refactor(config): key microgrids by int

Normalize microgrid map keys to plain integers, matching metadata
and relation IDs. Keep string keys only at TOML and serialization
boundaries.

Signed-off-by: cwasicki <126617870+cwasicki@users.noreply.github.com>

Author: cwasicki

RELEASE_NOTES.md

@@ -45,6 +45,14 @@
 - The implementation modules `config.load` and `config.microgrid` are now
   private. Import their public names from `frequenz.gridpool.config` instead.
 
+- Microgrids are now keyed by `int` microgrid ID, not `str`. This covers
+  `AssetsConfig.microgrids`, including documents returned by `load_configs`.
+  Index the mapping by integer ID:
+
+  ```python
+  configs[1]  # was configs["1"]
+  ```
+
 ## New Features
 
 - `AssetsConfig` gives the `assets` namespace a type, so the entities still to

src/frequenz/gridpool/cli/__main__.py

@@ -203,9 +203,7 @@ async def generate_config(
     ids = list(dict.fromkeys(microgrid_ids)) or None
     if inplace and ids is None:
         assert default_file is not None
-        ids = sorted(
-            int(mid) for mid in AssetsConfig.load_from_files(default_file).microgrids
-        )
+        ids = sorted(AssetsConfig.load_from_files(default_file).microgrids)
 
     async with AssetsApiClient(url, auth_key=key, sign_secret=secret) as client:
         if inplace:

src/frequenz/gridpool/cli/_dump_config.py

@@ -71,22 +71,22 @@ def _iter_leaves(
     return leaves
 
 
-def dump_map(configs: dict[str, MicrogridConfig]) -> str:
+def dump_map(configs: dict[int, MicrogridConfig]) -> str:
     """Serialize a mapping of microgrid configs to dotted-key TOML.
 
     Args:
-        configs: Mapping from microgrid ID (as string) to `MicrogridConfig`.
+        configs: Mapping from microgrid ID to `MicrogridConfig`.
 
     Returns:
         The TOML representation as a string, with one blank line between
         microgrids and entries sorted by numeric microgrid ID.
     """
     schema = MicrogridConfig.Schema()
     doc = tomlkit.document()
-    for mid in sorted(configs, key=int):
+    for mid in sorted(configs):
         dumped = schema.dump(configs[mid])
         assert isinstance(dumped, dict)
-        leaves = _iter_leaves([mid], dumped)
+        leaves = _iter_leaves([str(mid)], dumped)
         if not leaves:
             continue
         if doc.body:

src/frequenz/gridpool/cli/_patch_config.py

@@ -20,25 +20,25 @@
 from ._dump_config import _format_value, _iter_leaves
 
 
-def patch_file(path: Path, configs: dict[str, MicrogridConfig]) -> str:
+def patch_file(path: Path, configs: dict[int, MicrogridConfig]) -> str:
     """Patch the TOML file at `path` with any leaves missing from `configs`.
 
     Args:
         path: Path to the existing TOML file to patch.
-        configs: Mapping from microgrid ID (as string) to `MicrogridConfig`.
+        configs: Mapping from microgrid ID to `MicrogridConfig`.
 
     Returns:
         The patched TOML text; the caller is responsible for writing it back.
     """
     return patch_text(path.read_text(), configs)
 
 
-def patch_text(original: str, configs: dict[str, MicrogridConfig]) -> str:
+def patch_text(original: str, configs: dict[int, MicrogridConfig]) -> str:
     """Patch dotted-key TOML text with any leaves missing from `configs`.
 
     Args:
         original: The existing TOML text to patch.
-        configs: Mapping from microgrid ID (as string) to `MicrogridConfig`.
+        configs: Mapping from microgrid ID to `MicrogridConfig`.
 
     Returns:
         The patched TOML text.
@@ -51,7 +51,8 @@ def patch_text(original: str, configs: dict[str, MicrogridConfig]) -> str:
     # into the rendered text instead.
     orphans: dict[str, list[tuple[list[str], Any]]] = {}
 
-    for mid, cfg in configs.items():
+    for microgrid_id, cfg in configs.items():
+        mid = str(microgrid_id)
         dumped = schema.dump(cfg)
         assert isinstance(dumped, dict)
         leaves = _iter_leaves([], dumped)

src/frequenz/gridpool/config/_assets.py

@@ -82,7 +82,7 @@ def _merge_file_tables(
 class AssetsConfig:
     """Entities described by a config document, keyed by their ID."""
 
