Make RSS lookup caching more efficient

sickbeard/scene_exceptions.py

@@ -85,12 +85,21 @@ def retrieve_exceptions():
         exception_dict[tvdb_id] = alias_list
 
     myDB = db.DBConnection("cache.db")
-    myDB.action("DELETE FROM scene_exceptions WHERE 1=1")
+
+    changed_exceptions = False
 
     # write all the exceptions we got off the net into the database
     for cur_tvdb_id in exception_dict:
+
+        # get a list of the existing exceptions for this ID
+        existing_exceptions = [x["show_name"] for x in myDB.select("SELECT * FROM scene_exceptions WHERE tvdb_id = ?", [cur_tvdb_id])]
+        
         for cur_exception in exception_dict[cur_tvdb_id]:
+            # if this exception isn't already in the DB then add it
+            if cur_exception not in existing_exceptions:
                 myDB.action("INSERT INTO scene_exceptions (tvdb_id, show_name) VALUES (?,?)", [cur_tvdb_id, cur_exception])
+                changed_exceptions = True
 
     # since this could invalidate the results of the cache we clear it out after updating
+    if changed_exceptions:
         name_cache.clearCache()
\ No newline at end of file

tests/scene_helpers_tests.py

@@ -3,7 +3,7 @@ import unittest
 import sys, os.path
 sys.path.append(os.path.abspath('..'))
 
-from sickbeard import show_name_helpers, scene_exceptions, common
+from sickbeard import show_name_helpers, scene_exceptions, common, name_cache
 
 import sickbeard
 from sickbeard import db
@@ -108,6 +108,24 @@ class SceneExceptionTestCase(unittest.TestCase):
     def test_sceneExceptionByNameEmpty(self):
         self.assertEqual(scene_exceptions.get_scene_exception_by_name('nothing useful'), None)
 
+    def test_sceneExceptionsResetNameCache(self):
+        # clear the exceptions
+        myDB = db.DBConnection("cache.db")
+        myDB.action("DELETE FROM scene_exceptions")
+        
+        # put something in the cache
+        name_cache.addNameToCache('Cached Name', 0)
+        
+        # updating should clear the cache so our previously "Cached Name" won't be in there
+        scene_exceptions.retrieve_exceptions()
+        self.assertEqual(name_cache.retrieveNameFromCache('Cached Name'), None)
+
+        # put something in the cache
+        name_cache.addNameToCache('Cached Name', 0)
+        
+        # updating should not clear the cache this time since our exceptions didn't change
+        scene_exceptions.retrieve_exceptions()
+        self.assertEqual(name_cache.retrieveNameFromCache('Cached Name'), 0)
 
 
 if __name__ == '__main__':