Merge pull request psf#124 from eads/master

apply heuristics more aggresively

Author: ionrock

cachecontrol/adapter.py

@@ -56,6 +56,10 @@ def build_response(self, request, response, from_cache=False):
         cached response
         """
         if not from_cache and request.method == 'GET':
+            # Check for any heuristics that might update headers
+            # before trying to cache.
+            if self.heuristic:
+                response = self.heuristic.apply(response)
 
             # apply any expiration heuristics
             if response.status == 304:
@@ -83,11 +87,6 @@ def build_response(self, request, response, from_cache=False):
             elif response.status == 301:
                 self.controller.cache_response(request, response)
             else:
-                # Check for any heuristics that might update headers
-                # before trying to cache.
-                if self.heuristic:
-                    response = self.heuristic.apply(response)
-
                 # Wrap the response file with a wrapper that will cache the
                 #   response when the stream has been consumed.
                 response._fp = CallbackFileWrapper(

tests/conftest.py

@@ -59,6 +59,9 @@ def update_etag(self, env, start_response):
         start_response('200 OK', headers)
         return [pformat(env).encode("utf8")]
 
+    def conditional_get(self, env, start_response):
+        return start_response('304 Not Modified', [])
+
     def etag(self, env, start_response):
         headers = [
             ('Etag', self.etag_string),

tests/test_expires_heuristics.py

@@ -36,6 +36,26 @@ def test_no_header_change_means_no_warning_header(self, url):
         assert not self.heuristic.warning.called
 
 
+class TestHeuristicWith3xxResponse(object):
+    def setup(self):
+
+        class DummyHeuristic(BaseHeuristic):
+            def update_headers(self, resp):
+                return {'x-dummy-header': 'foobar'}
+
+        self.sess = CacheControl(Session(), heuristic=DummyHeuristic())
+
+    def test_heuristic_applies_to_301(self, url):
+        the_url = url + 'permanent_redirect'
+        resp = self.sess.get(the_url)
+        assert 'x-dummy-header' in resp.headers
+
+    def test_heuristic_applies_to_304(self, url):
+        the_url = url + 'conditional_get'
+        resp = self.sess.get(the_url)
+        assert 'x-dummy-header' in resp.headers
+
+
 class TestUseExpiresHeuristic(object):
 
     def test_expires_heuristic_arg(self):