PhoenixKit V33 Migration: Payment Providers and Subscriptions

This migration introduces payment provider integrations (Stripe, PayPal, Razorpay) and the subscription system with internal billing control.

Design Philosophy

PhoenixKit uses Internal Subscription Control - subscriptions are managed in our database as the source of truth, not by payment providers. This approach:

• Allows using providers without subscription API support
• Gives full control over subscription lifecycle
• Enables pause, resume, proration calculations
• Supports multiple providers for the same subscription

Changes

Payment Methods Table (phoenix_kit_payment_methods)

• Saved payment methods (cards, wallets) for recurring billing
• Tokenized data from providers (no raw card data stored)
• Display info for user (last4, brand, expiration)

Subscription Plans Table (phoenix_kit_subscription_plans)

• Subscription pricing plans
• Interval configuration (day/week/month/year)
• Trial period support
• Feature list (JSONB)

Subscriptions Table (phoenix_kit_subscriptions)

• User subscriptions (master record)
• Status tracking with grace period and dunning
• Billing cycle management
• Payment method association

Payment Provider Configs Table (phoenix_kit_payment_provider_configs)

• Provider credentials (encrypted)
• Webhook secrets
• Test/Live mode configuration

Webhook Events Table (phoenix_kit_webhook_events)

• Webhook event logging for idempotency
• Event processing status tracking
• Retry count for failed events

Modifications to Existing Tables

• Orders: checkout session fields
• Invoices: subscription reference

Settings Seeds

• Provider enable/disable settings
• Subscription grace period configuration
• Dunning retry configuration