useMutation

1 const {
2   data,
3   error,
4   isError,
5   isIdle,
6   isLoading,
7   isPaused,
8   isSuccess,
9   mutate,
10   mutateAsync,
11   reset,
12   status,
13 } = useMutation(mutationFn, {
14   mutationKey,
15   onError,
16   onMutate,
17   onSettled,
18   onSuccess,
19   useErrorBoundary,
20 })
21 
22 mutate(variables, {
23   onError,
24   onSettled,
25   onSuccess,
26 })

Options

• mutationFn: (variables: TVariables) => Promise<TData>
  • Required
  • A function that performs an asynchronous task and returns a promise.
  • variables is an object that mutate will pass to your mutationFn
• mutationKey: string
  • Optional
  • A mutation key can be set to inherit defaults set with queryClient.setMutationDefaults or to identify the mutation in the devtools.
• onMutate: (variables: TVariables) => Promise<TContext | void> | TContext | void
  • Optional
  • This function will fire before the mutation function is fired and is passed the same variables the mutation function would receive
  • Useful to perform optimistic updates to a resource in hopes that the mutation succeeds
  • The value returned from this function will be passed to both the onError and onSettled functions in the event of a mutation failure and can be useful for rolling back optimistic updates.
• onSuccess: (data: TData, variables: TVariables, context?: TContext) => Promise<void> | void
  • Optional
  • This function will fire when the mutation is successful and will be passed the mutation's result.
  • If a promise is returned, it will be awaited and resolved before proceeding
• onError: (err: TError, variables: TVariables, context?: TContext) => Promise<void> | void
  • Optional
  • This function will fire if the mutation encounters an error and will be passed the error.
  • If a promise is returned, it will be awaited and resolved before proceeding
• onSettled: (data: TData, error: TError, variables: TVariables, context?: TContext) => Promise<void> | void
  • Optional
  • This function will fire when the mutation is either successfully fetched or encounters an error and be passed either the data or error
  • If a promise is returned, it will be awaited and resolved before proceeding
• retry: boolean | number | (failureCount: number, error: TError) => boolean
  • If false, failed mutations will not retry by default.
  • If true, failed mutations will retry infinitely.
  • If set to an number, e.g. 3, failed mutations will retry until the failed mutations count meets that number.
• retryDelay: number | (retryAttempt: number, error: TError) => number
  • This function receives a retryAttempt integer and the actual Error and returns the delay to apply before the next attempt in milliseconds.
  • A function like attempt => Math.min(attempt > 1 ? 2 ** attempt * 1000 : 1000, 30 * 1000) applies exponential backoff.
  • A function like attempt => attempt * 1000 applies linear backoff.
• useErrorBoundary
  • Defaults to the global query config's useErrorBoundary value, which is false
  • Set this to true if you want mutation errors to be thrown in the render phase and propagate to the nearest error boundary

Returns

• mutate: (variables: TVariables, { onSuccess, onSettled, onError }) => void
  • The mutation function you can call with variables to trigger the mutation and optionally override options passed to useMutation.
  • variables: TVariables
    • Optional
    • The variables object to pass to the mutationFn.
  • Remaining options extend the same options described above in the useMutation hook.
  • If you make multiple requests, onSuccess will fire only after the latest call you've made.
• mutateAsync: (variables: TVariables, { onSuccess, onSettled, onError }) => Promise<TData>
  • Similar to mutate but returns a promise which can be awaited.
• status: string
  • Will be:
    • idle initial status prior to the mutation function executing.
    • loading if the mutation is currently executing.
    • error if the last mutation attempt resulted in an error.
    • success if the last mutation attempt was successful.
• isIdle, isLoading, isSuccess, isError: boolean variables derived from status
• data: undefined | unknown
  • Defaults to undefined
  • The last successfully resolved data for the query.
• error: null | TError
  • The error object for the query, if an error was encountered.
• reset: () => void
  • A function to clean the mutation internal state (i.e., it resets the mutation to its initial state).