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createSubscriber

Create a type-safe event subscriber function. The event data type is automatically inferred from the event name, providing IDE autocomplete and compile-time type checking.

Import​

import { createSubscriber } from '@evershop/evershop/lib/event/subscriber';
import type { EventSubscriber } from '@evershop/evershop/lib/event/subscriber';

Syntax​

createSubscriber<T extends EventName>(
  eventName: T,
  handler: EventSubscriber<T>
): (data: EventDataRegistry[T]) => Promise<void>

Parameters​

eventName

Type: T extends EventName

The name of the event to subscribe to. Must be a registered event name.

handler

Type: EventSubscriber<T>

The handler function. Receives the event data with the correct type based on the event name.

Return Value​

Returns an async function suitable for use as a subscriber default export.

Examples​

Type-Safe Product Subscriber​

extensions/my-ext/src/subscribers/product_created/syncCatalog.ts
import { createSubscriber } from '@evershop/evershop/lib/event/subscriber';

export default createSubscriber('product_created', async (data) => {
  // 'data' is automatically typed as ProductRow
  const sku = data.sku;
  const price = data.price;
  await syncToExternalCatalog(sku, price);
});

Using the EventSubscriber Type Directly​

extensions/my-ext/src/subscribers/order_placed/sendEmail.ts
import type { EventSubscriber } from '@evershop/evershop/lib/event/subscriber';

const handler: EventSubscriber<'order_placed'> = async (data) => {
  // 'data' is typed as OrderRow
  await sendOrderConfirmation(data.customer_email, data.order_number);
};

export default handler;

Notes​

  • Subscriber files must be placed in subscribers/{eventName}/ directory
  • Each file must have a default export (the handler function)
  • Subscribers execute asynchronously in a separate child process
  • See the Events and Subscribers guide for the full list of available events

See Also​