Fallback to other module data on get_energy_usage errors (#1245)

- The `get_energy_usage` query can fail if the device time is not set because the response includes the device time.
- Make `get_energy_usage` an optional query response so the energy module can fall back to getting the power from `get_emeter_data` or `get_current_power` on error.
- Devices on `energy_monitoring` version 1 still fail as they have no additional queries to fall back to.

tests/smart/modules/test_energy.py

@@ -1,7 +1,14 @@
+import copy
+import logging
+from contextlib import nullcontext as does_not_raise
+from unittest.mock import patch
+
 import pytest
 
-from kasa import Module, SmartDevice
+from kasa import DeviceError, Module
+from kasa.exceptions import SmartErrorCode
 from kasa.interfaces.energy import Energy
+from kasa.smart import SmartDevice
 from kasa.smart.modules import Energy as SmartEnergyModule
 from tests.conftest import has_emeter_smart
 
@@ -19,3 +26,84 @@ async def test_supported(dev: SmartDevice):
         assert energy_module.supports(Energy.ModuleFeature.VOLTAGE_CURRENT) is False
     else:
         assert energy_module.supports(Energy.ModuleFeature.VOLTAGE_CURRENT) is True
+
+
+@has_emeter_smart
+async def test_get_energy_usage_error(
+    dev: SmartDevice, caplog: pytest.LogCaptureFixture
+):
+    """Test errors on get_energy_usage."""
+    caplog.set_level(logging.DEBUG)
+
+    energy_module = dev.modules.get(Module.Energy)
+    if not energy_module:
+        pytest.skip(f"Energy module not supported for {dev}.")
+
+    version = dev._components["energy_monitoring"]
+
+    expected_raise = does_not_raise() if version > 1 else pytest.raises(DeviceError)
+    if version > 1:
+        expected = "get_energy_usage"
+        expected_current_consumption = 2.002
+    else:
+        expected = "current_power"
+        expected_current_consumption = None
+
+    assert expected in energy_module.data
+    assert energy_module.current_consumption is not None
+    assert energy_module.consumption_today is not None
+    assert energy_module.consumption_this_month is not None
+
+    last_update = copy.deepcopy(dev._last_update)
+    resp = copy.deepcopy(last_update)
+
+    if ed := resp.get("get_emeter_data"):
+        ed["power_mw"] = 2002
+    if cp := resp.get("get_current_power"):
+        cp["current_power"] = 2.002
+    resp["get_energy_usage"] = SmartErrorCode.JSON_DECODE_FAIL_ERROR
+
+    # version 1 only has get_energy_usage so module should raise an error if
+    # version 1 and get_energy_usage is in error
+    with patch.object(dev.protocol, "query", return_value=resp):
+        await dev.update()
+
+    with expected_raise:
+        assert "get_energy_usage" not in energy_module.data
+
+    assert energy_module.current_consumption == expected_current_consumption
+    assert energy_module.consumption_today is None
+    assert energy_module.consumption_this_month is None
+
+    msg = (
+        f"Removed key get_energy_usage from response for device {dev.host}"
+        " as it returned error: JSON_DECODE_FAIL_ERROR"
+    )
+    if version > 1:
+        assert msg in caplog.text
+
+    # Now test with no get_emeter_data
+    # This may not be valid scenario but we have a fallback to get_current_power
+    # just in case that should be tested.
+    caplog.clear()
+    resp = copy.deepcopy(last_update)
+
+    if cp := resp.get("get_current_power"):
+        cp["current_power"] = 2.002
+    resp["get_energy_usage"] = SmartErrorCode.JSON_DECODE_FAIL_ERROR
+
+    # Remove get_emeter_data from the response and from the device which will
+    # remember it otherwise.
+    resp.pop("get_emeter_data", None)
+    dev._last_update.pop("get_emeter_data", None)
+
+    with patch.object(dev.protocol, "query", return_value=resp):
+        await dev.update()
+
+    with expected_raise:
+        assert "get_energy_usage" not in energy_module.data
+
+    assert energy_module.current_consumption == expected_current_consumption
+
+    # message should only be logged once
+    assert msg not in caplog.text