Parsing URL params

Lets say we want to parse the GET params of an URL with a long list of params into an object for easy consumption. The built-in URLSearchParams() function gives us an iterator of all params in [key, value] arrays, which is efficient, but for legibility it is probably a better idea to convert them into a simple lookup object.

Example URL

https://foo.bar/data?limit=35&offset=0&sort=-updated_at&fields=id,version

To get structured params we can use URL() and URLSearchParams()

const url = new URL(s)
const urlParams = new URLSearchParams(url.search)

This gives us an iterator at params.entries(), with [key, value] arrays as entries.

const paramArray = Array.from(urlParams.entries())

[
    [
        "limit",
        "35"
    ],
    [
        "offset",
        "0"
    ],
    [
        "sort",
        "-updated_at"
    ],
    [
        "fields",
        "id,version"
    ]
]

Lets assume the params have no duplicate keys. We can parse these arrays into a more accessible object:

const arrayObjects = paramArray.map(([key, value]) => ({[key]: value}))
const params = Object.assign({}, ...arrayObjects)

{
    "limit": "35",
    "offset": "0",
    "sort": "-updated_at",
    "fields": "id,version"
}