dehydrate

function dehydrate(client: QueryClient, options?: DehydrateOptions): DehydratedState;

Defined in: packages/query-core/src/hydration.ts:245

Dehydrates a QueryClient's cache (queries and mutations) into a plain, serializable DehydratedState, typically to embed in server-rendered markup and later restore into a client-side QueryClient via hydrate. Which queries/mutations are included, and how their data/errors are transformed, is controlled by options, falling back to the client's dehydrate default options, and finally to defaultShouldDehydrateQuery / defaultShouldDehydrateMutation.

Parameters

client

QueryClient

The client whose cache is dehydrated.

options?

DehydrateOptions = {}

Controls which queries and mutations are included and how their data and errors are transformed. Each option falls back to the client's defaultOptions.dehydrate.

`options` properties

Property	Type	Description
`serializeData?`	`TransformerFn`	Transforms a query's `data` before it is dehydrated. Useful for non-JSON-serializable data.
`shouldDehydrateMutation?`	(`mutation`: `Mutation`) => `boolean`	Predicate to decide whether a given `Mutation` should be dehydrated. Defaults to `defaultShouldDehydrateMutation`.
`shouldDehydrateQuery?`	(`query`: `Query`) => `boolean`	Predicate to decide whether a given `Query` should be dehydrated. Defaults to `defaultShouldDehydrateQuery`.
`shouldRedactErrors?`	(`error`: `unknown`) => `boolean`	Predicate to decide whether a query's error should be redacted before dehydration. Errors are redacted (replaced with a generic `Error('redacted')`) unless this function is provided and returns `false` for the given error, in which case the original error is kept.

Returns

DehydratedState

The dehydrated state, with the included queries and mutations.

Result properties

Property	Type	Description
`mutations`	`DehydratedMutation`[]	The dehydrated mutations, by default only the paused ones.
`queries`	`DehydratedQuery`[]	The dehydrated queries, by default only the successful ones.

Example

const queryClient = new QueryClient()

await queryClient.prefetchQuery({
  queryKey: ['posts'],
  queryFn: getPosts,
})

const dehydratedState = dehydrate(queryClient)