-    microgrids: dict[str, MicrogridConfig] = field(default_factory=dict)
+    microgrids: dict[int, MicrogridConfig] = field(default_factory=dict)
     """Microgrids, keyed by microgrid ID."""
 
     market_locations: dict[str, MarketLocationConfig] = field(default_factory=dict)
@@ -115,9 +115,7 @@ def __post_init__(self) -> None:
             ValueError: If a key is not the ID of the entry it holds.
         """
         for mid, cfg in self.microgrids.items():
-            if not mid.isdigit():
-                raise ValueError(f"Microgrid ID key must be numeric, got {mid}")
-            if int(cfg.meta.microgrid_id) != int(mid):
+            if int(cfg.meta.microgrid_id) != mid:
                 raise ValueError(
                     f"Microgrid ID mismatch: key {mid} != {cfg.meta.microgrid_id}"
                 )

src/frequenz/gridpool/config/_load.py

@@ -126,7 +126,9 @@ async def load_configs(
         )
         schema = MicrogridConfig.Schema()
         api_table: dict[str, Any] = {
-            "microgrids": {mid: schema.dump(cfg) for mid, cfg in assets_configs.items()}
+            "microgrids": {
+                str(mid): schema.dump(cfg) for mid, cfg in assets_configs.items()
+            }
         }
         merged = _deep_merge(merged, api_table)
 
@@ -142,7 +144,7 @@ async def _load_microgrids_from_api(
     assets_client: AssetsApiClient,
     microgrid_ids: list[int],
     component_graph_config: ComponentGraphConfig | None = None,
-) -> dict[str, "MicrogridConfig"]:
+) -> dict[int, "MicrogridConfig"]:
     """Load microgrid configs from the Assets API.
 
     For each microgrid, fetches its location metadata (latitude, longitude) and
@@ -165,14 +167,13 @@ async def _load_microgrids_from_api(
             `ComponentGraphConfig`.  Defaults to that class's own defaults.
 
     Returns:
-        dict[str, MicrogridConfig]:
-            Mapping from microgrid ID (as string) to the loaded
-            `MicrogridConfig` instance. Microgrids whose metadata could not be
-            loaded are omitted, so the returned mapping may cover fewer
-            microgrids than were requested.
+        dict[int, MicrogridConfig]:
+            Mapping from microgrid ID to the loaded `MicrogridConfig` instance.
+            Microgrids whose metadata could not be loaded are omitted, so the
+            returned mapping may cover fewer microgrids than were requested.
     """
     generator = ComponentGraphGenerator(assets_client, config=component_graph_config)
-    configs: dict[str, MicrogridConfig] = {}
+    configs: dict[int, MicrogridConfig] = {}
     for microgrid_id in microgrid_ids:
         try:
             cfg = await _build_config_from_metadata(assets_client, microgrid_id)
@@ -195,7 +196,7 @@ async def _load_microgrids_from_api(
                 exc,
             )
 
-        configs[str(microgrid_id)] = cfg
+        configs[microgrid_id] = cfg
 
     return configs
 

src/frequenz/gridpool/config/_microgrid.py

@@ -291,7 +291,7 @@ def formula(self, component_type: str, metric: str) -> str:
     Schema: ClassVar[Type[Schema]] = Schema
 
     @classmethod
-    def _load_table_entries(cls, data: dict[str, Any]) -> dict[str, Self]:
+    def _load_table_entries(cls, data: dict[str, Any]) -> dict[int, Self]:
         """Load microgrid configurations from table entries.
 
