MCP Server Template

""" Centralized Configuration Management Provides environment-aware configuration using Pydantic for validation and type safety. Supports both environment variables and default values. """ import os from typing import Literal, Optional from pydantic import BaseModel, Field class Settings(BaseModel): """Main configuration class with environment variable support""" # Server Configuration server_name: str = Field( default="MCP Server Template", description="Name of the MCP server" ) host: str = Field( default="0.0.0.0", description="Host to bind the server to" ) port: int = Field( default=8080, description="Port to bind the server to" ) transport: Literal["streamable-http", "sse"] = Field( default="streamable-http", description="Transport protocol to use" ) # Logging Configuration log_level: str = Field( default="INFO", description="Logging level" ) log_format: str = Field( default="[%(levelname)s]: %(message)s", description="Logging format string" ) # Environment Configuration environment: Literal["development", "production", "testing"] = Field( default="development", description="Runtime environment" ) # Version Information version: str = Field( default="2.0.1", description="Server version" ) # Weather Service Configuration weather_api_key: Optional[str] = Field( default=None, description="OpenWeatherMap API key" ) use_mock_weather_data: bool = Field( default=True, description="Use mock weather data instead of real API calls" ) model_config = { # Enable environment variable loading with MCP_ prefix "env_prefix": "MCP_", "case_sensitive": False, "env_file": ".env", "env_file_encoding": "utf-8" } @classmethod def from_env(cls) -> "Settings": """Create settings instance from environment variables""" # Manual environment variable handling for compatibility env_vars = {} # Map environment variables to settings env_mappings = { "MCP_SERVER_NAME": "server_name", "MCP_HOST": "host", "MCP_PORT": "port", "MCP_TRANSPORT": "transport", "MCP_LOG_LEVEL": "log_level", "MCP_LOG_FORMAT": "log_format", "MCP_ENVIRONMENT": "environment", "MCP_VERSION": "version", "MCP_WEATHER_API_KEY": "weather_api_key", "MCP_USE_MOCK_WEATHER_DATA": "use_mock_weather_data", "WEATHER_API_KEY": "weather_api_key", # Alternative naming "USE_MOCK_WEATHER_DATA": "use_mock_weather_data", # Alternative naming "PORT": "port" # Cloud Run compatibility } for env_key, setting_key in env_mappings.items(): if env_key in os.environ: value = os.environ[env_key] # Convert port to int if setting_key == "port": try: value = int(value) except ValueError: continue # Convert boolean values elif setting_key == "use_mock_weather_data": value = value.lower() in ("true", "1", "yes", "on") env_vars[setting_key] = value return cls(**env_vars) # Singleton pattern for settings _settings: Settings | None = None def get_settings() -> Settings: """Get singleton settings instance""" global _settings if _settings is None: _settings = Settings.from_env() return _settings def reset_settings(): """Reset settings singleton (useful for testing)""" global _settings _settings = None