Uncaught exception when logging object with circular structure

If the option “json” is set to “true” given arguments are converted to JSON. If the argument has circular structures (as it can happen easily in express environments) the formatting command fails with an exception.

This happens for the console transport beginning with line 37

  if (this.json) {
    this.stringify = options.stringify || function (obj) {
      return JSON.stringify(obj, null, 2);
    };
  }

This also happens for the winston-daily-rotate-file transport

IMHO a logger should never fail while formatting the given object. Instead I would prefer if the argument in question would be omitted from logging.

What do you think?

I can provide patches if you agree.

[brrian]

I was able to get around this by specifying a “stringify” param in the options and using a library like circular-json:

const logger = new winston.Logger({
  transports: [
    new (winston.transports.File)({
      filename: 'errors.log',
      level: 'warn',
      handleExceptions: true,
      stringify(obj) {
        return CircularJSON.stringify(obj);
      }
    })
  ],
  exitOnError: false
});

[StrongBearCeo]

Any update on this issue?