Finding Objects using Lodash with Nested Properties

Finding objects by nested properties is a common task when dealing with complex data structures like deeply nested arrays or objects. Lodash, a popular JavaScript utility library, provides methods that simplify working with deeply nested data.

Prerequisites

• Node.js
• NPM
• Lodash Library

Install Lodash:

Open your terminal and navigate to your project directory. Run the following command to install Lodash:

npm install lodash

Below are the approaches to finding objects by Nested Properties with Lodash:

Using Lodash find() method

In this approach we will use the find() method in Lodash this helps us to retrieve the first element in a collection that matches the given condition. Combining it with Lodash’s get allows us to access deeply nested properties without worrying about undefined errors.

Syntax:

_.find(collection, obj => _.get(obj, 'nested.property') === value);

Example: In below example we have nested object and we are finding the Object by Nested Properties using Lodash's find method.

const _ = require('lodash');

const users = [
    {
        id: 1, details: {
            name: 'Rohit Sharma',
            age: 28
        }
    },
    {
        id: 2, details: {
            name: 'Yuvraj Singh',
            age: 32
        }
    },
    {
        id: 3, details: {
            name: 'David Warner',
            age: 25
        }
    },
];

const result = _.find(users, user => _.get(user,
    'details.age') === 32);
console.log(result);

Output:

{ id: 2, details: { name: 'Yuvraj Singh', age: 32 } }

Using Lodash filter() method

In this approach we will use Lodash filter() method. While find returns the first matching element, filter returns all elements that match a condition. We can use Lodash’s get to access nested properties.

Syntax:

_.filter(collection, obj => _.get(obj, 'nested.property') === value);

Example: In this example we have nested objct and we will find objects which have age greater than 25 using filter method of lodash.

const _ = require('lodash');

const users = [
    {
        id: 1, details: {
            name: 'Rohit Sharma',
            age: 28
        }
    },
    {
        id: 2, details: {
            name: 'Yuvraj Singh',
            age: 32
        }
    },
    {
        id: 3, details: {
            name: 'David Warner',
            age: 25
        }
    },
    {
        id: 4, details: {
            name: 'Yashaswi Jaiswal',
            age: 20
        }
    },
];

const result = _.filter(users,
    user => _.get(user, 'details.age') > 25);
console.log(result);

Output:

[
  { id: 1, details: { name: 'Rohit Sharma', age: 28 } },
  { id: 2, details: { name: 'Yuvraj Singh', age: 32 } }
]