Add directory option microgrid config

RELEASE_NOTES.md

@@ -14,4 +14,6 @@
 
 ## Bug Fixes
 
-<!-- Here goes notable bug fixes that are worth a special mention or explanation -->
+- `load_configs()` and `load_configs_from_files()` now accept directory paths in
+  addition to individual TOML files. When a directory is provided, all
+  `*.toml` files in that directory are loaded in sorted order.

src/frequenz/gridpool/config/__init__.py

@@ -5,11 +5,7 @@
 
 from frequenz.microgrid_component_graph import ComponentGraphConfig, FormulaOverrides
 
-from .load import (
-    load_configs,
-    load_configs_from_api,
-    load_configs_from_files,
-)
+from .load import load_configs, load_configs_from_api, load_configs_from_files
 from .microgrid import (
     BatteryConfig,
     ComponentCategory,

src/frequenz/gridpool/config/load.py

@@ -24,12 +24,7 @@
     pv_inverter_ids,
     pv_meter_ids,
 )
-from .microgrid import (
-    ComponentTypeConfig,
-    Metadata,
-    MicrogridConfig,
-    merge_config_maps,
-)
+from .microgrid import ComponentTypeConfig, Metadata, MicrogridConfig, merge_config_maps
 
 _logger = logging.getLogger(__name__)
 
@@ -123,16 +118,20 @@ async def load_configs(
     return merge_config_maps(base=configs, override=override_configs)
 
 
+# pylint: disable=too-many-branches
 def load_configs_from_files(
     microgrid_config_files: str | Path | list[str | Path] | None = None,
 ) -> dict[str, "MicrogridConfig"]:
-    """Load multiple microgrid configurations from one or more files.
+    """Load multiple microgrid configurations from one or more paths/files.
 
     Configs for a single microgrid are expected to be in a single file.
     Later files with the same microgrid ID will overwrite the previous configs.
+    Directory paths are expanded to all `.toml` files they contain.
 
     Args:
-        microgrid_config_files: Path to a single microgrid config file or list of paths.
+        microgrid_config_files:
+            Path to a single microgrid config file or directory, or a list of
+            file and directory paths.
 
     Returns:
         Dictionary of single microgrid formula configs with microgrid IDs as keys.
@@ -148,12 +147,18 @@ def load_configs_from_files(
     config_files: list[Path] = []
 
     if microgrid_config_files:
-        if isinstance(microgrid_config_files, str):
-            config_files = [Path(microgrid_config_files)]
-        elif isinstance(microgrid_config_files, Path):
-            config_files = [microgrid_config_files]
-        elif isinstance(microgrid_config_files, list):
-            config_files = [Path(f) for f in microgrid_config_files]
+        # normalize to a list of items
+        if isinstance(microgrid_config_files, (str, Path)):
+            paths = [microgrid_config_files]
+        else:
+            paths = microgrid_config_files
+
+        for item in paths:
+            config_path = Path(item)
+            if config_path.is_dir():
+                config_files.extend(sorted(config_path.glob("*.toml")))
+            else:
+                config_files.append(config_path)
 
     if len(config_files) == 0:
         raise ValueError(

tests/test_config.py

@@ -147,6 +147,37 @@ def test_load_configs(mocker: MockerFixture) -> None:
     assert battery_system.capacity == 10000
 
 
+def test_load_configs_from_directory(tmp_path: Path) -> None:
+    """Loading from a directory picks up its TOML files."""
+    config_dir = tmp_path / "configs"
+    config_dir.mkdir()
+    (config_dir / "mg-1.toml").write_text(
+        """
+        1.meta.microgrid_id = 1
+        1.meta.name = "Test Grid 1"
+        1.meta.gid = 1
+        """,
+        encoding="utf-8",
+    )
+    (config_dir / "mg-2.toml").write_text(
+        """
+        2.meta.microgrid_id = 2
+        2.meta.name = "Test Grid 2"
+        2.meta.gid = 2
+        """,
+        encoding="utf-8",
+    )
+    (config_dir / "ignore.txt").write_text("not toml", encoding="utf-8")
+
+    configs = load_configs_from_files(config_dir)
+
+    assert set(configs) == {"1", "2"}
+    assert configs["1"].meta is not None
+    assert configs["1"].meta.name == "Test Grid 1"
+    assert configs["2"].meta is not None
+    assert configs["2"].meta.name == "Test Grid 2"
+
+
 def _assert_optional_field(value: float | None, expected: float) -> None:
     """Validate an optional field.
 

tests/test_load.py

@@ -3,6 +3,7 @@
 
 """Tests for loading microgrid configs from the Assets API."""
 
+from pathlib import Path
 from unittest.mock import AsyncMock, MagicMock
 
 import pytest
@@ -107,6 +108,32 @@ async def test_load_configs_forwards_the_component_graph_config() -> None:
     }
 
 
+async def test_load_configs_accepts_directories_for_file_layers(
+    tmp_path: Path,
+) -> None:
+    """`load_configs` can derive API IDs from config files found in a directory."""
+    config_dir = tmp_path / "configs"
+    config_dir.mkdir()
+    (config_dir / "mg-10.toml").write_text(
+        """
+        10.meta.microgrid_id = 10
+        10.meta.name = "Directory Grid"
+        10.meta.gid = 10
+        """,
+        encoding="utf-8",
+    )
+
+    configs = await load_configs(
+        default_files=config_dir,
+        assets_client=_mock_client(),
+    )
+
+    assert "10" in configs
+    assert configs["10"].ctype["pv"].formula == {
+        "AC_POWER_ACTIVE": "COALESCE(#4, #2, 0.0)"
+    }
+
+
 async def test_load_configs_rejects_a_component_graph_config_without_a_client() -> None:
     """A component graph config is only meaningful with an Assets API client."""
     with pytest.raises(ValueError, match="requires an assets_client"):