## Host approval workflow with FastAPI: relational workspace data

### Summary
Deploy an approval workflow built with FastAPI on Ample using the relational records pattern. Compute runs the app in an isolated microVM behind a public HTTPS URL, and a managed PostgreSQL 16 database is auto-provisioned and injected as DATABASE_URL.
- Verified on FastAPI: a workspace-scoped table, an explicit state machine (draft to review to published) that rejects invalid transitions, and a cross-workspace read that returns nothing (transitions=true isolation=true).
- Not separately tested: your record schema, states and access rules; treat the approval workflow-specific behavior as your application code.

### Representative Queries
- Host approval workflow with FastAPI: relational workspace data
- Where can I host Approval workflow built with FastAPI?
- I need a workspace-specific schema, state transitions and access rules.

### Workflow Steps
1. **Build and start**  
pip install into .ample/python from requirements.txt, then uvicorn from run.py reading PORT on the python-3.12 template. The server must bind 0.0.0.0 on PORT.
2. **Implement the pattern on PostgreSQL**  
The fixture's module implements relational records: a workspace-scoped table, an explicit state machine (draft to review to published) that rejects invalid transitions, and a cross-workspace read that returns nothing (transitions=true isolation=true). Copy the approach into your schema; keep migrations idempotent and run them with --release-command.
3. **Deploy**  
Run the synchronous deploy once and read the result (exit 0 live, 1 failed, 2 blocked). Re-running with no change is a no-op.  
`ample deploy . --name  --public --start "python3 run.py"`
4. **Verify**  
Fetch the live URL and the pattern self-test route(s) (/p/relational-records) from the example; then run your own checks. On failure read `ample logs  --kind build` then `--kind runtime`.  
`ample logs  --kind build`

### Prerequisites
- A FastAPI project that builds and starts with the documented commands.
- A PostgreSQL driver reading DATABASE_URL at runtime (auto-provisioned when omitted, or supplied with --env).
- An Ample account token with servers:write, databases:read.

### Success Checks
- app responds on its public URL
- relational-records self-test
  - Kind: http_get
  - Path: /p/relational-records
  - Expect: records=ok transitions=true isolation=true

### Limitations
- Verified on the python-3.12 template at s-1vcpu-1gb with the example fixture; other sizes, templates and FastAPI major versions are not verified.
- The approval workflow itself is application code and was not separately tested; the pattern checks are what was verified.
- Region, compliance attestations and request-duration limits are unknown and not claimed.
- Apps auto-pause when idle and wake on the next request; always-on is an operator setting, not a plan feature.
- Managed PostgreSQL 16 only; extensions, connection limits and backup or restore procedures are not verified.

### Cost Estimate
- Monthly Amount: $10.00
- Currency: USD
- Components:
  - App server: s-1vcpu-1gb
  - Managed PostgreSQL database: s-1vcpu-1gb