feat: refactor config file arguments of mg data and mg config classes

The `load_configs` static method has been refactored to offer a more
flexible and explicit way of providing configuration files.

Previously, the method accepted a *paths argument. The signature has
been changed to now accept two distinct optional parameters:

* The first argument accepts a single configuration file or a list of
  files.
* The second argument accepts a directory.

For both parameters, inputs can be provided as either String or Path
objects. It is mandatory to provide at least one of these arguments. The
`MicrogridConfig` class will attempt to load all specified configuration
files although the content of the loaded configuration files is not yet
validated.

The `MicrogridData` class now accepts a dict of `MicrogridConfigs` as
returned by `MicrogridData.load_configs` instead of a path.

Signed-off-by: Matthias Wende <[email protected]>

Author: matthias-wende-frequenz

src/frequenz/data/microgrid/component_data.py

@@ -24,30 +24,20 @@ def __init__(
         server_url: str,
         auth_key: str,
         sign_secret: str,
-        microgrid_config_path: str | list[str],
+        microgrid_configs: dict[str, MicrogridConfig] | None = None,
     ) -> None:
         """Initialize microgrid data.
 
         Args:
             server_url: URL of the reporting service.
             auth_key: Authentication key to the service.
             sign_secret: Secret for signing requests.
-            microgrid_config_path: Path(s) to the config file with microgrid components.
-
-        Raises:
-            ValueError: If no microgrid config path is provided.
+            microgrid_configs: MicrogridConfig dict mapping microgrid IDs to MicrogridConfigs.
         """
+        self._microgrid_configs = microgrid_configs
         self._client = ReportingApiClient(
             server_url=server_url, auth_key=auth_key, sign_secret=sign_secret
         )
-        paths = (
-            [microgrid_config_path]
-            if isinstance(microgrid_config_path, str)
-            else microgrid_config_path
-        )
-        if len(paths) < 1:
-            raise ValueError("At least one microgrid config path must be provided")
-        self._microgrid_configs = MicrogridConfig.load_configs(*paths)
 
     @property
     def microgrid_ids(self) -> list[str]:
@@ -98,6 +88,8 @@ async def metric_data(  # pylint: disable=too-many-arguments
             ctype: mcfg.formula(ctype, metric.upper()) for ctype in component_types
         }
 
+        logging.debug("Formulas: %s", formulas)
+
         metric_enum = Metric[metric.upper()]
         data = [
             sample

src/frequenz/data/microgrid/config.py

@@ -3,11 +3,15 @@
 
 """Configuration for microgrids."""
 
+import logging
 import re
 import tomllib
 from dataclasses import dataclass
+from pathlib import Path
 from typing import Any, Literal, cast, get_args
 
+_logger = logging.getLogger(__name__)
+
 ComponentType = Literal["grid", "pv", "battery", "consumption", "chp", "ev"]
 """Valid component types."""
 
@@ -286,22 +290,71 @@ def formula(self, component_type: str, metric: str) -> str:
         return formula
 
     @staticmethod
-    def load_configs(*paths: str) -> dict[str, "MicrogridConfig"]:
+    def load_configs(
+        microgrid_config_files: str | Path | list[str | Path] | None = None,
+        microgrid_config_dir: str | Path | None = None,
+    ) -> dict[str, "MicrogridConfig"]:
         """Load multiple microgrid configurations from a file.
 
         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.
 
         Args:
-            *paths: Path(es) to the config file(s).
+            microgrid_config_files: Path to a single microgrid config file or list of paths.
+            microgrid_config_dir: Directory containing multiple microgrid config files.
 
         Returns:
             Dictionary of single microgrid formula configs with microgrid IDs as keys.
+
+        Raises:
+            ValueError: If no config files or dir is provided, or if no config files are found.
         """
-        microgrid_configs = {}
-        for config_path in paths:
-            with open(config_path, "rb") as f:
+        if microgrid_config_files is None and microgrid_config_dir is None:
+            raise ValueError(
+                "No microgrid config path or directory provided. "
+                "Please provide at least one."
+            )
+
+        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]
+
+        if microgrid_config_dir:
+            if Path(microgrid_config_dir).is_dir():
+                config_files += list(Path(microgrid_config_dir).glob("*.toml"))
+            else:
+                raise ValueError(
+                    f"Microgrid config directory {microgrid_config_dir} "
+                    "is not a directory"
+                )
+
+        if len(config_files) == 0:
+            raise ValueError(
+                "No microgrid config files found. "
+                "Please provide at least one valid config file."
+            )
+
+        microgrid_configs: dict[str, "MicrogridConfig"] = {}
+
+        for config_path in config_files:
+            if not config_path.is_file():
+                _logger.warning("Config path %s is not a file, skipping.", config_path)
+                continue
+
+            with config_path.open("rb") as f:
                 cfg_dict = tomllib.load(f)
                 for microgrid_id, mcfg in cfg_dict.items():
+                    _logger.debug(
+                        "Loading microgrid config for ID %s from %s",
+                        microgrid_id,
+                        config_path,
+                    )
                     microgrid_configs[microgrid_id] = MicrogridConfig(mcfg)
+
         return microgrid_configs