Ramda remove nested null values

Question

I want to remove all null values from a object. Let's suppose:

const data = {
  key1: 'ok',
  key2: null,
  key3: '', // should be removed too
  key4: {
    inner_key1: 'aaa',
    inner_key2: null
  }
}

What I did was this

const clean = R.reject(R.either(R.isNil, R.isEmpty))

And this work:

{"key1":"ok","key4":{"inner_key1":"aaa","inner_key2":null}}

Except for nested objects, as you can see, inner_key2 is present, and should be filtered out.

Using ramda, how can I remove this nested values too?

Answer 1

Create a recursive function that iterates the properties after cleaning the object, and calls clean on each property, which is an object:

const { pipe, reject, either, isNil, isEmpty, map, when, is } = R

const clean = o => pipe(
  reject(either(isNil, isEmpty)),
  map(when(is(Object), clean))
)(o)

const data = {"key1":"ok","key2":null,"key3":"","key4":{"inner_key1":"aaa","inner_key2":null}}
const result = clean(data)

console.log(result)

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