Allow MockMicrogrid battery chains without meters

In most component graph configs, batteries would be attached to
inverters and the inverters would be meters.  But there might be some
cases where there are no meters,  and we'll have to read data from the
inverters.

This commit enables such test configs, that can be used in tests that
use the MockMicrogrid.

Signed-off-by: Sahas Subramanian <[email protected]>

Author: shsms

tests/timeseries/mock_microgrid.py

@@ -251,29 +251,23 @@ def add_chps(self, count: int) -> None:
             self._connections.add(Connection(self._connect_to, meter_id))
             self._connections.add(Connection(meter_id, chp_id))
 
-    def add_batteries(self, count: int) -> None:
+    def add_batteries(self, count: int, no_meter: bool = False) -> None:
         """Add batteries with connected inverters and meters to the microgrid.
 
         Args:
             count: number of battery sets to add.
+            no_meter: if True, do not add a meter for each battery set.
         """
         for _ in range(count):
             meter_id = self._id_increment * 10 + self.meter_id_suffix
             inv_id = self._id_increment * 10 + self.inverter_id_suffix
             bat_id = self._id_increment * 10 + self.battery_id_suffix
             self._id_increment += 1
 
-            self.meter_ids.append(meter_id)
             self.battery_inverter_ids.append(inv_id)
             self.battery_ids.append(bat_id)
             self.bat_inv_map[bat_id] = inv_id
 
-            self._components.add(
-                Component(
-                    meter_id,
-                    ComponentCategory.METER,
-                )
-            )
             self._components.add(
                 Component(inv_id, ComponentCategory.INVERTER, InverterType.BATTERY)
             )
@@ -285,9 +279,20 @@ def add_batteries(self, count: int) -> None:
             )
             self._start_battery_streaming(bat_id)
             self._start_inverter_streaming(inv_id)
-            self._start_meter_streaming(meter_id)
-            self._connections.add(Connection(self._connect_to, meter_id))
-            self._connections.add(Connection(meter_id, inv_id))
+
+            if no_meter:
+                self._connections.add(Connection(self._connect_to, inv_id))
+            else:
+                self.meter_ids.append(meter_id)
+                self._components.add(
+                    Component(
+                        meter_id,
+                        ComponentCategory.METER,
+                    )
+                )
+                self._start_meter_streaming(meter_id)
+                self._connections.add(Connection(self._connect_to, meter_id))
+                self._connections.add(Connection(meter_id, inv_id))
             self._connections.add(Connection(inv_id, bat_id))
 
     def add_solar_inverters(self, count: int) -> None: