consumer fix generic JSON consumer

packages/modules/consumers/generic/json/consumer.py

@@ -67,7 +67,9 @@ def update() -> ConsumerState:
             currents=currents,
             imported=imported,
             exported=exported,
-            temperatures=temperatures if isinstance(temperatures, list) else [temperatures],
+            temperatures=(temperatures if isinstance(temperatures, list)
+                          else [temperatures] if temperatures is not None
+                          else None),
         )
 
     def switch_on():

packages/modules/consumers/generic/json/consumer_test.py

@@ -0,0 +1,38 @@
+from unittest.mock import Mock
+
+import requests_mock
+
+from modules.common import configurable_consumer
+from modules.consumers.generic.json.config import Json, JsonConfiguration
+from modules.consumers.generic.json.consumer import create_consumer
+
+SAMPLE_URL = "http://1.1.1.1/status"
+
+
+def _create_consumer(monkeypatch, **configuration_kwargs):
+    # ConfigurableConsumer.__init__ needs a store, uninteresting for these tests
+    monkeypatch.setattr(configurable_consumer, "get_component_value_store", Mock())
+    config = Json(configuration=JsonConfiguration(
+        url=SAMPLE_URL, jq_power=".power", **configuration_kwargs))
+    return create_consumer(config)
+
+
+def test_temperatures_is_none_when_jq_temperatures_not_configured(monkeypatch, requests_mock: requests_mock.Mocker):
+    # discussion #3466, discussioncomment-19500817: without jq_temperatures, temperatures must stay
+    # None, not [None] - setdata.py rejects a list containing None as an invalid payload
+    requests_mock.get(SAMPLE_URL, json={"power": 123})
+    consumer = _create_consumer(monkeypatch)
+
+    state = consumer.module_updater()
+
+    assert state.temperatures is None
+
+
+def test_temperatures_is_wrapped_in_list_when_jq_temperatures_configured(
+        monkeypatch, requests_mock: requests_mock.Mocker):
+    requests_mock.get(SAMPLE_URL, json={"power": 123, "temp": 42.5})
+    consumer = _create_consumer(monkeypatch, jq_temperatures=".temp")
+
+    state = consumer.module_updater()
+
+    assert state.temperatures == [42.5]