         Args:
@@ -327,6 +327,6 @@ def _load_table_entries(cls, data: dict[str, Any]) -> dict[str, Self]:
                     f"Table reader: Microgrid ID mismatch: key {mid} != {mgrid.meta.microgrid_id}"
                 )
 
-            mgrids[mid] = mgrid
+            mgrids[int(mid)] = mgrid
 
         return mgrids

tests/test_config.py

@@ -48,7 +48,7 @@
 def valid_microgrid_config() -> MicrogridConfig:
     """Fixture to provide a valid MicrogridConfig instance."""
     # pylint: disable=protected-access
-    return MicrogridConfig._load_table_entries(VALID_CONFIG)["1"]
+    return MicrogridConfig._load_table_entries(VALID_CONFIG)[1]
 
 
 def test_is_valid_type() -> None:
@@ -136,17 +136,17 @@ def test_load_configs(mocker: MockerFixture) -> None:
     mocker.patch("pathlib.Path.is_file", mocker.Mock(return_value=True))
     configs = AssetsConfig.load_from_files(Path("mock_path.toml")).microgrids
 
-    assert "1" in configs
-    assert configs["1"].meta is not None
-    assert configs["1"].meta.name == "Test Grid"
+    assert 1 in configs
+    assert configs[1].meta is not None
+    assert configs[1].meta.name == "Test Grid"
 
-    pv_config = configs["1"].pv
+    pv_config = configs[1].pv
     assert pv_config is not None
     pv_system = pv_config.get("PV1")
     assert pv_system is not None
     assert pv_system.peak_power == 5000
 
-    battery_config = configs["1"].battery
+    battery_config = configs[1].battery
     assert battery_config is not None
     battery_system = battery_config.get("BAT1")
     assert battery_system is not None
@@ -194,8 +194,8 @@ def test_load_prefixed(tmp_path: Path, caplog: pytest.LogCaptureFixture) -> None
         _write(tmp_path, "prefixed.toml", _PREFIXED_TOML)
     ).microgrids
 
-    assert configs["1"].meta.name == "Test Grid"
-    assert configs["1"].component_type_ids("pv") == [101, 102]
+    assert configs[1].meta.name == "Test Grid"
+    assert configs[1].component_type_ids("pv") == [101, 102]
     assert "deprecated" not in caplog.text
 
 
@@ -206,7 +206,7 @@ def test_load_legacy_warns(tmp_path: Path, caplog: pytest.LogCaptureFixture) ->
     with caplog.at_level(logging.WARNING):
         configs = AssetsConfig.load_from_files(path).microgrids
 
-    assert configs["1"].meta.name == "Test Grid"
+    assert configs[1].meta.name == "Test Grid"
     assert "deprecated" in caplog.text
     assert str(path) in caplog.text
 
@@ -241,8 +241,8 @@ async def test_merge_prefixed_base_with_legacy_override(tmp_path: Path) -> None:
         await load_configs(default_files=base, override_files=override)
     ).microgrids
 
-    assert configs["1"].meta.name == "Renamed"
-    assert configs["1"].component_type_ids("pv") == [101, 102]
+    assert configs[1].meta.name == "Renamed"
+    assert configs[1].component_type_ids("pv") == [101, 102]
 
 
 def test_load_from_files_layers_fields(tmp_path: Path) -> None:
@@ -257,8 +257,8 @@ def test_load_from_files_layers_fields(tmp_path: Path) -> None:
 
     configs = AssetsConfig.load_from_files([base, override]).microgrids
 
-    assert configs["1"].meta.name == "Renamed"
-    assert configs["1"].component_type_ids("pv") == [101, 102]
+    assert configs[1].meta.name == "Renamed"
+    assert configs[1].component_type_ids("pv") == [101, 102]
 
 
 def test_assets_config_rejects_mismatched_id() -> None:
@@ -292,5 +292,5 @@ def test_assets_config_warns_on_unknown_entities(
     with caplog.at_level(logging.WARNING):
         config = AssetsConfig.load_from_files(path)
 
-    assert sorted(config.microgrids) == ["1"]
+    assert sorted(config.microgrids) == [1]
     assert "gridpool" in caplog.text

tests/test_dump_config.py

@@ -17,7 +17,7 @@
 def test_dump_map_round_trips() -> None:
     """A serialized config parses back to the same dotted-key structure."""
     configs = {
-        "10": MicrogridConfig(
+        10: MicrogridConfig(
             meta=Metadata(microgrid_id=10, name="Demo", latitude=52.5),
             ctype={
                 "pv": ComponentTypeConfig(meter=[2], formula={"AC_POWER_ACTIVE": "#2"}),
@@ -36,7 +36,7 @@ def test_dump_map_round_trips() -> None:
 
 def test_dump_map_omits_empty_and_none() -> None:
     """Empty and None fields are dropped from the output."""
-    configs = {"7": MicrogridConfig(meta=Metadata(microgrid_id=7))}
+    configs = {7: MicrogridConfig(meta=Metadata(microgrid_id=7))}
 
     text = dump_map(configs)
 
