Query Retries

When a useQuery query fails (the query function throws an error), Svelte Query will automatically retry the query if that query's request has not reached the max number of consecutive retries (defaults to 3) or a function is provided to determine if a retry is allowed.

You can configure retries both on a global level and an individual query level.

• Setting retry = false will disable retries.
• Setting retry = 6 will retry failing requests 6 times before showing the final error thrown by the function.
• Setting retry = true will infinitely retry failing requests.
• Setting retry = (failureCount, error) => ... allows for custom logic based on why the request failed.

1 import { useQuery } from '@sveltestack/svelte-query'
2 
3 // Make a specific query retry a certain number of times
4 const queryResult = useQuery(['todos', 1], fetchTodoListPage, {
5   retry: 10, // Will retry failed requests 10 times before displaying an error
6 })

Retry Delay

By default, retries in Svelte Query do not happen immediately after a request fails. As is standard, a back-off delay is gradually applied to each retry attempt.

The default retryDelay is set to double (starting at 1000ms) with each attempt, but not exceed 30 seconds:

1 <script>
2 // Configure for all queries
3 import { QueryCache, QueryClient, QueryClientProvider } from '@sveltestack/svelte-query'
4 
5 const queryClient = new QueryClient({
6   defaultOptions: {
7     queries: {
8       retryDelay: attemptIndex => Math.min(1000 * 2 ** attemptIndex, 30000),
9     },
10   },
11 })
12 </script>
13 
14 <QueryClientProvider client={queryClient}>...</QueryClientProvider>

Though it is not recommended, you can obviously override the retryDelay function/integer in both the Provider and individual query options. If set to an integer instead of a function the delay will always be the same amount of time:

1 const queryResult = useQuery('todos', fetchTodoList, {
2   retryDelay: 1000, // Will always wait 1000ms to retry, regardless of how many retries
3 })