winston3.js

const logform = require('logform');
const tripleBeam = require('triple-beam');
const winston = require('winston');

const errorHunter = logform.format(info => {
  if (info.error) return info;

  const splat = info[tripleBeam.SPLAT] || [];
  info.error = splat.find(obj => obj instanceof Error);

  return info;
});

const errorPrinter = logform.format(info => {
  if (!info.error) return info;

  // Handle case where Error has no stack.
  const errorMsg = info.error.stack || info.error.toString();
  info.message += `\n${errorMsg}`;

  return info;
});

const winstonConsoleFormat = logform.format.combine(
  errorHunter(),
  errorPrinter(),
  logform.format.printf(info => `${info.level}: ${info.message}`)
);

// Configure Winston
const logger = winston.createLogger({
  transports: [new winston.transports.Console({
    format: winstonConsoleFormat,
  })],
});