Fix consumer_power() not working certain configurations.

RELEASE_NOTES.md

@@ -19,3 +19,6 @@
   component.
   So far we only had configurations like this: Meter -> Inverter -> PV. However
   the scenario with Inverter -> PV is also possible and now handled correctly.
+- Fix `consumer_power()` not working certain configurations.
+  In microgrids without consumers and no main meter, the formula
+  would never return any values.

benchmarks/timeseries/benchmark_datasourcing.py

@@ -70,7 +70,7 @@ async def benchmark_data_sourcing(
         num_ev_chargers * len(COMPONENT_METRIC_IDS) * num_msgs_per_battery
     )
     mock_grid = MockMicrogrid(
-        grid_side_meter=False, num_values=num_msgs_per_battery, sample_rate_s=0.0
+        grid_meter=False, num_values=num_msgs_per_battery, sample_rate_s=0.0
     )
 
     mock_grid.add_ev_chargers(num_ev_chargers)

src/frequenz/sdk/timeseries/_formula_engine/_formula_generators/_consumer_power_formula.py

@@ -5,14 +5,21 @@
 
 from __future__ import annotations
 
+import logging
 from collections import abc
 
 from ....microgrid import connection_manager
 from ....microgrid.component import Component, ComponentCategory, ComponentMetricId
 from ..._quantities import Power
 from .._formula_engine import FormulaEngine
 from .._resampled_formula_builder import ResampledFormulaBuilder
-from ._formula_generator import ComponentNotFound, FormulaGenerator
+from ._formula_generator import (
+    NON_EXISTING_COMPONENT_ID,
+    ComponentNotFound,
+    FormulaGenerator,
+)
+
+_logger = logging.getLogger(__name__)
 
 
 class ConsumerPowerFormula(FormulaGenerator[Power]):
@@ -121,4 +128,17 @@ def _gen_without_grid_meter(
             is_first = False
             builder.push_component_metric(successor.component_id, nones_are_zeros=False)
 
+        if len(builder.finalize()[0]) == 0:
+            # If there are no consumer components, we have to send 0 values at the same
+            # frequency as the other streams.  So we subscribe with a non-existing
+            # component id, just to get a `None` message at the resampling interval.
+            builder.push_component_metric(
+                NON_EXISTING_COMPONENT_ID, nones_are_zeros=True
+            )
+            _logger.warning(
+                "Unable to find any consumers in the component graph. "
+                "Subscribing to the resampling actor with a non-existing "
+                "component id, so that `0` values are sent from the formula."
+            )
+
         return builder.build()

tests/actor/test_battery_pool_status.py

@@ -30,7 +30,7 @@ async def test_batteries_status(self, mocker: MockerFixture) -> None:
         Args:
             mock_microgrid: mock microgrid client
         """
-        mock_microgrid = MockMicrogrid(grid_side_meter=True)
+        mock_microgrid = MockMicrogrid(grid_meter=True)
         mock_microgrid.add_batteries(3)
         await mock_microgrid.start(mocker)
 

tests/actor/test_battery_status.py

@@ -156,7 +156,7 @@ async def test_sync_update_status_with_messages(
         Args:
             mock_microgrid: mock_microgrid fixture
         """
-        mock_microgrid = MockMicrogrid(grid_side_meter=True)
+        mock_microgrid = MockMicrogrid(grid_meter=True)
         mock_microgrid.add_batteries(3)
         await mock_microgrid.start(mocker)
 
@@ -318,7 +318,7 @@ async def test_sync_blocking_feature(self, mocker: MockerFixture) -> None:
         Args:
             mock_microgrid: mock_microgrid fixture
         """
-        mock_microgrid = MockMicrogrid(grid_side_meter=True)
+        mock_microgrid = MockMicrogrid(grid_meter=True)
         mock_microgrid.add_batteries(3)
         await mock_microgrid.start(mocker)
 
@@ -435,7 +435,7 @@ async def test_sync_blocking_interrupted_with_with_max_data(
         Args:
             mock_microgrid: mock_microgrid fixture
         """
-        mock_microgrid = MockMicrogrid(grid_side_meter=True)
+        mock_microgrid = MockMicrogrid(grid_meter=True)
         mock_microgrid.add_batteries(3)
         await mock_microgrid.start(mocker)
 
@@ -486,7 +486,7 @@ async def test_sync_blocking_interrupted_with_invalid_message(
         Args:
             mock_microgrid: mock_microgrid fixture
         """
-        mock_microgrid = MockMicrogrid(grid_side_meter=True)
+        mock_microgrid = MockMicrogrid(grid_meter=True)
         mock_microgrid.add_batteries(3)
         await mock_microgrid.start(mocker)
 
