payments

Stripe-based subscription management with a tier system (data, reader, premium), invoice generation, Lexoffice bookkeeping sync, guest subscriptions with access tokens, identity event tracking, and webhook idempotency.

Models

Model	Description
SubscriptionTier	Tier definitions with dual Stripe price IDs (test/live) and feature flags
Invoice	Generated PDF invoices with email sending + Lexoffice upload tracking
Customer	Stripe customer → Django user one-to-one link
Subscription	Active or historical Stripe subscription for a registered user
GuestSubscription	Subscription for non-registered users (email + access token)
StripeCheckoutEvent	Idempotency log preventing duplicate webhook processing
IdentityEvent	Audit log for auth events (login, signup, email claim, etc.)

URL Routes

Path	View	Description
/payments/config/	stripe_config	Returns Stripe publishable key
/payments/checkout/session/	checkout_session_view	Legacy subscription checkout
/payments/checkout/webhook/	checkout_webhook_view	Stripe webhook receiver
/payments/checkout/success/	success	Post-checkout success page
/payments/checkout/canceled/	cancel	Cancellation page
/payments/stripe_customer_portal/	portal redirect	Redirect to Stripe billing portal
/payments/tier/pricing/	tier_pricing	GET available tiers with pricing
/payments/tier/checkout/	tier_checkout_session	POST create tier checkout session
/payments/manage-tier/	manage_tier_subscription	Manage subscription (token or auth)

Management Commands

Command	Description
backfill_user_links	Link guest purchases/subscriptions to users by matching email
identity_overview	Report on identity system events and counts

Subscription Tiers

graph LR DATA[data tier] -->|includes_data| DP[Data Products] READER[reader tier] -->|includes_reading| BLOG[Blog Posts] READER -->|includes_data| DP PREMIUM[premium tier] -->|includes_reading| BLOG PREMIUM -->|includes_data| DP PREMIUM -->|includes_ebooks| EBOOKS[eBook Downloads]

Webhook Flow

sequenceDiagram participant Stripe participant Webhook as checkout_webhook_view participant Events as StripeCheckoutEvent participant Invoice as Invoice Generator Stripe->>Webhook: POST event Webhook->>Events: Check event_id exists? alt Already processed Events-->>Webhook: 200 OK (skip) else New event Webhook->>Events: Create idempotency record Webhook->>Invoice: Generate PDF, email, Lexoffice Events-->>Webhook: 200 OK end

Key Design Decisions

• Dual Stripe price IDs (stripe_price_id_test / stripe_price_id_live) on SubscriptionTier allow seamless switching between Stripe test and live mode via a settings flag.

• Guest subscriptions use email + access_token for access without requiring registration.

• StripeCheckoutEvent provides webhook idempotency — every event is checked by event_id before processing to prevent duplicate invoice generation.

• IdentityEvent is append-only, capturing the full identity lifecycle (signup → email claim → account link → login).

• Webhook URL is mounted outside i18n_patterns at a fixed path so Stripe can always reach it regardless of language prefix.