add expires parameter to base class

cachecontrol/cache.py

@@ -14,7 +14,7 @@ class BaseCache(object):
     def get(self, key):
         raise NotImplementedError()
 
-    def set(self, key, value):
+    def set(self, key, value, expires=None):
         raise NotImplementedError()
 
     def delete(self, key):
@@ -33,7 +33,7 @@ def __init__(self, init_dict=None):
     def get(self, key):
         return self.data.get(key, None)
 
-    def set(self, key, value):
+    def set(self, key, value, expires=None):
         with self.lock:
             self.data.update({key: value})
 

cachecontrol/caches/file_cache.py

@@ -118,7 +118,7 @@ def get(self, key):
         except FileNotFoundError:
             return None
 
-    def set(self, key, value):
+    def set(self, key, value, expires=None):
         name = self._fn(key)
 
         # Make sure the directory exists

cachecontrol/controller.py

@@ -268,6 +268,13 @@ def cache_response(self, request, response, body=None, status_codes=None):
 
         response_headers = CaseInsensitiveDict(response.headers)
 
+        if 'date' in response_headers:
+            date = calendar.timegm(
+                parsedate_tz(response_headers['date'])
+            )
+        else:
+            date = 0
+
         # If we've been given a body, our response has a Content-Length, that
         # Content-Length is valid then we can check to see if the body we've
         # been given matches the expected size, and if it doesn't we'll just
@@ -311,9 +318,20 @@ def cache_response(self, request, response, body=None, status_codes=None):
 
         # If we've been given an etag, then keep the response
         if self.cache_etags and "etag" in response_headers:
+            expires_time = 0
+            if response_headers.get('expires'):
+                expires = parsedate_tz(response_headers['expires'])
+                if expires is not None:
+                    expires_time = calendar.timegm(expires) - date
+
+            expires_time = max(expires_time, 14 * 86400)
+
+            logger.debug('etag object cached for {0} seconds'.format(expires_time))
             logger.debug("Caching due to etag")
             self.cache.set(
-                cache_url, self.serializer.dumps(request, response, body)
+                cache_url,
+                self.serializer.dumps(request, response, body),
+                expires=expires_time
             )
 
         # Add to the cache any permanent redirects. We do this before looking
@@ -326,20 +344,34 @@ def cache_response(self, request, response, body=None, status_codes=None):
         # is no date header then we can't do anything about expiring
         # the cache.
         elif "date" in response_headers:
+            date = calendar.timegm(
+                parsedate_tz(response_headers['date'])
+            )
             # cache when there is a max-age > 0
             if "max-age" in cc and cc["max-age"] > 0:
                 logger.debug("Caching b/c date exists and max-age > 0")
+                expires_time = cc['max-age']
                 self.cache.set(
-                    cache_url, self.serializer.dumps(request, response, body)
+                    cache_url,
+                    self.serializer.dumps(request, response, body),
+                    expires=expires_time
                 )
 
             # If the request can expire, it means we should cache it
             # in the meantime.
             elif "expires" in response_headers:
                 if response_headers["expires"]:
-                    logger.debug("Caching b/c of expires header")
+                    expires = parsedate_tz(response_headers['expires'])
+                    if expires is not None:
+                        expires_time = calendar.timegm(expires) - date
+                    else:
+                        expires_time = None
+
+                    logger.debug('Caching b/c of expires header. expires in {0} seconds'.format(expires_time))
                     self.cache.set(
-                        cache_url, self.serializer.dumps(request, response, body)
+                        cache_url,
+                        self.serializer.dumps(request, response, body=body),
+                        expires=expires_time,
                     )
 
     def update_cached_response(self, request, response):

tests/test_cache_control.py

@@ -87,7 +87,7 @@ def test_cache_response_cache_max_age(self, cc):
         req = self.req()
         cc.cache_response(req, resp)
         cc.serializer.dumps.assert_called_with(req, resp, None)
-        cc.cache.set.assert_called_with(self.url, ANY)
+        cc.cache.set.assert_called_with(self.url, ANY, expires=3600)
 
     def test_cache_response_cache_max_age_with_invalid_value_not_cached(self, cc):
         now = time.strftime(TIME_FMT, time.gmtime())