@@ -547,7 +547,7 @@ async def test_timers(self, mocker: MockerFixture) -> None:
             mock_microgrid: mock_microgrid fixture
             mocker: pytest mocker instance
         """
-        mock_microgrid = MockMicrogrid(grid_side_meter=True)
+        mock_microgrid = MockMicrogrid(grid_meter=True)
         mock_microgrid.add_batteries(3)
         await mock_microgrid.start(mocker)
 
@@ -609,7 +609,7 @@ async def test_async_battery_status(self, mocker: MockerFixture) -> None:
         Args:
             mock_microgrid: mock_microgrid fixture
         """
-        mock_microgrid = MockMicrogrid(grid_side_meter=True)
+        mock_microgrid = MockMicrogrid(grid_meter=True)
         mock_microgrid.add_batteries(3)
         await mock_microgrid.start(mocker)
 
@@ -690,7 +690,7 @@ async def setup_tracker(
         self, mocker: MockerFixture
     ) -> AsyncIterator[tuple[MockMicrogrid, Receiver[Status]]]:
         """Setup a BatteryStatusTracker instance to run tests with."""
-        mock_microgrid = MockMicrogrid(grid_side_meter=True)
+        mock_microgrid = MockMicrogrid(grid_meter=True)
         mock_microgrid.add_batteries(1)
         await mock_microgrid.start(mocker)
 

tests/actor/test_power_distributing.py

@@ -47,7 +47,7 @@ class TestPowerDistributingActor:
 
     async def test_constructor(self, mocker: MockerFixture) -> None:
         """Test if gets all necessary data."""
-        mockgrid = MockMicrogrid(grid_side_meter=True)
+        mockgrid = MockMicrogrid(grid_meter=True)
         mockgrid.add_batteries(2)
         mockgrid.add_batteries(1, no_meter=True)
         await mockgrid.start(mocker)
@@ -68,7 +68,7 @@ async def test_constructor(self, mocker: MockerFixture) -> None:
         await mockgrid.cleanup()
 
         # Test if it works without grid side meter
-        mockgrid = MockMicrogrid(grid_side_meter=False)
+        mockgrid = MockMicrogrid(grid_meter=False)
         mockgrid.add_batteries(1)
         mockgrid.add_batteries(2, no_meter=True)
         await mockgrid.start(mocker)
@@ -108,7 +108,7 @@ async def init_component_data(self, mockgrid: MockMicrogrid) -> None:
 
     async def test_power_distributor_one_user(self, mocker: MockerFixture) -> None:
         """Test if power distribution works with single user works."""
-        mockgrid = MockMicrogrid(grid_side_meter=False)
+        mockgrid = MockMicrogrid(grid_meter=False)
         mockgrid.add_batteries(3)
         await mockgrid.start(mocker)
         await self.init_component_data(mockgrid)
@@ -157,7 +157,7 @@ async def test_power_distributor_one_user(self, mocker: MockerFixture) -> None:
 
     async def test_battery_soc_nan(self, mocker: MockerFixture) -> None:
         """Test if battery with SoC==NaN is not used."""
-        mockgrid = MockMicrogrid(grid_side_meter=False)
+        mockgrid = MockMicrogrid(grid_meter=False)
         mockgrid.add_batteries(3)
         await mockgrid.start(mocker)
         await self.init_component_data(mockgrid)
@@ -222,7 +222,7 @@ async def test_battery_soc_nan(self, mocker: MockerFixture) -> None:
 
     async def test_battery_capacity_nan(self, mocker: MockerFixture) -> None:
         """Test battery with capacity set to NaN is not used."""
-        mockgrid = MockMicrogrid(grid_side_meter=False)
+        mockgrid = MockMicrogrid(grid_meter=False)
         mockgrid.add_batteries(3)
         await mockgrid.start(mocker)
         await self.init_component_data(mockgrid)
@@ -280,7 +280,7 @@ async def test_battery_capacity_nan(self, mocker: MockerFixture) -> None:
 
