​

const myObj = { 

    a: 1,

  b:'foo',

  c: '',

  d: null,

  e: undefined,

  f: {v: 1, w:'foo', x: '', y: null, z: undefined, m: {a:'asd'}}

  };

​

const removeEmpty = (obj) => 

  Object.keys(obj)

    .filter(f => obj[f] != null)

    .reduce((r, i) => 

      typeof obj[i] === 'object' ? 

        {...r, [i]: removeEmpty(obj[i])} :  // recurse.

        {...r, [i]: obj[i]},

      {});

​

console.log(removeEmpty(myObj));