response.has_header('ETag'):
response['ETag'] = quote_etag(res_etag)
return response
def process_response(self, request, response):
if not response.streaming and not response.has_header('Content-Length'):
response['Content-Length'] = str(len(response.content))
# It's too late to prevent an unsafe request with a 412 response, and
# for a HEAD request, the response body is always empty so computing
# an accurate ETag isn't possible.
if request.method != 'GET':
return response
if self.needs_etag(response) and not response.has_header('ETag'):
set_response_etag(response)
etag = response.get('ETag')
last_modified = response.get('Last-Modified')
if last_modified:
last_modified = parse_http_date_safe(last_modified)
if etag or last_modified:
return get_conditional_response(
request,
etag=etag,
last_modified=last_modified,
response=response,
)
return response
def __call__(self, request: HttpRequest):
if settings.DEBUG:
response = self.get_response(request)
response['Cache-Control'] = 'max-age=0, private, must-revalidate'
response[SFI_CACHE_HEADER] = 'DEBUG_BYPASS'
return response
if not request.path.startswith(
PAGE_CACHE_URLS) or not self._is_request_cacheable(request):
response = self.get_response(request)
response['Cache-Control'] = 'max-age=0, private, must-revalidate'
response[SFI_CACHE_HEADER] = 'BYPASS'
return response
last_modified = get_last_modified_stamp()
last_modified_stamp, etag = get_last_modified_and_etag(request)
# Try getting a Not Modified response.
response = get_conditional_response(
request, etag, timegm(last_modified.utctimetuple()))
if response:
response[SFI_CACHE_HEADER] = 'NON_MODIFIED'
return response
# Lookup cache
entry = self._try_get_cache(request)
if entry and entry.created_date > last_modified:
response = entry.response
response[SFI_CACHE_HEADER] = 'HIT'
return response
request._cache_update_cache = True
response = self.get_response(request)
response[SFI_CACHE_HEADER] = 'MISS'
return response
def wrapped_func(self, request, *args, **kwargs):
response_format = self.perform_content_negotiation(
request)[0].format
etag_user = (
':' +
str(request.user.pk or 0)) if response_format == 'api' else ''
raw_etag = '%s%s:%s:%s' % (response_format, etag_user,
get_language(),
(etag_func(request) if permissions else
MapUpdate.current_cache_key()))
etag = quote_etag(raw_etag)
response = get_conditional_response(request, etag=etag)
if response is None:
cache_key = 'mapdata:api:' + request.path_info[5:].replace(
'/', '-').strip('-') + ':' + raw_etag
if cache_parameters is not None:
for param, type_ in cache_parameters.items():
value = int(
param in request.GET) if type_ == bool else type_(
request.GET.get(param))
cache_key += ':' + urlsafe_base64_encode(
str(value).encode()).decode()
data = cache.get(cache_key)
if data is not None:
response = Response(data)
if response is None:
response = func(self, request, *args, **kwargs)
if cache_parameters is not None and response.status_code == 200:
cache.set(cache_key, response.data, 300)
response['ETag'] = etag
response['Cache-Control'] = 'no-cache'
return response
def inner(request, *args, **kwargs):
# Compute values (if any) for the requested resource.
def get_last_modified():
if last_modified_func:
dt = last_modified_func(request, *args, **kwargs)
if dt:
return timegm(dt.utctimetuple())
res_etag = etag_func(request, *args, **kwargs) if etag_func else None
res_last_modified = get_last_modified()
response = get_conditional_response(
request,
etag=res_etag,
last_modified=res_last_modified,
)
if response is None:
response = func(request, *args, **kwargs)
# Set relevant headers on the response if they don't already exist.
if res_last_modified and not response.has_header('Last-Modified'):
response['Last-Modified'] = http_date(res_last_modified)
if res_etag and not response.has_header('ETag'):
response['ETag'] = quote_etag(res_etag)
return response
def process_response(self, request, response):
"""
Calculate the ETag, if needed.
When the status code of the response is 404, it may redirect to a path
with an appended slash if should_redirect_with_slash() returns True.
