How to merge common properties in array of Objects using Javascript?

Question

This is my data.

[
 {
  "author":
   {
     "id":"101",
     "label:"abc"
   },
   "books":
   {
      "id":"1"
   }
 },
  {
   "author":
   {
     "id":"101",
     "label:"abc"
   },
   "books":
   {
      "id":"2"
   }
  }
]

In the above array contains list of objects, first object first property and second object first property values are same any time, but remaining properties values are different from every time. so different properties values are push into one array like , i want to get output like this

Output:-

[
{
   "author":
   {
     "id":"101",
     "label:"abc",
     "books":[
      {"id":"1"},
      {"id":"2"}
      ]
   }
}
]

use snippets to show running code. You did not include efforts so the snippets do not run — mplungjan, Jul 06 '18 at 11:11
Possible duplicate of [How can I merge properties of two JavaScript objects dynamically?](https://stackoverflow.com/questions/171251/how-can-i-merge-properties-of-two-javascript-objects-dynamically) — Nikola Lukic, Jul 06 '18 at 11:18
Hi Nikola, how to remove first property from every object in array — durga siva kishore mopuru, Jul 06 '18 at 12:14

score 0 · Answer 1 · answered Jul 06 '18 at 12:29

I can help you out ;) You can use Array.prototype.reduce and ES6 deep object destructuring assignment for aggregation of data, and Array.prototype.map - for generating the desired output:

const data = [{author:{id:"101",label:"abc"},books:{id:"1"}},{author:{id:"101",label:"abc"},books:{id:"2"}}];

const dataObj = data.reduce((all, { author: { id: author_id, label }, books: { id: book_id } }) => {

    if (!all.hasOwnProperty(author_id)) {
        all[author_id] = { id: author_id, label, books: [] };
    }

    all[author_id].books.push({ id: book_id });

    return all;

}, {});

const result = Object.keys(dataObj).map(k => ( { author: dataObj[k] } ) );

console.log(result);

How to merge common properties in array of Objects using Javascript?

1 Answers1