Javascript – convert array multi level to single level

I am trying to map a complex object array document to a single level array. For example

const data = [
    {
        "id": 1,
        "name": "Beauty",
        "children": {
            "0": {
                "id": 5,
                "parent_id": 1,
                "name": "Dermatology",
                "code": "dermatology",
                "status": 1,
                "updated_at": 1678262275,
                "created_at": 1678262275
            },
            "1": {
                "id": 7,
                "parent_id": 1,
                "name": "Plastic surgery",
                "code": "plastic_surgery",
                "status": 1,
                "updated_at": 1678262275,
                "created_at": 1678262275
            }
        }
    },
    {
        "id": 2,
        "name": "Healthiness",
        "children": {
            "0": {
                "id": 11,
                "parent_id": 2,
                "name": "Ophthalmology",
                "code": "ophthalmology",
                "status": 1,
                "updated_at": 1678262275,
                "created_at": 1678262275
            },
            "1": {
                "id": 13,
                "parent_id": 2,
                "name": "Pediatrics",
                "code": "pediatrics",
                "status": 1,
                "updated_at": 1678262275,
                "created_at": 1678262275
            },
        }
    }
]

The objective is to turn the array into something like this regardless of the complexity.
Basically, if loop through each item in the array and get children item and add parent_name for them

[
    {
        "id": 5,
        "name": "Dermatology",
        "parent_id": 1,
        "parent_name": "Beauty"
    },
    {
        "id": 7,
        "name": "Plastic surgery",
        "parent_id": 1,
        "parent_name": "Beauty"
    },
    {
        "id": 11,
        "name": "Ophthalmology",
        "parent_id": 2,
        "parent_name": "Healthiness"
    },
    {
        "id": 13,
        "name": "Pediatrics",
        "parent_id": 2,
        "parent_name": "Healthiness"
    },
]

My code here, but result not I expect.

let cusData = data
          .map((item) => item.children)
          .flat()
          .map((child) => {
            return {id: child.id, name: child.name, parent_id: child.parent_id}
          });

Thank you a lots

>Solution :

Try like below:

const data = [ { id: 1, name: "Beauty", children: { 0: { id: 5, parent_id: 1, name: "Dermatology", code: "dermatology", status: 1, updated_at: 1678262275, created_at: 1678262275, }, 1: { id: 7, parent_id: 1, name: "Plastic surgery", code: "plastic_surgery", status: 1, updated_at: 1678262275, created_at: 1678262275, }, }, }, { id: 2, name: "Healthiness", children: { 0: { id: 11, parent_id: 2, name: "Ophthalmology", code: "ophthalmology", status: 1, updated_at: 1678262275, created_at: 1678262275, }, 1: { id: 13, parent_id: 2, name: "Pediatrics", code: "pediatrics", status: 1, updated_at: 1678262275, created_at: 1678262275, }, }, }, ];

let cusData = data.flatMap(({ name: parent_name, children }) =>
  Object.values(children).map(({ id, name, parent_id }) => ({
    id,
    name,
    parent_id,
    parent_name,
  }))
);

console.log(cusData);

I have renamed the name in parent level as parent_name after destructuring

Using Array.prototype.flatMap() and Object.values()