Here is my logger.js with winston": "^3.1.0

logger.js

const { createLogger, format, transports } = require('winston');
const { combine, timestamp, printf, colorize, splat } = format;

const myFormat = printf((info) => {
  if (info.meta && info.meta instanceof Error) {
    return `${info.timestamp} ${info.level} ${info.message} : ${info.meta.stack}`;
  }else if(info.stack){
    return `${info.timestamp} ${info.level} ${info.message} : ${info.stack}`;
  }
  return `${info.timestamp} ${info.level}: ${info.message}`;
});

const LOG_LEVEL = process.env.LOG_LEVEL || 'debug';
const logger = createLogger({
  transports: [
    new (transports.Console)(
      {
        level: LOG_LEVEL,
        format: combine(
          colorize(),
          timestamp(),
          splat(),
          myFormat
        )
      }
    )
  ]
});
module.exports = logger;