Pass a simple object and a path, to generate a JSON file.

saveObjectToFile.js

// tradesList = [{},...]
// saveObjectToFile(tradesList, `./data/${symbol}_f${fromMS}_t${toMS}.json`)
const fs = require('fs');

module.exports = (object, filepath) => {
  return new Promise((resolve, reject) => {
    const objStr = JSON.stringify(object);
  
    fs.writeFile(filepath, objStr, function(err) {
      if (!err) return resolve();
    
      console.log(err)
      return reject(err);
    })
  })
};