useQueryState hook for Next.js - Like React.useState, but stored in the URL query string

• 🧘‍♀️ Simple: the URL is the source of truth.
• 🕰 Replace history or append to use the Back button to navigate state updates
• ⚡️ Built-in converters for common object types (number, float, boolean, Date)
• ♊️ Linked querystrings with useQueryStates

$ yarn add next-usequerystate
or
$ npm install next-usequerystate

import { useQueryState } from 'next-usequerystate'

export default () => {
  const [name, setName] = useQueryState('name')
  return (
    <>
      <h1>Hello, {name || 'anonymous visitor'}!</h1>
      <input value={name || ''} onChange={e => setName(e.target.value)} />
      <button onClick={() => setName(null)}>Clear</button>
    </>
  )
}

useQueryState takes one required argument: the key to use in the query string.

Like React.useState, it returns an array with the value present in the query string as a string (or null if none was found), and a state updater function.

Example outputs for our hello world example:

If your state type is not a string, you must pass a parsing function in the second argument object.

We provide helpers for common and more advanced object types:

import { queryTypes } from 'next-usequerystate'

useQueryState('tag') // defaults to string
useQueryState('count', queryTypes.integer)
useQueryState('brightness', queryTypes.float)
useQueryState('darkMode', queryTypes.boolean)
useQueryState('after', queryTypes.timestamp) // state is a Date
useQueryState('date', queryTypes.isoDateTime) // state is a Date
useQueryState('array', queryTypes.array(queryTypes.integer)) // state is number[]
useQueryState('json', queryTypes.json<Point>()) // state is a Point

// Enums (string-based only)
enum Direction {
  up = 'UP',
  down = 'DOWN',
  left = 'LEFT',
  right = 'RIGHT'
}

const [direction, setDirection] = useQueryState(
  'direction',
  queryTypes
    .stringEnum<Direction>(Object.values(Direction)) // pass a list of allowed values
    .withDefault(Direction.up)
)

You may pass a custom set of parse and serialize functions:

import { useQueryState } from 'next-usequerystate'

export default () => {
  const [hex, setHex] = useQueryState('hex', {
    // TypeScript will automatically infer it's a number
    // based on what `parse` returns.
    parse: (query: string) => parseInt(query, 16),
    serialize: value => value.toString(16)
  })
}

Example: simple counter stored in the URL:

import { useQueryState, queryTypes } from 'next-usequerystate'

export default () => {
  const [count, setCount] = useQueryState('count', queryTypes.integer)
  return (
    <>
      <pre>count: {count}</pre>
      <button onClick={() => setCount(0)}>Reset</button>
      <button onClick={() => setCount(c => c ?? 0 + 1)}>+</button>
      <button onClick={() => setCount(c => c ?? 0 - 1)}>-</button>
      <button onClick={() => setCount(null)}>Clear</button>
    </>
  )
}

When the query string is not present in the URL, the default behaviour is to return null as state.

As you saw in the previous example, it makes state updating and UI rendering tedious.

You can specify a default value to be returned in this case:

const [count, setCount] = useQueryState(
  'count',
  queryTypes.integer.withDefault(0)
)

const increment = () => setCount(c => c + 1) // c will never be null
const decrement = () => setCount(c => c - 1) // c will never be null
const clearCount = () => setCount(null) // Remove query from the URL

Note: the default value is internal to React, it will not be written to the URL.

Setting the state to null will remove the key in the query string and set the state to the default value.

By default, state updates are done by replacing the current history entry with the updated query when state changes.

You can see this as a sort of git squash, where all state-changing operations are merged into a single history value.

You can also opt-in to push a new history item for each state change, per key, which will let you use the Back button to navigate state updates:

// Default: replace current history with new state
useQueryState('foo', { history: 'replace' })

// Append state changes to history:
useQueryState('foo', { history: 'push' })

Any other value for the history option will fallback to the default.

Because the Next.js router has asynchronous methods, if you want to do multiple query updates in one go, you'll have to await them, otherwise the latter will overwrite the updates of the former:

const MultipleQueriesDemo = () => {
  const [lat, setLat] = useQueryState('lat', queryTypes.float)
  const [lng, setLng] = useQueryState('lng', queryTypes.float)
  const randomCoordinates = React.useCallback(async () => {
    await setLat(Math.random() * 180 - 90)
    await setLng(Math.random() * 360 - 180)
  }, [])
}

For query keys that should always move together, you can use useQueryStates with an object containing each key's type:

import { useQueryStates, queryTypes } from 'next-usequerystate'

const [coordinates, setCoordinates] = useQueryStates(
  {
    lat: queryTypes.float.withDefault(45.18),
    lng: queryTypes.float.withDefault(5.72)
  },
  {
    history: 'push'
  }
)

const { lat, lng } = coordinates

// Set all (or a subset of) the keys in one go:
await setCoordinates({
  lat: Math.random() * 180 - 90,
  lng: Math.random() * 360 - 180
})

By default Next.js will scroll to the top of the page when changing things in the URL.

To prevent this, router.push() and router.replace() have a third optional parameter to control transitions, which can be passed on the state setter here:

const [name, setName] = useQueryState('name')

setName('Foo', {
  scroll: false,
  shallow: true // Don't run getStaticProps / getServerSideProps / getInitialProps
})

Because the Next.js router is not available in an SSR context, this hook will always return null (or the default value if supplied) on SSR/SSG.

MIT

• Made with ❤️ by François Best

Using this package at work ? Sponsor me to help with support and maintenance.