从数组中删除空对象，然后如果结果数组为空，则从父对象中删除

Question

As the title states, I'm attempting to essentially clean an object to prepare it for POSTing to an API.

The API endpoint does not allow for the empty arrays.

So let's say I have a POST object that looks like this -

{
  "Addresses": [
    {}
  ],
  "Phones": [
    {}
  ],
  "FirstName": "Foo",
  "LastName": "Bar",
  "EmailAddress": "foobar@internet.com",
  "Name": "FooBar"
}

I believe I clean empty objects from the arrays using something like this -

  var addrArr = input.Addresses;
  var phoneArr = input.Phones;
  
    var newAddrArray = addrArr.filter(value => Object.keys(value).length !== 0);
    var newPhoneArray = phoneArr.filter(value => Object.keys(value).length !== 0);

  
  return {
Addresses : newAddrArray,
Phones: newPhoneArray
}

This removes the empty objects from the array. However, this leaves two empty arrays. My thoughts are it would be best to clean the empty objects out, then determine if these arrays are empty, and if they are, (where I need help) remove them from the parent object.

Any help on how to handle this, or, how to do this more efficiently is much appreciated.

Answer 1

To make it generic (for arbitrary nested data structures), you could use a recursive solution so that there is some cascading effect after you clean out an empty object, making the wrapping object empty, ...etc.

Assuming you also want to remove undefined as values, then return undefined for anything that is not primitive and has no keys, and let the caller remove keys that so receive undefined values.

Code:

 function clean(obj) { if (Object(obj) !== obj) return obj; // primitives are kept obj = Array.isArray(obj) ? obj.map(clean).filter(v => v !== undefined) : Object.fromEntries( Object.entries(obj).map(([k, v]) => [k, clean(v)]) .filter(([_, v]) => v !== undefined) ); return Object.keys(obj).length ? obj : undefined; } // Demo let input = { "Addresses": [{}], "Phones": [{}], "FirstName": "Foo", "LastName": "Bar", "EmailAddress": "foobar@internet.com", "Name": "FooBar" }; console.log(clean(input));

Answer 2

Is the following what you are asking for?

const addrArr = input.addrArr;
const phoneArr = input.phoneArr;
  
const newAddrArray = addrArr.filter(value => Object.keys(value).length !== 0);
const newPhoneArray = phoneArr.filter(value => Object.keys(value).length !== 0);

const r = {};
if (newAddrArray.length > 0) r.Addresses = newAddrArray;
if (newPhoneArray.length > 0) r.Phones = newPhoneArray;

return r;

Answer 3

Seems strange that the API wouldn't support empty arrays. Regardless, this is definitely possible to work around.

const payload = {
  "Addresses": [
    {}
  ],
  "Phones": [
    {}
  ],
  "FirstName": "Foo",
  "LastName": "Bar",
  "EmailAddress": "foobar@internet.com",
  "Name": "FooBar"
};

let cleanedPayload = {
  "FirstName": payload.FirstName,
  "LastName": payload.LastName,
  "EmailAddress": "foobar@internet.com",
  "Name": "FooBar"
};

const isNotEmpty = obj => Object.keys(obj).length !== 0;

const hasPhoneNumbers = payload.Phones.filter(isNotEmpty).length > 0;
const hasAddresses = payload.Addresses.filter(isNotEmpty).length > 0;

if(hasPhoneNumbers) {
  cleanedPayload.Phones = payload.Phones;
}
if(hasAddresses) {
  cleanedPayload.Addresses = payload.Addresses;
}

// pseduo-code
api.post('/my/url', cleanedPayload);

To help clean up this code a bit you can use a library like https://ramdajs.com/ or https://lodash.com/ , but definitely not necessary.