gateway/modules/shared/configuration.py

"""
Utility module for configuration management.

This module provides a global APP_CONFIG object for accessing configuration from both 
config.ini files and environment variables stored in .env files, using a flat structure.
"""

import os
import logging
from typing import Any, Dict, Optional
from pathlib import Path

# Set up basic logging for configuration loading
logging.basicConfig(
    level=logging.WARNING,
    format='%(asctime)s - %(levelname)s - %(name)s - %(message)s',
    handlers=[logging.StreamHandler()]
)

# Configure logger
logger = logging.getLogger(__name__)

class Configuration:
    """
    Configuration class with attribute-style access to flattened configuration.
    """
    def __init__(self):
        """Initialize the configuration object"""
        self._data = {}
        self._configFilePath = None
        self._envFilePath = None
        self._configMtime = 0
        self._envMtime = 0
        self.refresh()
    
    def refresh(self):
        """Reload configuration from files"""
        self._loadConfig()
        self._loadEnv()
        logger.info("Configuration refreshed")
    
    def _loadConfig(self):
        """Load configuration from config.ini file in flattened format"""
        # Find config.ini file in the gateway directory
        configPath = Path(__file__).parent.parent.parent / 'config.ini'
        if not configPath.exists():
            logger.warning(f"Configuration file not found at {configPath.absolute()}")
            return
        
        self._configFilePath = configPath
        currentMtime = os.path.getmtime(configPath)
        
        # Skip if file hasn't changed
        if currentMtime <= self._configMtime:
            return
            
        self._configMtime = currentMtime

        try:
            with open(configPath, 'r') as f:
                for line in f:
                    line = line.strip()
                    # Skip empty lines and comments
                    if not line or line.startswith('#'):
                        continue
                        
                    # Parse key-value pairs
                    if '=' in line:
                        key, value = line.split('=', 1)
                        key = key.strip()
                        value = value.strip()
                        
                        # Add directly to data dictionary
                        self._data[key] = value
                
                    
        except Exception as e:
            logger.error(f"Error loading configuration: {e}")
    
    def _loadEnv(self):
        """Load environment variables from .env file"""
        # Find .env file in the gateway directory
        envPath = Path(__file__).parent.parent.parent / '.env'
        if not envPath.exists():
            logger.warning(f"Environment file not found at {envPath.absolute()}")
            return
        
        self._envFilePath = envPath
        currentMtime = os.path.getmtime(envPath)
        
        # Skip if file hasn't changed
        if currentMtime <= self._envMtime:
            return
            
        self._envMtime = currentMtime
        
        try:
            with open(envPath, 'r') as f:
                for line in f:
                    line = line.strip()
                    # Skip empty lines and comments
                    if not line or line.startswith('#'):
                        continue
                        
                    # Parse key-value pairs
                    if '=' in line:
                        key, value = line.split('=', 1)
                        key = key.strip()
                        value = value.strip()
                        
                        # Add directly to data dictionary
                        self._data[key] = value
            
            logger.info(f"Loaded environment variables from {envPath.absolute()}")
            
            # Also load system environment variables (don't override existing)
            for key, value in os.environ.items():
                if key not in self._data:
                    self._data[key] = value
                    
        except Exception as e:
            logger.error(f"Error loading environment variables: {e}")
    
    def checkForUpdates(self):
        """Check if configuration files have changed and reload if necessary"""
        if self._configFilePath and os.path.exists(self._configFilePath):
            currentMtime = os.path.getmtime(self._configFilePath)
            if currentMtime > self._configMtime:
                logger.info("Config file has changed, reloading...")
                self._loadConfig()
                
        if self._envFilePath and os.path.exists(self._envFilePath):
            currentMtime = os.path.getmtime(self._envFilePath)
            if currentMtime > self._envMtime:
                logger.info("Environment file has changed, reloading...")
                self._loadEnv()
    
    def get(self, key: str, default: Any = None) -> Any:
        """Get configuration value with optional default"""
        self.checkForUpdates()  # Check for file changes
        
        if key in self._data:
            value = self._data[key]
            # Handle secrets (keys ending with _SECRET)
            if key.endswith("_SECRET"):
                return handleSecret(value)
            return value
        return default
    
    def __getattr__(self, name: str) -> Any:
        """Enable attribute-style access to configuration"""
        self.checkForUpdates()  # Check for file changes
        
        value = self.get(name)
        if value is None:
            raise AttributeError(f"Configuration key '{name}' not found")
        return value
    
    def __dir__(self) -> list:
        """Support auto-completion of attributes"""
        self.checkForUpdates()  # Check for file changes
        return list(self._data.keys()) + super().__dir__()
    
    def set(self, key: str, value: Any) -> None:
        """Set a configuration value (for testing/overrides)"""
        self._data[key] = value

def handleSecret(value: str) -> str:
    """
    Handle secret values. Currently just returns the plain text value,
    but can be enhanced to provide actual decryption in the future.
    
    Args:
        value: The secret value to handle
        
    Returns:
        str: Processed secret value
    """
    # For now, just return the value as-is
    # In the future, this could be enhanced to decrypt values
    return value

# Create the global APP_CONFIG instance
APP_CONFIG = Configuration()