Lodash remove duplicates from nested array

Question

Just getting started looking over lodash and stuck trying to figure out how to remove duplicates from arrays within nested objects.

Working with loop:

const _ = require('lodash');

let data = {
    "deviceA": {
        "serviceA": [
            "Foo",
            "Bar",
            "Foo Bar A",
            "Foo Bar A",
            "Foo Bar A"
        ],
        "serviceB": [
            "Foo",
            "Bar",
            "Foo Bar B",
            "Foo Bar B",
            "Foo Bar B"
        ]
    }
}


for (const key in data) {
    for (const key2 in data[key]) {
        data[key][key2] = _.uniqWith(data[key][key2], _.isEqual)
    }
}

console.log(data)

Is it possible using purely lodash to parse a nested object and update an array to remove duplicates without using a for loop?

Answer 1

I think you can consider a solution without lodash, below is an example of how this can be implemented natively using pure js.

 let data = { "deviceA": { "serviceA": [ "Foo", "Bar", "Foo Bar A", "Foo Bar A", "Foo Bar A" ], "serviceB": [ "Foo", "Bar", "Foo Bar B", "Foo Bar B", "Foo Bar B" ] } } const noDup = Object.entries(data).reduce((p, n) => { const a = Object.entries(n[1]).reduce((p1, n1) => ({...p1, [n1[0]]: [...new Set(n1[1])]}), {}) return {...p, [n[0]]: a} }, {}) console.log(noDup)

Answer 2

You can combine uniq and mapValues to achieve it.

 let data = { "deviceA": { "serviceA": [ "Foo", "Bar", "Foo Bar A", "Foo Bar A", "Foo Bar A" ], "serviceB": [ "Foo", "Bar", "Foo Bar B", "Foo Bar B", "Foo Bar B" ] }, "deviceB": { "serviceA": [ "A", "A", "Foo Bar A", ], "serviceB": [ "B", "B", "Foo Bar B", ] } } const items = _.mapValues(data, (device) => _.mapValues(device, (service) =>_.uniq(service))) console.log(items)

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