MutationCache is the storage for mutations.
Normally, you will not interact with the MutationCache directly and instead use the
Its available methods are:
onError?: (error: unknown, variables: unknown, context: unknown, mutation: Mutation) => void
onSuccess?: (data: unknown, variables: unknown, context: unknown, mutation: Mutation) => void
onMutate?: (variables: unknown, mutation: Mutation) => void
onMutate callbacks on the MutationCache can be used to handle these events on a global level. They are different to
defaultOptions provided to the QueryClient because:
defaultOptionscan be overridden by each Mutation - the global callbacks will always be called.
onMutatedoes not allow returning a context value.
getAll returns all mutations within the cache.
Note: This is not typically needed for most applications, but can come in handy when needing more information about a mutation in rare scenarios
subscribe method can be used to subscribe to the mutation cache as a whole and be informed of safe/known updates to the cache like mutation states changing or mutations being updated, added or removed.
callback: (mutation?: Mutation) => void
unsubscribe: Function => void
clear method can be used to clear the cache entirely and start fresh.