Node.js - bucket.on()

Create a new bucket notification trigger when certain files are created or deleted.

import { bucket } from '@nitric/sdk';

const assets = bucket('assets');

const accessibleAssets = bucket('assets').for('reading');

// The request will contain the name of the file `key` and the type of event `type`
assets.on('delete', '*', (ctx) => {
  console.log(`A file named ${ctx.req.key} was deleted`);

assets.on('write', '/images/cat', (ctx) => {
  console.log('A cat image was written');

// If `on` is called with a permissioned bucket, a file will also be provided with the request
accessibleAssets.on('write', '/images/dog', async (ctx) => {
  const dogImage = await;



notification type required write or delete

The notification type for a triggered event, either on a file write or a file delete.

notification prefix filter required string

The file prefix filter that must match for a triggered event. If multiple filters overlap across notifications then an error will be thrown when registering the resource.

middleware required BucketNotificationMiddleware or BucketNotificationMiddleware[]

The middleware (code) to be triggered by the bucket notification being triggered.

Available trigger types:


Run when a file in the bucket is created using: file.write()


Run when a file in the bucket is deleted using: file.delete()

Trigger type cloud mapping