Alby as a Fallback Payment Option for Rate Limiting

[kouloumos]

We've integrated an L402 middleware in our server to manage rate limits on user requests effectively. When users hit this limit, they're prompted to make a payment to continue accessing the app, with payments processed through the Lightning Network to our node. However, this system faces a potential challenge if our Lightning node encounters issues, disrupting the user experience.

To ensure uninterrupted service, we can add a fallback payment option. One solution is to utilize Alby, a custodial service that offers a straightforward invoices API, somewhat similar to the one used for LND nodes. While this introduces the downside of being custodial, its ease of integration and reliability make it an attractive option for maintaining our service's accessibility during node outages.

Implementation Considerations:

• API Adjustments: Integrating Alby as a fallback will require some modifications to our current setup to accommodate differences in their invoices API. This entails reviewing and adjusting our payment processing flow to ensure compatibility.
• User Experience: We should make this transition seamless for the user, automatically switching to Alby's service if our Lightning node is not available.

This fallback approach is designed as a quick and effective solution to keep our service running smoothly, ensuring users can continue to use the app without interruption, even if our primary Lightning node payment system is down.