QueryClient

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QueryClient #

The QueryClient can be used to interact with a cache:

 1import { QueryClient } from '@tanstack/react-query'
 2
 3const queryClient = new QueryClient({
 4  defaultOptions: {
 5    queries: {
 6      staleTime: Infinity,
 7    },
 8  },
 9})
10
11await queryClient.prefetchQuery({ queryKey: ['posts'], queryFn: fetchPosts })

Its available methods are:

Options

queryClient.fetchQuery #

fetchQuery is an asynchronous method that can be used to fetch and cache a query. It will either resolve with the data or throw with the error. Use the prefetchQuery method if you just want to fetch a query without needing the result.

If the query exists and the data is not invalidated or older than the given staleTime, then the data from the cache will be returned. Otherwise it will try to fetch the latest data.

The difference between using fetchQuery and setQueryData is that fetchQuery is async and will ensure that duplicate requests for this query are not created with useQuery instances for the same query are rendered while the data is fetching.

1try {
2  const data = await queryClient.fetchQuery({ queryKey, queryFn })
3} catch (error) {
4  console.log(error)
5}

Specify a staleTime to only fetch when the data is older than a certain amount of time:

1try {
2  const data = await queryClient.fetchQuery({
3    queryKey,
4    queryFn,
5    staleTime: 10000,
6  })
7} catch (error) {
8  console.log(error)
9}

Options

The options for fetchQuery are exactly the same as those of useQuery, except the following: enabled, refetchInterval, refetchIntervalInBackground, refetchOnWindowFocus, refetchOnReconnect, refetchOnMount, notifyOnChangeProps, throwOnError, select, suspense, placeholderData; which are strictly for useQuery and useInfiniteQuery. You can check the source code for more clarity.

Returns

queryClient.fetchInfiniteQuery #

fetchInfiniteQuery is similar to fetchQuery but can be used to fetch and cache an infinite query.

1try {
2  const data = await queryClient.fetchInfiniteQuery({ queryKey, queryFn })
3  console.log(data.pages)
4} catch (error) {
5  console.log(error)
6}

Options

The options for fetchInfiniteQuery are exactly the same as those of fetchQuery.

Returns

queryClient.prefetchQuery #

prefetchQuery is an asynchronous method that can be used to prefetch a query before it is needed or rendered with useQuery and friends. The method works the same as fetchQuery except that it will not throw or return any data.

1await queryClient.prefetchQuery({ queryKey, queryFn })

You can even use it with a default queryFn in your config!

1await queryClient.prefetchQuery({ queryKey })

Options

The options for prefetchQuery are exactly the same as those of fetchQuery.

Returns

queryClient.prefetchInfiniteQuery #

prefetchInfiniteQuery is similar to prefetchQuery but can be used to prefetch and cache an infinite query.

1await queryClient.prefetchInfiniteQuery({ queryKey, queryFn })

Options

The options for prefetchInfiniteQuery are exactly the same as those of fetchQuery.

Returns

queryClient.getQueryData #

getQueryData is a synchronous function that can be used to get an existing query's cached data. If the query does not exist, undefined will be returned.

1const data = queryClient.getQueryData(queryKey)

Options

Returns

queryClient.ensureQueryData #

ensureQueryData is an asynchronous function that can be used to get an existing query's cached data. If the query does not exist, queryClient.fetchQuery will be called and its results returned.

1const data = await queryClient.ensureQueryData({ queryKey, queryFn })

Options

Returns

queryClient.getQueriesData #

getQueriesData is a synchronous function that can be used to get the cached data of multiple queries. Only queries that match the passed queryKey or queryFilter will be returned. If there are no matching queries, an empty array will be returned.

1const data = queryClient.getQueriesData(filters)

Options

Returns

Caveats

Because the returned data in each tuple can be of varying structures (i.e. using a filter to return "active" queries can return different data types), the TData generic defaults to unknown. If you provide a more specific type to TData it is assumed that you are certain each tuple's data entry is all the same type.

This distinction is more a "convenience" for ts devs that know which structure will be returned.

queryClient.setQueryData #

setQueryData is a synchronous function that can be used to immediately update a query's cached data. If the query does not exist, it will be created. If the query is not utilized by a query hook in the default gcTime of 5 minutes, the query will be garbage collected. To update multiple queries at once and match query keys partially, you need to use queryClient.setQueriesData instead.

The difference between using setQueryData and fetchQuery is that setQueryData is sync and assumes that you already synchronously have the data available. If you need to fetch the data asynchronously, it's suggested that you either refetch the query key or use fetchQuery to handle the asynchronous fetch.

1queryClient.setQueryData(queryKey, updater)

Options

Using an updater value

1setQueryData(queryKey, newData)

If the value is undefined, the query data is not updated.

Using an updater function

For convenience in syntax, you can also pass an updater function which receives the current data value and returns the new one:

1setQueryData(queryKey, (oldData) => newData)

If the updater function returns undefined, the query data will not be updated. If the updater function receives undefined as input, you can return undefined to bail out of the update and thus not create a new cache entry.

Immutability

Updates via setQueryData must be performed in an immutable way. DO NOT attempt to write directly to the cache by mutating oldData or data that you retrieved via getQueryData in place.

queryClient.getQueryState #

getQueryState is a synchronous function that can be used to get an existing query's state. If the query does not exist, undefined will be returned.

1const state = queryClient.getQueryState(queryKey)
2console.log(state.dataUpdatedAt)

Options

queryClient.setQueriesData #

setQueriesData is a synchronous function that can be used to immediately update cached data of multiple queries by using filter function or partially matching the query key. Only queries that match the passed queryKey or queryFilter will be updated - no new cache entries will be created. Under the hood, setQueryData is called for each existing query.