     async def test_battery_power_bounds_nan(self, mocker: MockerFixture) -> None:
         """Test battery with power bounds set to NaN is not used."""
-        mockgrid = MockMicrogrid(grid_side_meter=False)
+        mockgrid = MockMicrogrid(grid_meter=False)
         mockgrid.add_batteries(3)
         await mockgrid.start(mocker)
         await self.init_component_data(mockgrid)
@@ -356,7 +356,7 @@ async def test_power_distributor_invalid_battery_id(
         self, mocker: MockerFixture
     ) -> None:
         """Test if power distribution raises error if any battery id is invalid."""
-        mockgrid = MockMicrogrid(grid_side_meter=False)
+        mockgrid = MockMicrogrid(grid_meter=False)
         mockgrid.add_batteries(3)
         await mockgrid.start(mocker)
         await self.init_component_data(mockgrid)
@@ -404,7 +404,7 @@ async def test_power_distributor_one_user_adjust_power_consume(
         self, mocker: MockerFixture
     ) -> None:
         """Test if power distribution works with single user works."""
-        mockgrid = MockMicrogrid(grid_side_meter=False)
+        mockgrid = MockMicrogrid(grid_meter=False)
         mockgrid.add_batteries(3)
         await mockgrid.start(mocker)
         await self.init_component_data(mockgrid)
@@ -457,7 +457,7 @@ async def test_power_distributor_one_user_adjust_power_supply(
         self, mocker: MockerFixture
     ) -> None:
         """Test if power distribution works with single user works."""
-        mockgrid = MockMicrogrid(grid_side_meter=False)
+        mockgrid = MockMicrogrid(grid_meter=False)
         mockgrid.add_batteries(3)
         await mockgrid.start(mocker)
         await self.init_component_data(mockgrid)
@@ -510,7 +510,7 @@ async def test_power_distributor_one_user_adjust_power_success(
         self, mocker: MockerFixture
     ) -> None:
         """Test if power distribution works with single user works."""
-        mockgrid = MockMicrogrid(grid_side_meter=False)
+        mockgrid = MockMicrogrid(grid_meter=False)
         mockgrid.add_batteries(3)
         await mockgrid.start(mocker)
         await self.init_component_data(mockgrid)
@@ -561,7 +561,7 @@ async def test_power_distributor_one_user_adjust_power_success(
 
     async def test_not_all_batteries_are_working(self, mocker: MockerFixture) -> None:
         """Test if power distribution works if not all batteries are working."""
-        mockgrid = MockMicrogrid(grid_side_meter=False)
+        mockgrid = MockMicrogrid(grid_meter=False)
         mockgrid.add_batteries(3)
         await mockgrid.start(mocker)
         await self.init_component_data(mockgrid)
@@ -615,7 +615,7 @@ async def test_use_all_batteries_none_is_working(
         self, mocker: MockerFixture
     ) -> None:
         """Test all batteries are used if none of them works."""
-        mockgrid = MockMicrogrid(grid_side_meter=False)
+        mockgrid = MockMicrogrid(grid_meter=False)
         mockgrid.add_batteries(3)
         await mockgrid.start(mocker)
         await self.init_component_data(mockgrid)
@@ -668,7 +668,7 @@ async def test_force_request_a_battery_is_not_working(
         self, mocker: MockerFixture
     ) -> None:
         """Test force request when a battery is not working."""
-        mockgrid = MockMicrogrid(grid_side_meter=False)
+        mockgrid = MockMicrogrid(grid_meter=False)
         mockgrid.add_batteries(3)
         await mockgrid.start(mocker)
         await self.init_component_data(mockgrid)
@@ -724,7 +724,7 @@ async def test_force_request_battery_nan_value_non_cached(
     ) -> None:
         """Test battery with NaN in SoC, capacity or power is used if request is forced."""
         # pylint: disable=too-many-locals
-        mockgrid = MockMicrogrid(grid_side_meter=False)
+        mockgrid = MockMicrogrid(grid_meter=False)
         mockgrid.add_batteries(3)
         await mockgrid.start(mocker)
         await self.init_component_data(mockgrid)
@@ -797,7 +797,7 @@ async def test_force_request_batteries_nan_values_cached(
         self, mocker: MockerFixture
     ) -> None:
         """Test battery with NaN in SoC, capacity or power is used if request is forced."""
-        mockgrid = MockMicrogrid(grid_side_meter=False)
+        mockgrid = MockMicrogrid(grid_meter=False)
         mockgrid.add_batteries(3)
         await mockgrid.start(mocker)
         await self.init_component_data(mockgrid)

tests/timeseries/_battery_pool/test_battery_pool.py

@@ -461,7 +461,7 @@ async def run_test_battery_status_channel(  # pylint: disable=too-many-arguments
 
 async def test_battery_pool_power(mocker: MockerFixture) -> None:
     """Test `BatteryPool.{,production,consumption}_power` methods."""
-    mockgrid = MockMicrogrid(grid_side_meter=True)
+    mockgrid = MockMicrogrid(grid_meter=True)
     mockgrid.add_batteries(2)
     await mockgrid.start(mocker)
 

