Managing the client ID and client secret
Where to find the client ID and client secret, how to store them, regenerating the secret after a suspected leak, and running several environments.
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.
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.
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.
Rotating and safely storing secrets
Explains the rotation plan for safely operating ReceiptRoller client secrets and Webhook secrets, how to use the old/new parallel period, and best practices for storage.
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.
Obtaining and refreshing an access token
How to obtain and refresh access tokens (8 hours) and refresh tokens (30 days), how refresh tokens rotate, and when tokens stop working.
What is application registration
Explains the concept of ReceiptRoller application registration. Registering an app as an OAuth client issues a client ID, secret, and redirect URI, letting you start API and Webhook integrations.
Webhook is not being delivered
When a webhook does not arrive: narrow it down with a test send and the delivery log, then check the active flag, subscribed events, connection and signature.
Cannot obtain a token (authentication error)
How to narrow down a 400 or 401 from the token endpoint, with the fix for each error and error_description, including invalid_client and invalid_grant.
Your first API call: from app registration to listing transactions
Get a token with the OAuth authorization code flow and PKCE, confirm the business account, list its transactions, and refresh the token.
Setting the redirect URL
The role of the single redirect URI on a developer app, the exact-match rule, separating environments, changing it, and common errors.
Wallet App: Guide to Fetching a User's Receipts via OAuth
Explains how to fetch a user's Receipt Roller purchase receipts, with their consent, from a wallet-style app such as iOS, Android, or a LINE Mini App. Covers OAuth 2.0 authentication, the receipts API, and Webhook integration.
Monitoring and handling failures
Read a webhook's active flag, last delivery time and delivery log, notice when it has switched itself off, recover, and fill the gap from the API.
API Authentication Guide
How to authenticate with the OAuth 2.0 authorization code flow: authorize parameters, the consent screen, token exchange and revocation, errors and scopes.
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.