"""
# If the given URL is "Not Found", then check if we should redirect to
# a path with a slash appended.
if response.status_code == 404:
if self.should_redirect_with_slash(request):
return self.response_redirect_class(self.get_full_path_with_slash(request))
if settings.USE_ETAGS:
if not response.has_header('ETag'):
set_response_etag(response)
if response.has_header('ETag'):
return get_conditional_response(
request,
etag=unquote_etag(response['ETag']),
response=response,
)
return response
def _image(self, request, pk=None):
source = self.get_object()
last_modified = int(os.path.getmtime(source.filepath))
response = get_conditional_response(request, last_modified=last_modified)
if response is None:
response = HttpResponse(open(source.filepath, 'rb'), content_type=mimetypes.guess_type(source.name)[0])
response['Last-Modified'] = http_date(last_modified)
return response
def condition_response(self, request):
instance = self.get_object()
last_modified = getattr(instance, "last_modified_on", None)
return get_conditional_response(
request,
etag=None,
last_modified=last_modified,
)
def fetch_query_results(request, name):
if request.method == "OPTIONS":
response = HttpResponse(status=204)
else:
if name == "single_card_details" and \
"HTTP_X_TWITCH_EXTENSION_VERSION" not in request.META:
# 2017-01-18 emergency fix
return HttpResponse(status=204)
parameterized_query = _get_query_and_params(request, name)
if issubclass(parameterized_query.__class__, HttpResponse):
return parameterized_query
last_modified = parameterized_query.result_as_of
if last_modified:
last_modified = timegm(last_modified.utctimetuple())
response = None
is_cache_hit = parameterized_query.result_available
if is_cache_hit:
_trigger_if_stale(parameterized_query)
# Try to return a minimal response
response = get_conditional_response(request,
last_modified=last_modified)
if not response:
if request.method == "HEAD":
response = HttpResponse(204)
else:
# Resort to a full response
response = _fetch_query_results(parameterized_query,
user=request.user)
# Add Last-Modified header
if response.status_code in (200, 204, 304):
response["Last-Modified"] = http_date(last_modified)
# Add Cache-Control headers
if parameterized_query.is_personalized or parameterized_query.has_premium_values:
patch_cache_control(response, no_cache=True, private=True)
else:
patch_cache_control(response, no_cache=True, public=True)
# Add CORS header if permitted - can be replaced by middleware in future
origin = urlparse(request.META.get("HTTP_ORIGIN", ""))
if origin.netloc in settings.ANALYTICS_CORS_ORIGIN_WHITELIST:
response["Access-Control-Allow-Origin"] = origin.geturl()
response["Access-Control-Allow-Methods"] = "GET, HEAD, OPTIONS"
response["Access-Control-Allow-Headers"] = ", ".join(
settings.ANALYTICS_CORS_HEADER_WHITELIST)
# Always patch vary header so browsers do not cache CORS
patch_vary_headers(response, ["Origin"])
return response
def _image(self, request, pk=None):
source = self.get_object()
last_modified = int(os.path.getmtime(source.filepath))
response = get_conditional_response(request,
last_modified=last_modified)
if response is None:
response = HttpResponse(open(source.filepath, 'rb'),
content_type=mimetypes.guess_type(
source.name)[0])
response['Last-Modified'] = http_date(last_modified)
return response
def process_response(self, request, response):
if (not response.streaming
and not response.has_header('Content-Length')):
response['Content-Length'] = str( # pragma: no cover
len(response.content))
etag = response.get('ETag')
if etag:
return get_conditional_response(
request,
etag=unquote_etag(etag),
response=response,
)
return response
def dispatch(self, request, *args, **kwargs):
response = super(LastModifiedMixin, self).dispatch(request, *args, **kwargs)
# NOTE: remove microseconds so that comparison will pass,
# since microseconds are not included in the last-modified header
last_modified = self.last_modified()
if last_modified:
last_modified = self.last_modified().replace(microsecond=0)
response['Last-Modified'] = last_modified.strftime('%a, %d %b %Y %H:%M:%S GMT')
last_modified = last_modified.timestamp()
return get_conditional_response(request,
last_modified=last_modified, response=response)
def process_response(self, request, response):
response["Date"] = http_date()
if not response.streaming and not response.has_header("Content-Length"):
response["Content-Length"] = str(len(response.content))
etag = response.get("ETag")
last_modified = response.get("Last-Modified")
if last_modified:
last_modified = parse_http_date_safe(last_modified)
if etag or last_modified:
return get_conditional_response(request, etag=etag, last_modified=last_modified, response=response)
return response
def process_request(self, request):
self.key_prefix = self.get_key_prefix(request)
request._cache_cache_timeout = int(self.cache_timeout)
response = super().process_request(request)
if response:
etag = response.get('ETag')
