Message not encoded on 'info' object using triple-beam

Please tell us about your environment:

• winston version?
  • winston@2
  • winston@3
• node -v outputs:
• Operating System? (Windows, macOS, or Linux)
• Language? (all | TypeScript X.X | ES6/7 | ES5 | Dart)

What is the problem?

In the Console transport, the message is read from the info object with the following logic:

const { LEVEL, MESSAGE } = require('triple-beam');
...
  log() {
    ....
    console._stderr.write(`${info[MESSAGE]}${this.eol}`);

The problem is that the message is placed on the info object using a standard 'message' string key:

      this.write({ [LEVEL]: level, level, message: msg });

What do you expect to happen instead?

Shouldn’t the message be placed on the info object using the triple-beam MESSAGE symbol?

      this.write({ [LEVEL]: level, level, [MESSAGE]: msg, message: msg });

[GeeWee]

This is crazy confusing behaviour - I just spent a few hours debugging this. Let me provide an example:

const customFormat = winston.format((info, opts) => {
  info.message = 'my less cool message';
  return info;
});

// Example of using a custom format taken from 
// https://github.com/winstonjs/winston#formats
const requestLogger = winston.createLogger({
  level: 'debug',
  // format: winston.format.simple(),
  format: winston.format.combine(
    winston.format.label({ label: 'right meow!' }),
    winston.format.timestamp(),
    customFormat(),
    // note no finalizing format, but there isn't in the docs either!
  ),
  transports: [
    new winston.transports.Console()
  ]
});

This simply logs undefined, when according to the docs it should work. I spent a few hours before finding out you have to set info[MESSAGE] with the symbol from triple-beam. I think we should log an error if there’s no info[MESSAGE] and document that you have to finish with a “finalizing logger” - there’s no real mention of them in the docs.

Edit: Looking at it, I see that instead of using winston.format to create the custom format, it’s using printf. Perhaps all you need is some documentation in the implementing custom format docs then.

[indexzero]

This is something we should consider, but it is currently by design. This is a corner case where someone has opted to not include a “finalizing formats”:

• json
• logstash
• printf
• prettyPrint
• simple

All of these would set the MESSAGE symbol for you. Does that make sense @jd-carroll?