fix: construct InfluxDBError without http response

Author: wasted925

influxdb_client/client/exceptions.py

@@ -12,9 +12,14 @@ class InfluxDBError(Exception):
 
     def __init__(self, response: HTTPResponse):
         """Initialize the InfluxDBError handler."""
-        self.response = response
-        self.message = self._get_message(response)
-        self.retry_after = response.getheader('Retry-After')
+        if response is not None:
+            self.response = response
+            self.message = self._get_message(response)
+            self.retry_after = response.getheader('Retry-After')
+        else:
+            self.response = None
+            self.message = 'no response'
+            self.retry_after = None
         super().__init__(self.message)
 
     def _get_message(self, response):

tests/test_InfluxDBError.py

@@ -46,3 +46,9 @@ def test_message_get_retry_after(self):
         influx_db_error = InfluxDBError(response=HTTPResponse(reason="too many requests"))
         self.assertEqual("too many requests", str(influx_db_error))
         self.assertEqual(None, influx_db_error.retry_after)
+
+    def test_no_response(self):
+        influx_db_error = InfluxDBError(response=None)
+        self.assertEqual("no response", str(influx_db_error))
+        self.assertIsNone(influx_db_error.response)
+        self.assertIsNone(influx_db_error.retry_after)