create-arktos/src/config/logger.ts

🚀 A modern Node.js backend boilerplate with TypeScript, Express, JWT authentication, Prisma ORM, PostgreSQL, and Resend email service. Includes complete authentication flow, security middleware, and database management.

import winston from 'winston';
import path from 'path';

const logLevel = process.env.LOG_LEVEL || 'info';
const logFile = process.env.LOG_FILE || 'logs/app.log';

// Ensure logs directory exists
import fs from 'fs';
const logDir = path.dirname(logFile);
if (!fs.existsSync(logDir)) {
  fs.mkdirSync(logDir, { recursive: true });
}

const logFormat = winston.format.combine(
  winston.format.timestamp({
    format: 'YYYY-MM-DD HH:mm:ss',
  }),
  winston.format.errors({ stack: true }),
  winston.format.json(),
  winston.format.prettyPrint()
);

const consoleFormat = winston.format.combine(
  winston.format.colorize(),
  winston.format.timestamp({
    format: 'HH:mm:ss',
  }),
  winston.format.printf(({ timestamp, level, message, ...meta }) => {
    return `${timestamp} [${level}]: ${message} ${Object.keys(meta).length ? JSON.stringify(meta, null, 2) : ''}`;
  })
);

const logger = winston.createLogger({
  level: logLevel,
  format: logFormat,
  defaultMeta: { service: 'arktos-backend' },
  transports: [
    // File transport
    new winston.transports.File({
      filename: logFile,
      handleExceptions: true,
      maxsize: 5242880, // 5MB
      maxFiles: 5,
    }),
    // Error file transport
    new winston.transports.File({
      filename: path.join(logDir, 'error.log'),
      level: 'error',
      handleExceptions: true,
      maxsize: 5242880, // 5MB
      maxFiles: 5,
    }),
  ],
});

// Console transport for non-production environments
if (process.env.NODE_ENV !== 'production') {
  logger.add(
    new winston.transports.Console({
      format: consoleFormat,
      handleExceptions: true,
    })
  );
}

// Handle uncaught exceptions and unhandled rejections
process.on('uncaughtException', (error) => {
  logger.error('Uncaught Exception:', error);
  process.exit(1);
});

process.on('unhandledRejection', (reason, promise) => {
  logger.error('Unhandled Rejection at:', promise, 'reason:', reason);
});

export default logger;