How to extract values from JSON using JSONPath expression

Question

I have data in JSON format and it looks like this:

{
    "book": [{
        "category": "reference",
        "author": "Nigel Rees",
        "title": "Sayings of the Century",
        "price": 8.95
    }, {
        "category": "fiction",
        "author": "Evelyn Waugh",
        "title": "Sword of Honour",
        "price": 12.99
    }]
}

I want to extract only values corresponding to each object inside 'book' in form of array.

My output should look something like this:

[
    "reference",
    "Nigel Rees",
    "Sayings of the Century",
    8.95
],
[
    "fiction",
    "Evelyn Waugh",
    "Sword of Honour",
    12.99
]

Is there any way to do something like this using JSONPath Expression.

Answer 1

Just map the values of each object?

const data = {
  "book": [{
    "category": "reference",
    "author": "Nigel Rees",
    "title": "Sayings of the Century",
    "price": 8.95
  }, {
    "category": "fiction",
    "author": "Evelyn Waugh",
    "title": "Sword of Honour",
    "price": 12.99
  }]
};

const extractedValues = data.book.map(Object.values);

console.log(extractedValues);

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If you want to guarantee order, you could supply a key array:

const data = {
  "book": [{
    "category": "reference",
    "author": "Nigel Rees",
    "title": "Sayings of the Century",
    "price": 8.95
  }, {
    "category": "fiction",
    "author": "Evelyn Waugh",
    "title": "Sword of Honour",
    "price": 12.99
  }]
};

const extractValues = (arr, ...keys) => arr.map(obj => keys.map(key => obj[key]));

const extractedValues = extractValues(data.book, 'category', 'author', 'title', 'price');

console.log(extractedValues);

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