Polling

Polling Overview

Polling gives you the ability to have a 'real-time' effect by causing a query to run at a specified interval. To enable polling for a query, pass a pollingInterval to the useQuery hook or action creator with an interval in milliseconds:

tip

Polling additionally has the ability to skip sending requests while the window is out of focus. To enable this behavior, pass skipPollingIfUnfocused: true to the useQuery hook or action creator.

Note: skipPollingIfUnfocused requires setupListeners to have been called.

src/Pokemon.tsx

import * as React from 'react'
import { useGetPokemonByNameQuery } from './services/pokemon'

export const Pokemon = ({ name }: { name: string }) => {
  // Automatically refetch every 3s unless the window is out of focus
  const { data, status, error, refetch } = useGetPokemonByNameQuery(name, {
    pollingInterval: 3000,
    skipPollingIfUnfocused: true,
  })

  return <div>{data}</div>
}

In an action creator without React Hooks:

const { data, status, error, refetch } = store.dispatch(
  endpoints.getCountById.initiate(id, {
    subscriptionOptions: { pollingInterval: 3000 },
  }),
)

Polling Without React Hooks

If you use polling without the convenience of React Hooks, you will need to manually call updateSubscriptionOptions on the promise ref to update the interval. This approach varies by framework but is possible everywhere. See the Svelte Example for one possibility, and the Usage Without React Hooks page for more details on working with subscriptions manually.

queryRef.updateSubscriptionOptions({ pollingInterval: 0 })

Polling Example