# Restaurants: Product Catalog Using Django

## Summary
A product catalog blueprint for restaurants built with Django on Ample. Domain schema: 
- **menu_items** (sku, name, section, price, allergens, active): the menu as a SKU catalog;
- **stock_movements** (sku, delta, reason, moved_at): ingredient and prepared-item stock;
- **orders** (order_no, service_type, status, placed_at): dine-in, pickup, and delivery orders;
- **order_lines** (order_no, sku, qty, modifiers): order contents;
- **events** (seq, record_type, record_id, kind, at): application-owned history written in the same transaction.

Public information: menu with allergens and prices, locations, hours and reservations contact, catering information. Kept out of scope until handling is reviewed: customer contact and payment details, staff schedules. Allergen information must be kept accurate by the operator; nothing here validates food-safety claims. Technical basis verified on Django: an optimistic version check and an event row written in the same transaction, a stale update rejected, and a history query over the application-owned events (history=2 conflict=rejected).

## Infrastructure Requirements
- **Compute**: verified (Apps run in isolated x86_64 Firecracker microVMs that auto-pause when idle and wake on request; sizes are the priced VM sizes.)
- **Postgres**: verified (Managed PostgreSQL 16 runs in its own microVM and is auto-provisioned when an app needs a database and no DATABASE_URL is supplied.)
- **S3-compatible object storage**: verified (Buckets are S3-compatible with issued credentials; PutObject and GetObject are verified by canary. Other S3 operations are not verified.)

## Prerequisites
- A Django project (pip install into .ample/python from requirements.txt, then waitress serving project.wsgi from run.py reading PORT on the python-3.12 template)
- A PostgreSQL driver reading DATABASE_URL (auto-provisioned when omitted)
- Bucket credentials from `ample bucket create` passed as encrypted S3_* environment variables
- A review of which restaurants data classes may be handled at all; this blueprint models public information only

## Steps
1. **Model the Restaurants domain.** Create the tables menu_items, stock_movements, orders, order_lines, events. The menu as a SKU catalog lives in menu_items; keep the sensitive classes (customer contact and payment details, staff schedules) out of this schema.
2. **Workflow step 1.** Model the SKU catalog with versioned updates.
3. **Workflow step 2.** Record every catalog change as an event in the same transaction.
4. **Workflow step 3.** Reject stale concurrent updates.
5. **Workflow step 4.** Deploy and verify history and conflict handling.
6. **Deploy.** Run the synchronous deploy once and read the result. Re-running with no change is a no-op.  
   ```
   ample deploy . --name <app-name> --public --start "python3 run.py" --env S3_ENDPOINT=... --env S3_REGION=... --env S3_BUCKET=... --env S3_ACCESS_KEY_ID=... --env S3_SECRET_ACCESS_KEY=...
   ```
7. **Verify.** Run the pattern self-test(s) from the example (/p/transactional-workflows) and your own acceptance checks for the restaurants workflow.
   ```
   ample logs <deployment_id> --kind build
   ```

## Limitations
- The technical basis (transactional workflows on Django) was verified with the pattern fixture; the restaurants schema and workflow are an original design for this blueprint and were not executed as a separate application.
- No health, financial, privacy or other compliance claim is made. Allergen information must be kept accurate by the operator; nothing here validates food-safety claims.
- Public content and synthetic examples only until actual data-handling requirements have been reviewed.
- Verified on the python-3.12 template at s-1vcpu-1gb; region, request-duration limits and other sizes are unknown or unverified.
- Managed PostgreSQL 16 only; extensions, connection limits and backup or restore procedures are not verified.
- PutObject and GetObject with path-style addressing are verified; other S3 operations and CDN cache rules are not.

## Cost Estimate
Estimated 10.00 USD per month (size prices from pricing.toml at build revision a1b8c38919e59cd035ebabaced73cf84ece24371).
- app server x1 `s-1vcpu-1gb`: 5.00 USD
- managed PostgreSQL database x1 `s-1vcpu-1gb`: 5.00 USD

Always-on monthly price of the tested sizes; apps and databases auto-pause when idle. Buckets are allocation-priced per quota and not included.

## Verification Evidence
- canary_run on 2026-09-20T03:31:44Z at revision `03b6402b1b3e19178985f08ea4033804521d85d4-dirty (CLI b75e104)`: Django pattern fixture deployed on Ample (pip install into .ample/python from requirements.txt, then waitress serving project.wsgi from run.py reading PORT on the python-3.12 template); the transactional workflows checks passed: an optimistic version check and an event row written in the same transaction, a stale update rejected, and a history query over the application-owned events (history=2 conflict=rejected). The blueprint's Restaurants schema and workflow below build on that verified basis and were not separately executed. (expires 2027-03-19T03:31:44Z)

## Execution Binding
MCP tool `ample_deploy` (registry `mcp:ample_deploy`), schema hash `876465fce906da0c` observed 2026-09-21T03:19:59.461917+00:00 at revision `49962bcade4f`, binding state `current`, required scopes: servers:write, databases:read, buckets:read.