Receive new sales by webhook and post them to Slack
Register a receipt.created webhook, verify its signature and drop duplicates in Node.js, and post each new sale to a Slack channel.
Designing resends, ordering, and idempotency
What counts as success, the retry rules (1 min, 10 min, 1 h, four attempts), ordering and lost events, and dropping duplicates by X-RR-Delivery.
Signature verification and security
How X-RR-Signature is computed, verification code for Node.js, Python and C#, guarding against replays, and how to replace a webhook secret.
Rate limiting and throttling
Which ReceiptRoller API endpoints limit requests and by how much, what a 429 looks like, and how to pace and retry your client's calls.
Creating a new app
How to register a developer app in a business account: the fields, how the credentials are shown, what you can do afterwards, and common stumbling points.
Webhook overview
Which webhook events are actually sent, what the request and signature headers look like, how duplicates, order and lost events behave, and when to use the API.
How to register a Webhook
Register a webhook in the developer portal or through the API, choose events that are actually sent, run a test send, and change, pause or delete a webhook.