Merge pull request #1668 from erdenezul/read_preference_parse

parse read_preference from conn_host #1665

tests/test_connection.py

@@ -364,6 +364,12 @@ class ConnectionTest(unittest.TestCase):
         date_doc = DateDoc.objects.first()
         self.assertEqual(d, date_doc.the_date)
 
+    def test_read_preference_from_parse(self):
+        if IS_PYMONGO_3:
+            from pymongo import ReadPreference
+            conn = connect(host="mongodb://a1.vpc,a2.vpc,a3.vpc/prod?readPreference=secondaryPreferred")
+            self.assertEqual(conn.read_preference, ReadPreference.SECONDARY_PREFERRED)
+
     def test_multiple_connection_settings(self):
         connect('mongoenginetest', alias='t1', host="localhost")