Object deconstruction into object declaration?

Question

I have an object which has several values I want to extract and place into another object with different keys for those values. Right now I\'m using deconstruction to extrac

Answer 1

I don't think there's anything to put them in the same statement, especially with the renaming. You could of course write your own helper function for renaming object properties.

I think it would be much cleaner though to assign the object to one variable and then repeat that multiple times, than repeating every property/variable name twice:

getProductReviewData() {
    const all = this.productReviewsStore.getAll();
    return {
        ratingDisplay: all.averageRateDisplay,
        rating:        all.rawAverageRate,
        ratingCount:   all.displayReviewCount,
        reviewIds:     all.productReviewIds,
        reviewMap:     all.productReviews
    };
}

You can also use destructuring into object properties to swap the two sides if you¹ like that better:

getProductReviewData() {
    let res = {};
    ({
        averageRateDisplay: res.ratingDisplay,
        rawAverageRate:     res.rating,
        displayReviewCount: res.ratingCount,
        productReviewIds:   res.reviewIds,
        productReviews:     res.reviewMap
    } = this.productReviewsStore.getAll());
    return res;
}

_{1: Personally I think it's just unnecessary confusing - and one line longer!}

Answer 2

You can destructure and give new key/variable values in one go. But as far as I know you can't destructure directly into a new object.

const start = {
  averageRateDisplay: 1,
  rawAverageRate: 2,
  displayReviewCount: 3,
  productReviewIds: 4,
  productReviews: 5
 };

 // destructuring with renaming of variables
 const {
   // name to match : newName
   averageRateDisplay: ratingDisplay,
   rawAverageRate: rating,
   displayReviewCount: ratingCount,
   productReviewIds: reviewIds,
   productReviews: reviewMap
} = start;

// creating new object, using property value shorthand
// https://ariya.io/2013/02/es6-and-object-literal-property-value-shorthand
const end = {
    ratingDisplay,
  rating,
  ratingCount,
  reviewIds,
  reviewMap
};

console.log(end)

Answer 3

UPD: Simple is better than complex! I like Bergi's answer =)

Probably you can declare new keys and then change them in iterations ¯_(ツ)_/¯

getProductReviewData() {
    //declare new keys
    const newKeys = {
        averageRateDisplay: "ratingDisplay",
        rawAverageRate:     "rating",
        displayReviewCount: "ratingCount",
        productReviewIds:   "reviewIds",
        productReviews:     "reviewMap"
    }
    const productReviewsStore = this.productReviewsStore.getAll();

    //return the object with replaced keys
    return Object.assign({},
      ...Object.keys(productReviewsStore)
           .filter(key => newKeys[key])
           .map(key => ({[newKeys[key]]: productReviewsStore[key]}))
    )
}