33 lines
1.1 KiB
Python
33 lines
1.1 KiB
Python
from django.utils.cache import get_conditional_response
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from django.utils.deprecation import MiddlewareMixin
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from django.utils.http import http_date, parse_http_date_safe
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class ConditionalGetMiddleware(MiddlewareMixin):
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"""
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Handles conditional GET operations. If the response has an ETag or
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Last-Modified header, and the request has If-None-Match or
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If-Modified-Since, the response is replaced by an HttpNotModified.
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Also sets the Date and Content-Length response-headers.
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"""
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def process_response(self, request, response):
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response['Date'] = http_date()
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if not response.streaming and not response.has_header('Content-Length'):
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response['Content-Length'] = str(len(response.content))
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etag = response.get('ETag')
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last_modified = response.get('Last-Modified')
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if last_modified:
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last_modified = parse_http_date_safe(last_modified)
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if etag or last_modified:
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return get_conditional_response(
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request,
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etag=etag,
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last_modified=last_modified,
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response=response,
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)
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return response
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