@@ -51,7 +51,7 @@ def test_dump_map_empty() -> None:
 def test_dump_map_renders_whole_floats_as_underscored_ints() -> None:
     """Whole-number float fields (e.g. peak/rated power) render as `1_736_680`, not `1736680.0`."""
     configs = {
-        "10": MicrogridConfig(
+        10: MicrogridConfig(
             meta=Metadata(microgrid_id=10, latitude=52.5),
             pv={"1": PVConfig(peak_power=1_736_680.0, rated_power=1_400_000.0)},
         )

tests/test_load.py

@@ -69,7 +69,7 @@ async def test_load_microgrids_from_api_derives_formulas_and_ids() -> None:
     """A config loaded from the API gets both formulas and component IDs."""
     configs = await _load_microgrids_from_api(_mock_client(), [10])
 
-    cfg = configs["10"]
+    cfg = configs[10]
     assert cfg.ctype["pv"].formula == {"AC_POWER_ACTIVE": "COALESCE(#4, #2, 0.0)"}
     assert cfg.ctype["pv"].inverter == [4]
     assert cfg.ctype["pv"].meter == [2]
@@ -89,7 +89,7 @@ async def test_load_microgrids_from_api_honours_the_component_graph_config() ->
     )
 
     # Meter first, the opposite of the default order asserted above.
-    ctype = configs["10"].ctype
+    ctype = configs[10].ctype
     assert ctype["pv"].formula == {"AC_POWER_ACTIVE": "COALESCE(#2, #4, 0.0)"}
 
 
@@ -105,7 +105,7 @@ async def test_load_configs_forwards_the_component_graph_config() -> None:
         )
     ).microgrids
 
-    assert configs["10"].ctype["pv"].formula == {
+    assert configs[10].ctype["pv"].formula == {
         "AC_POWER_ACTIVE": "COALESCE(#2, #4, 0.0)"
     }
 
@@ -128,7 +128,7 @@ async def test_load_microgrids_from_api_keeps_metadata_when_graph_fails() -> Non
 
     configs = await _load_microgrids_from_api(client, [10])
 
-    cfg = configs["10"]
+    cfg = configs[10]
     assert cfg.meta.microgrid_id == 10
     assert cfg.ctype == {}
 
@@ -149,7 +149,7 @@ async def test_load_configs_validates_the_merged_whole(tmp_path: Path) -> None:
 
     document = await load_configs(default_files=default, override_files=override)
 
-    assert document.microgrids["1"].meta.name == "Override"
+    assert document.microgrids[1].meta.name == "Override"
 
 
 async def test_load_configs_returns_the_whole_document(tmp_path: Path) -> None:
@@ -161,6 +161,7 @@ async def test_load_configs_returns_the_whole_document(tmp_path: Path) -> None:
     default = tmp_path / "default.toml"
     default.write_text(
         "assets.microgrids.10.meta.microgrid_id = 10\n"
+        'assets.microgrids.10.meta.name = "File name"\n'
         'assets.market_locations.51171875559.id = "51171875559"\n'
         "assets.relations.M10L51171875559.microgrid_id = 10\n"
         'assets.relations.M10L51171875559.market_location_id = "51171875559"\n'
@@ -169,7 +170,8 @@ async def test_load_configs_returns_the_whole_document(tmp_path: Path) -> None:
     document = await load_configs(default_files=default, assets_client=_mock_client())
 
     # The API layer filled the microgrid's component config.
-    assert document.microgrids["10"].ctype
+    assert document.microgrids[10].ctype
+    assert document.microgrids[10].meta.name == "File name"
     # The file's topology survived the merge with the API layer.
     assert "M10L51171875559" in document.relations
     assert "51171875559" in document.market_locations