9.4 KiB
id, title
| id | title |
|---|---|
| QueryCache | QueryCache |
Defined in: packages/query-core/src/queryCache.ts:123
The QueryCache is the storage mechanism for TanStack Query. It stores all the data, meta
information, and state of the queries it contains.
Normally, you will not interact with the QueryCache directly and instead use a QueryClient
for a specific cache. You can subscribe to it (inherited from Subscribable) to be informed of
safe/known updates to the cache, such as queries being added, removed, or updated — updates made
outside of the cache's own tracked mechanisms (e.g. mutating a query's state object directly) do
not notify subscribers.
Example
const unsubscribe = queryCache.subscribe((event) => {
console.log(event.type, event.query)
})
Extends
Subscribable<QueryCacheListener>
Constructors
Constructor
new QueryCache(config): QueryCache;
Defined in: packages/query-core/src/queryCache.ts:126
Parameters
config
QueryCacheConfig = {}
Returns
QueryCache
Overrides
Subscribable<QueryCacheListener>.constructor
Properties
config
config: QueryCacheConfig = {};
Defined in: packages/query-core/src/queryCache.ts:126
listeners
protected listeners: Set<QueryCacheListener>;
Defined in: packages/query-core/src/subscribable.ts:2
Inherited from
Subscribable.listeners
Methods
build()
build<TQueryFnData, TError, TData, TQueryKey>(
client,
options,
state?): Query<TQueryFnData, TError, TData, TQueryKey>;
Defined in: packages/query-core/src/queryCache.ts:147
Returns the existing Query instance for the given options' queryKey/queryHash, or
builds and adds a new one to the cache if none exists yet. Used by framework adapters and
plugins (e.g. broadcast/persistence) that need to get-or-create a Query directly, bypassing
the reactive QueryObserver machinery.
Type Parameters
TQueryFnData
TQueryFnData = unknown
TError
TError = Error
TData
TData = TQueryFnData
TQueryKey
TQueryKey extends readonly unknown[] = readonly unknown[]
Parameters
client
options
WithRequired<QueryOptions<TQueryFnData, TError, TData, TQueryKey, never>, "queryKey">
state?
QueryState<TData, TError>
Returns
Query<TQueryFnData, TError, TData, TQueryKey>
Example
const queryCache = queryClient.getQueryCache()
const query = queryCache.build(queryClient, {
queryKey: ['posts'],
queryFn: fetchPosts,
})
clear()
clear(): void;
Defined in: packages/query-core/src/queryCache.ts:232
Removes all queries from the cache.
Returns
void
Example
const queryCache = queryClient.getQueryCache()
queryCache.clear()
find()
find<TQueryFnData, TError, TData>(filters):
| Query<TQueryFnData, TError, TData, readonly unknown[]>
| undefined;
Defined in: packages/query-core/src/queryCache.ts:299
A slightly more advanced method that can be used to get an existing query instance from the
cache. This instance not only contains all the state for the query, but all of the instances,
and underlying guts of the query as well. If the query does not exist, undefined is
returned.
This is not typically needed for most applications, but can come in handy when needing more
information about a query in rare scenarios (e.g. looking at query.state.dataUpdatedAt to
decide whether a query is fresh enough to be used as an initial value).
Type Parameters
TQueryFnData
TQueryFnData = unknown
TError
TError = Error
TData
TData = TQueryFnData
Parameters
filters
WithRequired<QueryFilters<readonly unknown[]>, "queryKey">
Returns
| Query<TQueryFnData, TError, TData, readonly unknown[]>
| undefined
See
Example
const queryCache = queryClient.getQueryCache()
const query = queryCache.find({ queryKey: ['posts'] })
findAll()
findAll(filters): Query<unknown, Error, unknown, readonly unknown[]>[];
Defined in: packages/query-core/src/queryCache.ts:324
An even more advanced method that can be used to get existing query instances from the cache that partially match a query key. If no queries match, an empty array is returned.
This is not typically needed for most applications, but can come in handy when needing more information about queries in rare scenarios.
Parameters
filters
QueryFilters<any> = {}
Returns
Query<unknown, Error, unknown, readonly unknown[]>[]
See
Example
const queryCache = queryClient.getQueryCache()
const queries = queryCache.findAll({ queryKey: ['posts'] })
get()
get<TQueryFnData, TError, TData, TQueryKey>(queryHash):
| Query<TQueryFnData, TError, TData, TQueryKey>
| undefined;
Defined in: packages/query-core/src/queryCache.ts:254
Returns the Query instance stored under the given queryHash, or undefined if none
exists. Unlike QueryCache#find, this looks up by the already-computed hash rather
than by QueryFilters. Used by plugins (e.g. broadcast/hydration) that already have a hash
to look up directly.
Type Parameters
TQueryFnData
TQueryFnData = unknown
TError
TError = Error
TData
TData = TQueryFnData
TQueryKey
TQueryKey extends readonly unknown[] = readonly unknown[]
Parameters
queryHash
string
Returns
| Query<TQueryFnData, TError, TData, TQueryKey>
| undefined
Example
const queryCache = queryClient.getQueryCache()
const queryHash = hashKey(['posts'])
const query = queryCache.get(queryHash)
getAll()
getAll(): Query<unknown, Error, unknown, readonly unknown[]>[];
Defined in: packages/query-core/src/queryCache.ts:277
Returns all queries within the cache.
Returns
Query<unknown, Error, unknown, readonly unknown[]>[]
Example
const queryCache = queryClient.getQueryCache()
const queries = queryCache.getAll()
hasListeners()
hasListeners(): boolean;
Defined in: packages/query-core/src/subscribable.ts:19
Returns
boolean
Inherited from
Subscribable.hasListeners
onSubscribe()
protected onSubscribe(): void;
Defined in: packages/query-core/src/subscribable.ts:23
Returns
void
Inherited from
Subscribable.onSubscribe
onUnsubscribe()
protected onUnsubscribe(): void;
Defined in: packages/query-core/src/subscribable.ts:27
Returns
void
Inherited from
Subscribable.onUnsubscribe
remove()
remove(query): void;
Defined in: packages/query-core/src/queryCache.ts:208
Destroys the given Query and removes it from the cache, notifying subscribers with a
'removed' event. A no-op if the query is no longer the one currently stored under its hash
(e.g. it was already replaced). Used by plugins (e.g. the broadcast client) that mirror
removals across QueryCache instances.
Parameters
query
Query<any, any, any, any>
Returns
void
Example
const queryCache = queryClient.getQueryCache()
const query = queryCache.find({ queryKey: ['posts'] })
if (query) {
queryCache.remove(query)
}
subscribe()
subscribe(listener): () => void;
Defined in: packages/query-core/src/subscribable.ts:8
Parameters
listener
QueryCacheListener
Returns
(): void;
Returns
void
Inherited from
Subscribable.subscribe