Displaying objects in logs

Question

I am trying to log objects in my logs, in somewhat readable format.

This is currently what I am working with:

const { format, createLogger, transports } = require("winston");

const { combine, timestamp, printf, errors, splat, simple } = format;

const LEVEL = Symbol.for("level");

const customLevels = {
  levels: {
    trade: 0,
    purchase: 1,
    selling: 2,
    withdraw: 3,
    priceAdjust: 4,
  },
};

const logFormat = printf(({ message, timestamp }) => {
  return `${timestamp} ${message}`;
});

function filterOnly(level) {
  return format(function (info) {
    if (info[LEVEL] === level) {
      return info;
    }
  })();
}

const logger = createLogger({
  format: combine(errors({ stack: true }), timestamp({ format: "YYYY-MM-DD HH:mm:ss" }), logFormat, splat(),),
  levels: customLevels.levels,
  transports: [
    new transports.File({ level: "trade", format: filterOnly("trade"), filename: "logs/trade.log" }),
    new transports.File({ level: "withdraw", format: filterOnly("withdraw"), filename: "logs/withdraw.log" }),
  ],
});

if (process.env.NODE_ENV !== "production") {
  logger.add(
    new winston.transports.Console({
      format: winston.format.simple(),
    })
  );
}

if I pass something as:

logger.trade("Doing trade:", {some object});

I get output in the logs only as:

2022-05-15 11:49:44 Doing trade:

What I am missing to see the object as well?

I have tried, using %O, %j utils, before object, but then getting only

2022-05-15 11:49:44 Doing trade %O:

I was able to display objects by using format.simple(), but then it becomes not really nice readable format.