FeaturesInngest FunctionsErrors & Retries

Failure handlers TypeScript only

If your function exhausts all of its retries, it will be marked as "Failed." You can handle this circumstance by either providing an onFailure/on_failure handler when defining your function, or by listening for the inngest/function.failed system event.

The first approach is function-specific, while the second covers all function failures in a given Inngest environment.

Examples

The example below checks if a user's subscription is valid a total of six times. If you can't check the subscription after all retries, you'll unsubscribe the user:

/* Option 1: give the inngest function an `onFailure` handler. */
inngest.createFunction(
  {
    id: "update-subscription",
    retries: 5,
    onFailure: async ({ event, error }) => {
      // if the subscription check fails after all retries, unsubscribe the user
      await unsubscribeUser(event.data.userId);
    },
  },
  { event: "user/subscription.check" },
  async ({ event }) => { /* ... */ },
);
/* Option 2: Listens for the [`inngest/function.failed`](/docs/reference/functions/handling-failures#the-inngest-function-failed-event) system event to catch all failures in the inngest environment*/
inngest.createFunction(
  { id: "handle-any-fn-failure" },
  { event: "inngest/function.failed" },
  async ({ event }) => { /* ... */ },
);

To handle cancelled function runs, checkout out this example that uses the inngest/function.cancelled system event.