Transform javascript object

Question

This simple (as before, I thought) transformation of a JavaScript object defeats me. I would like to flatten this object in the following way.

This is what I have:

{
    "1": {
        "group": "Clothes",
        "brand": {
            "0": {
                "brand_id": "12",
                "brand_name": "Adidas"
            },
            "1": {
                "brand_id": "15",
                "brand_name": "Zara"
            }
        }
    },
    "2": {
        "group": "Cars",
        "brand": {
            "0": {
                "brand_id": "43",
                "brand_name": "Ferrari"
            },
            "1": {
                "brand_id": "51",
                "brand_name": "BMW"
            }
        }
    }
}

And this is it, what I want to get

{0: {
    brand_id: "12",
    brand_name: "Adidas",
    group: "Clothes",
}
1: {
    brand_id: "15",
    brand_name: "Zara",
    group: "Clothes",
},
2: {
    brand_id: "43",
    brand_name: "Ferrari",
    group: "Cars",
}
3: {
    brand_id: "51",
    brand_name: "BMW",
    group: "Cars",
}}

I tried using .reduce() or .map() but ineffectively.

Answer 1

You can do:

const data = {1: {group: 'Clothes',brand: [{0: {brand_id: '12',brand_name: 'Adidas'}},{1: {brand_id: '15',brand_name: 'Zara'}}]},2: {group: 'Cars',brand: [{0: {brand_id: '43',brand_name: 'Ferrari'}},{1: {brand_id: '51',brand_name: 'BMW'}}]}};
const result = {};

Object.keys(data).forEach(k => {
  data[k].brand.forEach((b, i) => {
    result[Object.keys(result).length] = {
      brand_id: b[i].brand_id,
      brand_name: b[i].brand_name,
      group: data[k].group
    };
  });
});

console.log(result);

.as-console-wrapper { max-height: 100% !important; top: 0; }

Answer 2

This Object is kind of weird like array-like objects, but index start from 1 not 0, and lack of length.

Fix some typo first, brand should be object not array.

var objectOri = {
    1: {
        group: 'Clothes',
        brand: {
            0: {
                brand_id: "12",
                brand_name: "Adidas"
            },
            1: {
                brand_id: "15",
                brand_name: "Zara"
            }
        }
    },
    2: {
        group: 'Cars',
        brand: {
            0: {
                brand_id: "43",
                brand_name: "Ferrari"
            },
            1: {
                brand_id: "51",
                brand_name: "BMW"
            }
        }
    }
};

let arr = [];
Object.keys(objectOri).forEach(index => {
    let brand = objectOri[index].brand;
    Object.keys(brand).forEach(brIndex => {
        arr.push({
            ...brand[brIndex],
            group: objectOri[index].group
        });
    });
});


console.log(Object.assign({}, arr))

 

Also, if this obejct is a array-like object, the key should start from 0 not 1, and length is also necessary, like below.

var objectOri = {
    0: {
        group: 'Clothes',
        brand: {
            0: {
                brand_id: "12",
                brand_name: "Adidas"
            },
            1: {
                brand_id: "15",
                brand_name: "Zara"
            },
            length: 2
        }
    },
    1: {
        group: 'Cars',
        brand: {
            0: {
                brand_id: "43",
                brand_name: "Ferrari"
            },
            1: {
                brand_id: "51",
                brand_name: "BMW"
            },
            length: 2
        }
    },
    length: 2
};

let arr = [];
Array.from(objectOri).forEach(item => {
    Array.from(item.brand).forEach(brand => {
        arr.push({
            ...brand,
            group: item.group
        });
    });
});


console.log(Object.assign({}, arr))