AlgoKit Subscriber TypeScript

Installation

npm

bash npm install @algorandfoundation/algokit-subscriber

pnpm

bash pnpm add @algorandfoundation/algokit-subscriber

yarn

bash yarn add @algorandfoundation/algokit-subscriber

Quick Example

import { AlgorandClient } from '@algorandfoundation/algokit-utils';
import { AlgorandSubscriber } from '@algorandfoundation/algokit-subscriber';
import { TransactionType } from '@algorandfoundation/algokit-utils/transact';

const algorand = AlgorandClient.testNet();

const subscriber = new AlgorandSubscriber(
  {
    filters: [
      {
        name: 'filter1',
        filter: {
          type: TransactionType.pay,
          sender: 'ABC...',
        },
      },
    ],
    watermarkPersistence: {
      get: async () => 0n,
      set: async watermark => {
        /* save watermark */
      },
    },
  },
  algorand.client.algod,
  algorand.client.indexer,
);

// Set up subscription(s)
subscriber.on('filter1', async transaction => {
  // ...
});

// Set up error handling
subscriber.onError(e => {
  // ...
});

// Either: Start the subscriber (if in long-running process)
subscriber.start();

// OR: Poll the subscriber (if in cron job / periodic lambda)
subscriber.pollOnce();

Features

Real-time Subscriptions

Subscribe to transactions at the tip of the chain with low-latency processing.

Indexing & Catchup

Build indexes from the beginning of the chain with fast indexer catchup.

ARC-28 Events

Subscribe to and process ARC-28 events from smart contract calls.

Resilient Watermarking

Persist watermarks for reliable at-least-once delivery across outages.