tests/timeseries/_formula_engine/test_formula_composition.py

@@ -25,16 +25,17 @@ async def test_formula_composition(  # pylint: disable=too-many-locals
         mocker: MockerFixture,
     ) -> None:
         """Test the composition of formulas."""
-        mockgrid = MockMicrogrid(grid_side_meter=False)
+        mockgrid = MockMicrogrid(grid_meter=False)
+        mockgrid.add_consumer_meters()
         mockgrid.add_batteries(3)
         mockgrid.add_solar_inverters(2)
         await mockgrid.start(mocker)
 
         logical_meter = microgrid.logical_meter()
         battery_pool = microgrid.battery_pool()
-        main_meter_recv = get_resampled_stream(
+        grid_meter_recv = get_resampled_stream(
             logical_meter._namespace,  # pylint: disable=protected-access
-            4,
+            mockgrid.meter_ids[0],
             ComponentMetricId.ACTIVE_POWER,
             Power.from_watts,
         )
@@ -53,7 +54,7 @@ async def test_formula_composition(  # pylint: disable=too-many-locals
         grid_pow = await grid_power_recv.receive()
         pv_pow = await pv_power_recv.receive()
         bat_pow = await battery_power_recv.receive()
-        main_pow = await main_meter_recv.receive()
+        main_pow = await grid_meter_recv.receive()
         inv_calc_pow = await inv_calc_recv.receive()
 
         assert (
@@ -98,7 +99,7 @@ async def test_formula_composition(  # pylint: disable=too-many-locals
 
     async def test_formula_composition_missing_pv(self, mocker: MockerFixture) -> None:
         """Test the composition of formulas with missing PV power data."""
-        mockgrid = MockMicrogrid(grid_side_meter=False)
+        mockgrid = MockMicrogrid(grid_meter=False)
         mockgrid.add_batteries(3)
         await mockgrid.start(mocker)
         battery_pool = microgrid.battery_pool()
@@ -136,7 +137,7 @@ async def test_formula_composition_missing_pv(self, mocker: MockerFixture) -> No
 
     async def test_formula_composition_missing_bat(self, mocker: MockerFixture) -> None:
         """Test the composition of formulas with missing battery power data."""
-        mockgrid = MockMicrogrid(grid_side_meter=False)
+        mockgrid = MockMicrogrid(grid_meter=False)
         mockgrid.add_solar_inverters(2)
         await mockgrid.start(mocker)
         battery_pool = microgrid.battery_pool()
@@ -149,9 +150,7 @@ async def test_formula_composition_missing_bat(self, mocker: MockerFixture) -> N
 
         count = 0
         for _ in range(10):
-            await mockgrid.mock_resampler.send_meter_power(
-                [10.0 + count, 12.0 + count, 14.0 + count]
-            )
+            await mockgrid.mock_resampler.send_meter_power([12.0 + count, 14.0 + count])
             await mockgrid.mock_resampler.send_non_existing_component_value()
             bat_pow = await battery_power_recv.receive()
             pv_pow = await pv_power_recv.receive()
@@ -173,7 +172,7 @@ async def test_formula_composition_missing_bat(self, mocker: MockerFixture) -> N
 
     async def test_formula_composition_constant(self, mocker: MockerFixture) -> None:
         """Test the composition of formulas with constant values."""
-        mockgrid = MockMicrogrid(grid_side_meter=True)
+        mockgrid = MockMicrogrid(grid_meter=True)
         await mockgrid.start(mocker)
 
         logical_meter = microgrid.logical_meter()
@@ -243,9 +242,7 @@ async def test_formula_composition_constant(self, mocker: MockerFixture) -> None
 
     async def test_3_phase_formulas(self, mocker: MockerFixture) -> None:
         """Test 3 phase formulas current formulas and their composition."""
-        mockgrid = MockMicrogrid(
-            grid_side_meter=False, sample_rate_s=0.05, num_namespaces=2
-        )
+        mockgrid = MockMicrogrid(grid_meter=False, sample_rate_s=0.05, num_namespaces=2)
         mockgrid.add_batteries(3)
         mockgrid.add_ev_chargers(1)
         await mockgrid.start(mocker)
@@ -266,7 +263,6 @@ async def test_3_phase_formulas(self, mocker: MockerFixture) -> None:
                     [10.0, 12.0, 14.0],
                     [10.0, 12.0, 14.0],
                     [10.0, 12.0, 14.0],
-                    [10.0, 12.0, 14.0],
                 ]
             )
             await mockgrid.mock_resampler.send_evc_current(