fix tags filter to retrieve specified tags not excluding specified tags (#34)

* fix tags filter to retrieve specified tags not excluding specified tags

* fix tests and return value when filters is empty

Author: José Carlos Ferreiro

pypingdom/client.py

@@ -43,8 +43,8 @@ def get_check(self, name=None, _id=None):
 
     def get_checks(self, filters=None):
         if filters is None:
-            filters = {}
-        return [c for c in self.checks.values() if len(set(filters.get("tags", [])).intersection(set([x['name']
+            return [c for c in self.checks.values()]
+        return [c for c in self.checks.values() if not len(set(filters.get("tags", [])).intersection(set([x['name']
                 for x in c.tags]))) == 0]
 
     def create_check(self, name, obj):

pypingdom/tests/test_client.py

@@ -70,4 +70,4 @@ def test_get_checks(self, m):
         self.assertTrue(all(isinstance(x, Check) for x in res))
 
         res = client.get_checks(filters={"tags": ['apache']})
-        self.assertEqual(len(res), 2)
+        self.assertEqual(len(res), 1)