​

​

myObj = {one: 1, two: 2, three: 3, four: {one: 1, two: 2, three: 3}}

​

// {one: 3, two: 6, three: 9}

​

    const mapObjRecursive = (obj) => {

      Object.keys(obj).forEach(key => {

        if (typeof obj[key] === 'object') obj[key] = mapObjRecursive(obj[key]);

        else obj[key] = obj[key] * 3;

      });

      return obj;

    };

​

console.log(mapObjRecursive(myObj));