last_modified = response.get('Last-Modified')
if not (etag or last_modified):
return response
response = get_conditional_response(
request,
etag=etag,
last_modified=last_modified and parse_http_date_safe(last_modified),
response=response,
)
response['Last-Modified'] = last_modified
return response
def view_func(request, **kwargs):
response = real_view_func(request, **kwargs)
if request.method != 'GET':
return response
etag = response.get('ETag')
last_modified = response.get('Last-Modified')
if last_modified:
last_modified = parse_http_date_safe(last_modified)
if etag or last_modified:
return get_conditional_response(
request,
etag=etag,
last_modified=last_modified,
response=response,
)
return response
def process_response(self, request, response):
response['Date'] = http_date()
if not response.streaming and not response.has_header('Content-Length'):
response['Content-Length'] = str(len(response.content))
etag = response.get('ETag')
last_modified = response.get('Last-Modified')
if last_modified:
last_modified = parse_http_date_safe(last_modified)
if etag or last_modified:
return get_conditional_response(
request,
etag=unquote_etag(etag),
last_modified=last_modified,
response=response,
)
return response
def _wrapped_view_func(request, *args, **kwargs):
response = view_func(request, *args, **kwargs)
# no cache but allow store for etag compare
patch_cache_control(response, private=True, no_cache=True, max_age=0)
# conditonal response on GET and HEAD only
if request.method not in ('GET', 'HEAD'):
return response
# set etag
set_response_etag(response)
etag = response.get('ETag')
# conditonal response
return get_conditional_response(request,
etag=etag,
last_modified=None,
response=response)
def process_response(self, request, response):
response['Date'] = http_date()
if not response.streaming and not response.has_header('Content-Length'):
response['Content-Length'] = str(len(response.content))
etag = response.get('ETag')
last_modified = response.get('Last-Modified')
if last_modified:
last_modified = parse_http_date_safe(last_modified)
if etag or last_modified:
return get_conditional_response(
request,
etag=etag,
last_modified=last_modified,
response=response,
)
return response
def get_conditional_response(request, response=None):
if not (response and hasattr(cache, 'get_conditional_response')):
# Django 1.8 does not have such method, can't do anything
return response
last_modified = response.get('Last-Modified')
conditional_response = cache.get_conditional_response(
request,
last_modified=http.parse_http_date_safe(last_modified),
response=response,
)
if conditional_response is response:
return response
headers = {
header: response[header]
for header in rfc7232_headers
if header in response
}
for header, value in headers.items():
conditional_response[header] = value
return conditional_response
def dispatch(self, request, *args, **kwargs):
# NOTE: this doesn't actually skip view processing,
# but without it we could return a not modified for a non-200 response
response = super(LastModifiedMixin,
self).dispatch(request, *args, **kwargs)
last_modified = self.last_modified()
if last_modified:
# remove microseconds so that comparison will pass,
# since microseconds are not included in the last-modified header
last_modified = self.last_modified().replace(microsecond=0)
response['Last-Modified'] = last_modified.strftime(
'%a, %d %b %Y %H:%M:%S GMT')
# convert the same way django does so that they will
# compare correctly
last_modified = calendar.timegm(last_modified.utctimetuple())
return get_conditional_response(request,
last_modified=last_modified,
response=response)
def process_response(self, request, response):
# It's too late to prevent an unsafe request with a 412 response, and
# for a HEAD request, the response body is always empty so computing
# an accurate ETag isn't possible.
if request.method != "GET":
return response
if self.needs_etag(response) and not response.has_header("ETag"):
set_response_etag(response)
etag = response.get("ETag")
last_modified = response.get("Last-Modified")
last_modified = last_modified and parse_http_date_safe(last_modified)
if etag or last_modified:
return get_conditional_response(request,
etag=etag,
last_modified=last_modified,
response=response)
return response
def process_response(self, request, response):
# 加上时间头
response['Date'] = http_date()
# 不是文件流并且没有长度header则补上
if not response.streaming and not response.has_header('Content-Length'):
response['Content-Length'] = str(len(response.content))
# 获得本次response的内容标示ETag
etag = response.get('ETag')
last_modified = response.get('Last-Modified')
if last_modified:
last_modified = parse_http_date_safe(last_modified)
if etag or last_modified:
return get_conditional_response(
request,
etag=unquote_etag(etag),
last_modified=last_modified,
response=response,
)
return response
def process_response(self, request, response):
"""
Calculate the ETag, if needed.
