The digest engine is designed to streamline notifications by accumulating multiple trigger events into one coherent message before delivery to the subscriber. This function proves beneficial when a user needs to be alerted about numerous triggers, but it’s important to minimize the frequency of notifications. Novu automates this process, batching incoming trigger events according to a unique subscriberId. There is also the option to include a digestKey, providing additional control over event digestion workflows.

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Step Interface

const digestResult = await step.digest('digest-3-days', async () => {
  return {
	  unit: 'days', // 'seconds' | 'minutes' | 'hours' | 'days' | 'weeks' | 'months'
	  amount: 3, // the number of units to digest events for
	};
});

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Using the digested triggers

The digest function returns an array of triggers that have been digested. You can use this array to perform any necessary actions on the digested triggers. Like Sending and email, or updating a database. 
const digestResult = await step.digest('digest-3-days', async () => {
  return {
	  unit: 'days', // 'seconds' | 'minutes' | 'hours' | 'days' | 'weeks' | 'months'
	  amount: 3, // the number of units to digest events for
	};
});

await step.email('send-email', async () => {
  return {
    subject: 'Digest Email',
    body: `You have ${digestResult.events.length} new events`,
 };
});
The digest step returns an object with events array. Each event in the array has the following properties:
  • id - The job id of the digested event
  • time - The time when the event was triggered
  • payload - The original payload passed to the event