Isolate configuration concerns

Keep configuration settings separate from application code by using environment variables or dedicated configuration files. This promotes better maintainability, security, and flexibility across different deployment environments.

Key practices:

1. Use environment variables for sensitive or environment-specific configuration

   import os
      
   # Read configuration from environment variables with defaults
   database_url = os.getenv("DATABASE_URL", "sqlite:///default.db")
   debug_mode = os.getenv("DEBUG_MODE", "False") == "True"
   

2. Isolate project dependencies with virtual environments Create virtual environments for each project to manage dependencies independently and avoid conflicts:

   $ python -m venv .venv
   $ source .venv/bin/activate  # Linux/macOS
   $ .venv\Scripts\Activate.ps1  # Windows PowerShell
   

3. Document configuration options clearly Provide comprehensive documentation of all configuration options, including:
   • Expected variable types
   • Default values
   • Example usage
   • Possible values and their impact
4. Consider using a centralized configuration manager For more complex applications, implement a dedicated configuration class:

   from pydantic_settings import BaseSettings
      
   class Settings(BaseSettings):
       database_url: str = "sqlite:///default.db"
       api_key: str
       debug_mode: bool = False
          
       class Config:
           env_file = ".env"
      
   settings = Settings()
   

By separating configuration from code, you can adapt your application to different environments without changing the codebase, simplify testing, and enhance security by keeping sensitive information out of your repository.