@evolution-gym/logger

Shared logging utilities for Evolution Gym microservices using Pino.

Installation

npm install @evolution-gym/logger

Usage

Basic Usage

import { logger } from '@evolution-gym/logger';

logger.info('Service started');
logger.error({ err: error }, 'Failed to process request');
logger.debug({ userId: '123' }, 'User logged in');

Create Custom Logger

import { createLogger } from '@evolution-gym/logger';

const logger = createLogger({
  serviceName: 'auth-service',
  level: 'debug',
  prettyPrint: true // For development
});

logger.info('Auth service initialized');

With Context

const childLogger = logger.child({
  requestId: '550e8400-e29b-41d4-a716-446655440000',
  tenantId: 'gym-123'
});

childLogger.info('Processing payment');
childLogger.error({ err }, 'Payment failed');

Environment Variables

• LOG_LEVEL - Set log level (trace, debug, info, warn, error, fatal)
• SERVICE_NAME - Service name for log context
• NODE_ENV - Set to 'production' to disable pretty printing

Log Levels

• trace - Very detailed logs
• debug - Debug information
• info - General information
• warn - Warning messages
• error - Error messages
• fatal - Fatal errors

Best Practices

1. Always include context: Add relevant data to log messages

logger.info({ userId, action: 'login' }, 'User authenticated');

2. Use child loggers for request tracking:

const requestLogger = logger.child({ requestId });

3. Log errors with stack traces:

logger.error({ err: error }, 'Operation failed');

4. Use structured logging:

// Good
logger.info({ userId, amount, currency }, 'Payment processed');

// Avoid
logger.info(`Payment processed for user ${userId}`);

License

MIT