When the status code of the response is 404, it may redirect to a path
with an appended slash if should_redirect_with_slash() returns True.
"""
# If the given URL is "Not Found", then check if we should redirect to
# a path with a slash appended.
if response.status_code == 404:
if self.should_redirect_with_slash(request):
return self.response_redirect_class(
self.get_full_path_with_slash(request))
if settings.USE_ETAGS and self.needs_etag(response):
warnings.warn(
"The USE_ETAGS setting is deprecated in favor of "
"ConditionalGetMiddleware which sets the ETag regardless of "
"the setting. CommonMiddleware won't do ETag processing in "
"Django 2.1.",
RemovedInDjango21Warning,
)
if not response.has_header("ETag"):
set_response_etag(response)
if response.has_header("ETag"):
return get_conditional_response(
request,
etag=response["ETag"],
response=response,
)
# Add the Content-Length header to non-streaming responses if not
# already set.
if not response.streaming and not response.has_header(
"Content-Length"):
response["Content-Length"] = str(len(response.content))
return response
def detail_view(self, request, **kwargs):
# Exit early if there are any issues
self.check_parameter_validity()
draft_version = helpers.is_draft_requested(request)
langs = []
if translation.get_language():
langs.append(translation.get_language())
langs.append('en-gb')
# Return a cached response if one is available
for lang in langs:
cached_data = cache.PageCache.get(page_id=self.object_id, lang=lang, draft_version=draft_version)
if cached_data:
cached_response = helpers.CachedResponse(cached_data)
cached_response['etag'] = cached_data.get('etag', None)
return get_conditional_response(
request=request,
etag=cached_response['etag'],
response=cached_response,
)
logger.warn('Page cache miss')
page = self.get_object()
if type(page) not in MODELS_SERIALIZERS_MAPPING:
# page that exists has been requested, but it's not serializable. E.g, it's a folder page
return Response(status=204)
else:
cache.CachePopulator.populate_async(self.get_object())
# super().detail_view can take several seconds due to unoptimized database reads - so lots of
# resources get used but ultimately will timeout
return Response(status=501)
def get(self, request, *args, **kwargs):
"""Mixin implementation of django.views.decorators.http.condition"""
# Resolve etag and last_modified
etag = self.get_etag(request)
etag = quote_etag(etag) if etag is not None else None
last_modified = self.get_last_modified(request)
last_modified = timegm(last_modified.utctimetuple()) if last_modified else None
# Check request headers
response = get_conditional_response(request, etag=etag, last_modified=last_modified)
if response:
return response
# If we need get new data, do that
response = super().get(request, *args, **kwargs)
# Set relevant headers on the response if they don't already exist.
if last_modified and not response.has_header('Last-Modified'):
response['Last-Modified'] = http_date(last_modified)
if etag and not response.has_header('ETag'):
response['ETag'] = etag
return response
def process_response(self, request, response):
"""
Calculate the ETag, if needed.
When the status code of the response is 404, it may redirect to a path
with an appended slash if should_redirect_with_slash() returns True.
"""
# If the given URL is "Not Found", then check if we should redirect to
# a path with a slash appended.
if response.status_code == 404:
if self.should_redirect_with_slash(request):
return self.response_redirect_class(self.get_full_path_with_slash(request))
if settings.USE_ETAGS and self.needs_etag(response):
warnings.warn(
"The USE_ETAGS setting is deprecated in favor of "
"ConditionalGetMiddleware which sets the ETag regardless of "
"the setting. CommonMiddleware won't do ETag processing in "
"Django 2.1.",
RemovedInDjango21Warning
)
if not response.has_header('ETag'):
set_response_etag(response)
if response.has_header('ETag'):
return get_conditional_response(
request,
etag=response['ETag'],
response=response,
)
# Add the Content-Length header to non-streaming responses if not
# already set.
if not response.streaming and not response.has_header('Content-Length'):
response['Content-Length'] = str(len(response.content))
return response
import logging
def not_modified(request, etag=None, last_modified=None):
return get_conditional_response(
request,
etag=etag,
last_modified=timegm(last_modified.utctimetuple())
) is not None
from django.utils.cache import get_conditional_response
