fix: Fixed serialization of DataFrame with empty (NaN) values #118

Author: rolincova

influxdb_client/client/write/dataframe_serializer.py

@@ -72,15 +72,18 @@ def data_frame_to_list_of_points(data_frame, point_settings, **kwargs):
         key_format = f'{{keys[{index}]}}'
 
         if key in data_frame_tag_columns:
-            tags.append(f"{key_format}={{str(p[{index + 1}]).translate(_ESCAPE_KEY)}}")
+            tags.append({'key': key, 'value': f"{key_format}={{str(p[{index + 1}]).translate(_ESCAPE_KEY)}}"})
         elif issubclass(value.type, np.integer):
             fields.append(f"{key_format}={{p[{index + 1}]}}i")
         elif issubclass(value.type, (np.float, np.bool_)):
             fields.append(f"{key_format}={{p[{index + 1}]}}")
         else:
             fields.append(f"{key_format}=\"{{str(p[{index + 1}]).translate(_ESCAPE_KEY)}}\"")
 
-    fmt = (f'{{measurement_name}}', f'{"," if tags else ""}', ','.join(tags),
+    tags.sort(key=lambda x: x['key'])
+    tags = ','.join(map(lambda y: y['value'], tags))
+
+    fmt = (f'{{measurement_name}}', f'{"," if tags else ""}', tags,
            ' ', ','.join(fields), ' {p[0].value}')
     f = eval("lambda p: f'{}'".format(''.join(fmt)),
              {'measurement_name': measurement_name, '_ESCAPE_KEY': _ESCAPE_KEY, 'keys': keys})
@@ -97,4 +100,4 @@ def data_frame_to_list_of_points(data_frame, point_settings, **kwargs):
               for p in _itertuples(data_frame))
         return list(lp)
     else:
-        return list(map(f, _itertuples(data_frame)))
+        return list(map(f, _itertuples(data_frame)))

tests/test_WriteApiDataFrame.py

@@ -197,3 +197,20 @@ def test_tag_escaping_key_and_value(self):
         self.assertEqual(
             "h\\n2\\ro\\t_data,carriage\\rreturn=carriage\\nreturn,new\\nline=new\\nline,t\\tab=t\\tab l\\ne\\rv\\tel=2i 1586048400000000000",
             points[0])
+
+    def test_tags_order(self):
+        from influxdb_client.extras import pd, np
+
+        now = pd.Timestamp('2020-04-05 00:00+00:00')
+
+        data_frame = pd.DataFrame(data=[["c", "a", "b", np.int64(2)], ],
+                                  index=[now + timedelta(hours=1), ],
+                                  columns=["c", "a", "b", "level"])
+
+        points = data_frame_to_list_of_points(data_frame=data_frame,
+                                              point_settings=PointSettings(),
+                                              data_frame_measurement_name='h2o',
+                                              data_frame_tag_columns={"c", "a", "b"})
+
+        self.assertEqual(1, len(points))
+        self.assertEqual("h2o,a=a,b=b,c=c level=2i 1586048400000000000", points[0])