Oracle Database MCP Server

# Logging System The MCP Oracle Database server uses a lightweight, dependency-free logging module for all logging operations. ## Features - ✅ **Zero Dependencies** - No external logging libraries required - ✅ **Console & File Logging** - Supports both console output and optional file logging - ✅ **Daily Log Rotation** - Automatically creates new log files each day - ✅ **Colorized Output** - ANSI color codes for easy console reading - ✅ **Log Levels** - Supports info, warn, error, and debug levels - ✅ **Audit Logging** - Special audit logging for compliance tracking - ✅ **Production-Safe** - Debug logs automatically disabled in production ## Configuration Configure logging behavior using environment variables: ```env # Enable/disable file logging (default: false) ENABLE_FILE_LOGGING=true # Directory for log files (default: ./logs) LOG_DIR=./logs # Log level (default: info) LOG_LEVEL=info # Enable audit logging (default: true) ENABLE_AUDIT_LOGGING=true # Environment mode (affects debug logging) NODE_ENV=development ``` ## Log Levels ### `info` General informational messages about application operation. ```typescript logger.info('Server started', { port: 3000 }); ``` ### `warn` Warning messages for potentially problematic situations. ```typescript logger.warn('Connection pool nearly full', { current: 9, max: 10 }); ``` ### `error` Error messages for failure conditions. ```typescript logger.error('Query failed', { error: err.message }); ``` ### `debug` Detailed debugging information (only shown in development mode). ```typescript logger.debug('Query executed', { rowCount: 100, time: 45 }); ``` ## File Logging When `ENABLE_FILE_LOGGING=true`, the logger creates daily log files in the format: ``` logs/ app-2025-10-26.log app-2025-10-27.log app-2025-10-28.log ``` Each file contains all logs for that day with timestamps and log levels: ``` 2025-10-26T10:30:00.000Z INFO: Server started {"port":3000} 2025-10-26T10:30:05.123Z INFO: Database connected {"poolSize":5} 2025-10-26T10:30:10.456Z WARN: High query load {"count":50} 2025-10-26T10:30:15.789Z ERROR: Query timeout {"query":"SELECT..."} ``` ## Audit Logging Use the `audit()` function for compliance and security logging: ```typescript import { audit } from './utils/logger.js'; audit('User query executed', { userId: 'user123', query: 'SELECT * FROM users', rowCount: 10, executionTime: 45 }); ``` Audit logs are prefixed with `[AUDIT]` and include structured metadata: ``` 2025-10-26T10:30:00.000Z INFO: [AUDIT] User query executed {"userId":"user123","query":"SELECT * FROM users","rowCount":10,"executionTime":45} ``` ## Production vs Development ### Development Mode (`NODE_ENV=development`) - All log levels appear (info, warn, error, debug) - Colorized console output - Optional file logging ### Production Mode (`NODE_ENV=production`) - Debug logs are suppressed - Only info, warn, and error appear - Colorized console output - Optional file logging ## Usage Examples ### Basic Logging ```typescript import logger from './utils/logger.js'; logger.info('Application started'); logger.warn('Cache is full'); logger.error('Connection failed'); logger.debug('Processing request', { id: 123 }); ``` ### Logging with Objects ```typescript logger.info('User logged in', { userId: 'user123', timestamp: new Date().toISOString(), ipAddress: '192.168.1.1' }); ``` Objects are automatically serialized to JSON in log files: ``` 2025-10-26T10:30:00.000Z INFO: User logged in {"userId":"user123","timestamp":"2025-10-26T10:30:00.000Z","ipAddress":"192.168.1.1"} ``` ### Audit Logging ```typescript import { audit } from './utils/logger.js'; // Log security-relevant events audit('Database query executed', { query: sql.substring(0, 500), rowCount: result.rowCount, executionTime: endTime - startTime }); ``` ## Log Rotation Log files are automatically rotated daily based on the current date: - **Automatic**: New file created each day with format `app-YYYY-MM-DD.log` - **No cleanup**: Old logs are preserved (implement external log rotation if needed) - **Single process**: Designed for single-process applications (for multi-process setups, consider a more robust solution) ### Managing Old Logs To clean up old logs, use external tools: ```bash # Keep only last 30 days of logs find ./logs -name "app-*.log" -mtime +30 -delete # Compress old logs find ./logs -name "app-*.log" -mtime +7 -exec gzip {} \; ``` ## Implementation Details The logger is implemented in `src/utils/logger.ts` using only Node.js built-in modules: - `fs` - File system operations - `path` - Path manipulation - `url` - ES module utilities No external dependencies required. ## Migration from Winston If you're upgrading from a Winston-based logger, the API is mostly compatible: ```typescript // Old (Winston) import logger from './logging/logger.js'; logger.info('message', { meta: 'data' }); // New (Lightweight logger) import logger from './utils/logger.js'; logger.info('message', { meta: 'data' }); // Same API ``` The `audit()` function is also available for backward compatibility: ```typescript import { audit } from './utils/logger.js'; audit('Event', { data: 'value' }); ```