Add a new OperationalError type support

backend/backend/utils.py

@@ -5,13 +5,23 @@
 from psycopg2 import OperationalError
 
 
+def starts_with_any(string, patterns_list):
+    for pattern in patterns_list:
+        if string.startswith(pattern):
+            return True
+    return False
+
+
 def ensure_connection_with_retries(self):
     """
     A function supposed to be used for patching the standard django database connection class' method
      in order to try to connect to DB multiple times using exponential backoff algorithm.
     After each consecutive connection error it waits 1, 2, 4, 8, 16, 32, ... seconds until success or
      the end of time allowed to spend on reconnection attempts.
     """
+    handled_errors_patterns = ('could not connect to server: Connection refused',
+                               'could not connect to server: No route to host'
+                               'could not translate host name')
 
     def custom_properties_cleanup(obj):
         delattr(obj, '_is_connecting')
@@ -28,8 +38,7 @@ def custom_properties_cleanup(obj):
                 self.connect()
             except OperationalError as e:
                 # We need to reconnect only after particular OperationalError types.
-                if e.args and (e.args[0].startswith('could not connect to server: Connection refused') or
-                               e.args[0].startswith('could not translate host name')):
+                if e.args and isinstance(e.args[0], str) and starts_with_any(e.args[0], handled_errors_patterns):
                     # Connection error.
                     if not hasattr(self, "_connection_retry"):
                         self._connection_retry = 0