1queryClient.setQueriesData(filters, updater)

Options

queryClient.invalidateQueries #

The invalidateQueries method can be used to invalidate and refetch single or multiple queries in the cache based on their query keys or any other functionally accessible property/state of the query. By default, all matching queries are immediately marked as invalid and active queries are refetched in the background.

1await queryClient.invalidateQueries(
2  {
3    queryKey: ['posts'],
4    exact,
5    refetchType: 'active',
6  },
7  { throwOnError, cancelRefetch },
8)

Options

queryClient.refetchQueries #

The refetchQueries method can be used to refetch queries based on certain conditions.

Examples:

 1// refetch all queries:
 2await queryClient.refetchQueries()
 3
 4// refetch all stale queries:
 5await queryClient.refetchQueries({ stale: true })
 6
 7// refetch all active queries partially matching a query key:
 8await queryClient.refetchQueries({ queryKey: ['posts'], type: 'active' })
 9
10// refetch all active queries exactly matching a query key:
11await queryClient.refetchQueries({
12  queryKey: ['posts', 1],
13  type: 'active',
14  exact: true,
15})

Options

Returns

This function returns a promise that will resolve when all of the queries are done being refetched. By default, it will not throw an error if any of those queries refetches fail, but this can be configured by setting the throwOnError option to true

queryClient.cancelQueries #

The cancelQueries method can be used to cancel outgoing queries based on their query keys or any other functionally accessible property/state of the query.

This is most useful when performing optimistic updates since you will likely need to cancel any outgoing query refetches so they don't clobber your optimistic update when they resolve.

1await queryClient.cancelQueries({ queryKey: ['posts'], exact: true })

Options

Returns

This method does not return anything

queryClient.removeQueries #

The removeQueries method can be used to remove queries from the cache based on their query keys or any other functionally accessible property/state of the query.

1queryClient.removeQueries({ queryKey, exact: true })

Options

Returns

This method does not return anything

queryClient.resetQueries #

The resetQueries method can be used to reset queries in the cache to their initial state based on their query keys or any other functionally accessible property/state of the query.

This will notify subscribers — unlike clear, which removes all subscribers — and reset the query to its pre-loaded state — unlike invalidateQueries. If a query has initialData, the query's data will be reset to that. If a query is active, it will be refetched.

1queryClient.resetQueries({ queryKey, exact: true })

Options

Returns

This method returns a promise that resolves when all active queries have been refetched.

queryClient.isFetching #

This isFetching method returns an integer representing how many queries, if any, in the cache are currently fetching (including background-fetching, loading new pages, or loading more infinite query results)

1if (queryClient.isFetching()) {
2  console.log('At least one query is fetching!')
3}

TanStack Query also exports a handy useIsFetching hook that will let you subscribe to this state in your components without creating a manual subscription to the query cache.

Options

Returns

This method returns the number of fetching queries.

queryClient.isMutating #

This isMutating method returns an integer representing how many mutations, if any, in the cache are currently fetching.

1if (queryClient.isMutating()) {
2  console.log('At least one mutation is fetching!')
3}

TanStack Query also exports a handy useIsMutating hook that will let you subscribe to this state in your components without creating a manual subscription to the mutation cache.

Options

Returns

This method returns the number of fetching mutations.

queryClient.getDefaultOptions #

The getDefaultOptions method returns the default options which have been set when creating the client or with setDefaultOptions.

1const defaultOptions = queryClient.getDefaultOptions()

queryClient.setDefaultOptions #

The setDefaultOptions method can be used to dynamically set the default options for this queryClient. Previously defined default options will be overwritten.

1queryClient.setDefaultOptions({
2  queries: {
3    staleTime: Infinity,
4  },
5})

queryClient.getQueryDefaults #

The getQueryDefaults method returns the default options which have been set for specific queries:

1const defaultOptions = queryClient.getQueryDefaults(['posts'])

Note that if several query defaults match the given query key, the first matching one is returned. This could lead to unexpected behaviours. See setQueryDefaults.

queryClient.setQueryDefaults #

setQueryDefaults can be used to set default options for specific queries:

1queryClient.setQueryDefaults(['posts'], { queryFn: fetchPosts })
2
3function Component() {
4  const { data } = useQuery({ queryKey: ['posts'] })
5}

Options

As stated in getQueryDefaults, the order of registration of query defaults does matter. Since the first matching defaults are returned by getQueryDefaults, the registration should be made in the following order: from the least generic key to the most generic one. This way, in case of specific key, the first matching one would be the expected one.

queryClient.getMutationDefaults #

The getMutationDefaults method returns the default options which have been set for specific mutations:

1const defaultOptions = queryClient.getMutationDefaults(['addPost'])

queryClient.setMutationDefaults #

setMutationDefaults can be used to set default options for specific mutations:

1queryClient.setMutationDefaults(['addPost'], { mutationFn: addPost })
2
3function Component() {
4  const { data } = useMutation({ mutationKey: ['addPost'] })
5}

Options

Similar to setQueryDefaults, the order of registration does matter here.

queryClient.getQueryCache #

The getQueryCache method returns the query cache this client is connected to.

1const queryCache = queryClient.getQueryCache()

queryClient.getMutationCache #

The getMutationCache method returns the mutation cache this client is connected to.

1const mutationCache = queryClient.getMutationCache()

queryClient.clear #

The clear method clears all connected caches.

1queryClient.clear()

queryClient.resumePausedMutations #

Can be used to resume mutations that have been paused because there was no network connection.

1queryClient.resumePausedMutations()