V3: New formatters are not equivalent to old formatters, broken logs after migration

[alexilyaev]

Please tell us about your environment:

• winston version?
  • [ ] winston@2
  • [x] winston@3
• node -v outputs: v10.4.1
• Operating System? macOS High Sierra v10.13.5
• Language? ES6

What is the problem?

I've followed the upgrade to 3.0 doc, and when I was done, my logs were broken.

V2 supported multiple arguments to log functions, and using common format options, pretty printed Objects/Arrays/Errors nicely.

So these logs worked in V2:

const consoleLogger = new winston.Logger({
    transports: [
      new winston.transports.Console({
        level: 'info',
        colorize: true,
        prettyPrint: true,
        timestamp: true
      })
    ]
}),

consoleLogger.info({ one: 1, two: 2, three: 3 });
consoleLogger.info(chalk.blue('[TEST]:'), { one: 1, two: 2, three: 3 });
consoleLogger.info(chalk.blue('[TEST]:'), ...['one', 2, { 3: 3 }]);
consoleLogger.error(chalk.blue('[ERR]:'), new Error('Boo face'));

But in V3, multiple arguments are no longer supported, only meta is supported and only as an Object. Plus the equivalent formatters do not yield the same result.

const consoleLogger = winston.createLogger({
  level: 'info',
  format: winston.format.combine(
    winston.format.timestamp(),
    winston.format.colorize(),
    winston.format.prettyPrint(),
    // winston.format.simple()
  ),
  transports: [new winston.transports.Console()]
}),

consoleLogger.info({ one: 1, two: 2, three: 3 });
consoleLogger.info(chalk.blue('[TEST]:'), { one: 1, two: 2, three: 3 });
consoleLogger.info(chalk.blue('[TEST]:'), 'string here is ignored');
consoleLogger.info(chalk.blue('[TEST]:'), ...['one', 2, { 3: 3 }]);
consoleLogger.error(chalk.blue('[ERR]:'), new Error('Boo face'));

Even if I add the simple formatter, it's still not the same:

What do you expect to happen instead?

• The migration doc should mention this fundamental change in behavior and how to resolve it:
  • Multiple arguments are treated differently
  • Objects as message are not pretty printed
  • Error Object is ignored (I saw there's an open issue for that)
  • Formatters order matters
• I think Winston should support the multiple arguments notation, as it is a very common usage of console.log and really is much easier to use when you need to log a string and then an Object, etc. (specifically when using the Console transport).
• The new formatters should yield the previous behavior when using the same setup

[respinha]

+1

The documentation is a bit superficial regarding winston.Format and the provided examples such as this one do not result in the expected output.

[indexzero]

PR would be welcome to update that example @respinha-ribeiro. Will take a look at this in depth and see what we can do to make the transition easier.

[indexzero]

Also @alexilyaev – winston does support the multiple argument notation, it's simply not enabled by default because it is a performance hit and as such opt-in.

Use winston.format.splat().

[respinha]

@indexzero I can gladly post a PR but currently I'm unable to understand how to obtain the standard notation. I tried adding winston.format.splat I just get a weird message like the ones shown by @alexilyaev.

[tagyoureit]

I was making the same comments (objects/arrays) aren't formatting the same in the Gitter chatroom. Seems that the previous options.meta isn't treated the same way. Would be great to understand the differences and how to fix moving forward.

[nemozny]

+1

After maybe 2 hours of trying to obtain the same logging format in V3 as in the previous version, I have to say I have to downgrade. I like the custom formatter and format.combine and everything, but either

• coloring doesn't work
• simple format output doesn't work (no JSON)
• printing out objects (JSON) doesn't work - I don't see any reason why use custom formater with JSON.stringify
• or combination of the above

I just want logger.error("error"), logger.info(object), logger.info(array) and no hustle.

[indexzero]

All of those features work. If you'd like to share a code sample along with your shade that would be much more constructive.

Edit: @nemozny literally every feature you could not get working has an example in the examples/ directory. Please read those and feel free to add any you feel should be there.