Update config.py

settings/config.py

@@ -1,33 +1,95 @@
+#!/usr/bin/env python3
+"""
+@fileoverview Dynamic configuration loader for chain-specific settings using Pydantic V2 and yaml_config.
+This module defines a factory function to load YAML configuration files and ensures that 
+YAML settings are loaded before environment variables, allowing environment variables to override.
+"""
 from pathlib import Path
-
 from pydantic_settings import BaseSettings, PydanticBaseSettingsSource, SettingsConfigDict, YamlConfigSettingsSource
+from typing import Type, Tuple, Callable
+
+# Assuming settings/models.py exists and contains DataModels.ChainConfig
+import settings.models as DataModels 
 
-import settings.models as DataModels
+# Resolve the base directory (two levels up from this file's location)
+BASE_DIR: Path = Path(__file__).resolve().parent.parent
 
-BASE_DIR = Path(__file__).resolve().parent.parent
-settings = DataModels.Settings()
+# --- FACTORY FUNCTION ---
 
+def create_chain_config_model(config_file: Path) -> Type[DataModels.ChainConfig]:
+    """
+    Dynamically creates a Pydantic Settings class customized to load from a specific YAML file.
 
-def get_chain_settings(chain_config_file: str):
-    config_file = Path(BASE_DIR, "settings", "chains", f"{chain_config_file}")
+    This setup ensures that the YAML file is the *first* source loaded, allowing environment 
+    variables and other default sources to override the values defined in the file.
+    """
 
     class YamlChainConfig(DataModels.ChainConfig):
-        model_config = SettingsConfigDict(yaml_file=config_file)
-        file_path: str = chain_config_file
+        # 1. Pydantic Settings Configuration
+        model_config = SettingsConfigDict(
+            yaml_file=config_file,
+            extra="ignore",  # Ignore unknown fields in the YAML file for robustness
+            case_sensitive=True,
+            # Ensure proper path is handled if YAML contains relative paths
+            env_file_encoding='utf-8' 
+        )
+
+        # 2. Additional File Metadata (Non-config fields, used for reference)
+        file_path: str = config_file.as_posix()
         file_name: str = config_file.stem
 
         @classmethod
         def settings_customise_sources(
             cls,
-            settings_cls: type[BaseSettings],
+            settings_cls: Type[BaseSettings],
             init_settings: PydanticBaseSettingsSource,
             env_settings: PydanticBaseSettingsSource,
             dotenv_settings: PydanticBaseSettingsSource,
             file_secret_settings: PydanticBaseSettingsSource,
-        ) -> tuple[PydanticBaseSettingsSource, ...]:
-            sources = super().settings_customise_sources(
+        ) -> Tuple[PydanticBaseSettingsSource, ...]:
+            """
+            Customizes the order of configuration sources to load the YAML file first.
+            (YAML, then Init, Env, Dotenv, Secrets)
+            """
+            # Create the YAML source instance
+            yaml_source = YamlConfigSettingsSource(settings_cls, yaml_file=config_file)
+
+            # Retrieve default sources from the superclass
+            default_sources = super().settings_customise_sources(
                 settings_cls, init_settings, env_settings, dotenv_settings, file_secret_settings
             )
-            return YamlConfigSettingsSource(settings_cls, yaml_file=config_file), *sources
 
-    return YamlChainConfig()
+            # Return YAML source first, followed by all default sources (excluding the initial ones 
+            # returned by the super().settings_customise_sources call, as they are implicitly re-added
+            # by Python's return syntax when using the *sources spread operator in the original)
+            return (yaml_source, *default_sources)
+
+    return YamlChainConfig
+
+
+# --- PUBLIC INTERFACE ---
+
+def get_chain_settings(chain_config_file: str) -> DataModels.ChainConfig:
+    """
+    Loads and validates chain configuration from a YAML file located in the settings/chains directory.
+
+    Args:
+        chain_config_file: The filename of the YAML config (e.g., 'ethereum.yaml').
+
+    Returns:
+        An instance of the validated ChainConfig model.
+    """
+    # Use Pythonic path joining syntax
+    config_path: Path = BASE_DIR / "settings" / "chains" / chain_config_file
+
+    if not config_path.exists():
+        raise FileNotFoundError(f"Chain configuration file not found at: {config_path.as_posix()}")
+
+    # Create the dynamic class and instantiate it to load the configuration
+    YamlConfigClass = create_chain_config_model(config_path)
+
+    return YamlConfigClass()
+
+
+# --- OPTIONAL: Example of how to structure main execution (Removed the unnecessary global setting) ---
+# Example: settings = get_chain_settings("my_chain.yaml")