createWebStoragePersister

Installation

This utility comes packaged with react-query and is available under the react-query/createWebStoragePersister import.

Usage

• Import the createWebStoragePersister function
• Create a new webStoragePersister
• Pass it to the persistQueryClient function

1 import { persistQueryClient } from 'react-query/persistQueryClient'
2 import { createWebStoragePersister } from 'react-query/createWebStoragePersister'
3 
4 const queryClient = new QueryClient({
5   defaultOptions: {
6     queries: {
7       cacheTime: 1000 * 60 * 60 * 24, // 24 hours
8     },
9   },
10 })
11 
12 const localStoragePersister = createWebStoragePersister({ storage: window.localStorage })
13 // const sessionStoragePersister = createWebStoragePersister({ storage: window.sessionStorage })
14 
15 persistQueryClient({
16   queryClient,
17   persister: localStoragePersister,
18 })

Retries

Persistence can fail, e.g. if the size exceeds the available space on the storage. Errors can be handled gracefully by providing a retry function to the persister.

The retry function receives the persistedClient it tried to save, as well as the error and the errorCount as input. It is expected to return a new PersistedClient, with which it tries to persist again. If undefined is returned, there will be no further attempt to persist.

1 export type PersistRetryer = (props: {
2   persistedClient: PersistedClient
3   error: Error
4   errorCount: number
5 }) => PersistedClient | undefined

Predefined strategies

Per default, no retry will occur. You can use one of the predefined strategies to handle retries. They can be imported from 'react-query/persistQueryClient':

• removeOldestQuery
  • will return a new PersistedClient with the oldest query removed.

1 const localStoragePersister = createWebStoragePersister({
2   storage: window.localStorage,
3   retry: removeOldestQuery
4 })

API

createWebStoragePersister

Call this function to create a webStoragePersister that you can use later with persistQueryClient.

 createWebStoragePersister(options: CreateWebStoragePersisterOptions)

Options

1 interface CreateWebStoragePersisterOptions {
2   /** The storage client used for setting an retrieving items from cache (window.localStorage or window.sessionStorage) */
3   storage: Storage
4   /** The key to use when storing the cache */
5   key?: string
6   /** To avoid spamming,
7    * pass a time in ms to throttle saving the cache to disk */
8   throttleTime?: number
9   /** How to serialize the data to storage */
10   serialize?: (client: PersistedClient) => string
11   /** How to deserialize the data from storage */
12   deserialize?: (cachedString: string) => PersistedClient
13   /** How to retry persistence on error **/
14   retry?: PersistRetryer
15 }

The default options are:

1 {
2   key = `REACT_QUERY_OFFLINE_CACHE`,
3   throttleTime = 1000,
4   serialize = JSON.stringify,
5   deserialize = JSON.parse,
6 }

serialize and deserialize options

There is a limit to the amount of data which can be stored in localStorage. If you need to store more data in localStorage, you can override the serialize and deserialize functions to compress and decrompress the data using a library like lz-string.

1 import { QueryClient } from 'react-query';
2 import { persistQueryClient } from 'react-query/persistQueryClient'
3 import { createWebStoragePersister } from 'react-query/createWebStoragePersister'
4 
5 import { compress, decompress } from 'lz-string';
6 
7 const queryClient = new QueryClient({ defaultOptions: { queries: { staleTime: Infinity } } });
8 
9 persistQueryClient({
10   queryClient: connectionsQueryClient,
11   persistor: createWebStoragePersister({
12     storage: window.localStorage,
13     serialize: data => compress(JSON.stringify(data)),
14     deserialize: data => JSON.parse(decompress(data)),
15   }),
16   maxAge: Infinity,
17 });