Cart App

Shopping cart, checkout, and order management service for the Rose Ash cooperative.

Architecture

One of four Quart microservices sharing a single PostgreSQL database:

App	Port	Domain
blog (coop)	8000	Auth, blog, admin, menus, snippets
market	8001	Product browsing, Suma scraping
cart	8002	Shopping cart, checkout, orders
events	8003	Calendars, bookings, tickets

Structure

app.py                  # Application factory (create_base_app + blueprints)
path_setup.py           # Adds project root + app dir to sys.path
config/app-config.yaml  # App URLs, SumUp config
models/                 # Cart-domain models
  order.py              #   Order, OrderItem
  page_config.py        #   PageConfig (per-page SumUp credentials)
bp/
  cart/                 # Cart blueprint
    global_routes.py    #   Add to cart, checkout, webhooks, return page
    page_routes.py      #   Page-scoped cart and checkout
    overview_routes.py  #   Cart overview / summary page
    api.py              #   Internal API (/internal/cart/summary)
    services/           #   Business logic
      checkout.py       #     Order creation, SumUp integration
      check_sumup_status.py  #  Payment status polling
      calendar_cart.py  #     Calendar entry cart queries
      page_cart.py      #     Page-scoped cart queries
      get_cart.py       #     Cart item queries
      identity.py       #     Cart identity (user_id / session_id)
      total.py          #     Price calculations
      clear_cart_for_order.py  # Soft-delete cart after checkout
  order/                # Single order detail view
  orders/               # Order listing view
templates/              # Jinja2 templates
entrypoint.sh           # Docker entrypoint
Dockerfile
shared/                 # Submodule → git.rose-ash.com/coop/shared.git
glue/                   # Submodule → git.rose-ash.com/coop/glue.git

Cross-App Integration

• Internal API: GET /internal/cart/summary returns cart count + total for the current session/user. Called by blog and market context processors.
• Calendar entries: Checkout marks CalendarEntries (events domain) as "ordered" via glue/services/order_lifecycle.py — not by direct model write.
• Payment confirmation: When SumUp payment confirms, entries are marked "provisional" via the same glue service.
• Domain events: Emits order.created and order.paid events for observability.
• Login adoption: Anonymous cart/entries are adopted when user.logged_in event fires (handled by glue/handlers/login_handlers.py).

Checkout Flow

1. User clicks "Checkout"
2. create_order_from_cart() creates Order + OrderItems
3. glue: claim_entries_for_order() marks CalendarEntries as "ordered"
4. emit: order.created event
5. SumUp hosted checkout created, user redirected
6. SumUp webhook / return page triggers check_sumup_status()
7. If PAID: glue: confirm_entries_for_order(), emit: order.paid

Running

export DATABASE_URL_ASYNC=postgresql+asyncpg://user:pass@localhost/coop
export REDIS_URL=redis://localhost:6379/0
export SECRET_KEY=your-secret-key

hypercorn app:app --reload --bind 0.0.0.0:8002

Docker

docker build -t cart .
docker run -p 8002:8000 --env-file .env cart