### Host Vendor Portal with Flask: Private Documents

Deploy a vendor portal built with Flask on Ample using the private document library 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. A private S3-compatible bucket holds objects with credentials delivered as encrypted environment variables. Verified on Flask: a role-to-document access model with negative tests (401 without identity, 403 for the wrong role) and a private-bucket round-trip for the allowed role (private=ok). The vendor portal-specific behavior is your application code.

#### Representative Queries
- Host vendor portal with Flask: private documents
- Where can I host Vendor portal built with Flask?
- I need a role-to-document access model and negative authorization tests.

#### Resource Requirements
- Compute
- Postgres
- S3-compatible object storage

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

#### Framework
- Flask

#### Workload
- Vendor portal

#### Release Status
- Published

#### Support Status
- Verified

#### Execution Status
- Ready

#### Prerequisites
- A Flask project that builds and starts with the documented commands (pip install into .ample/python from requirements.txt, then waitress from app.py reading PORT on the python-3.12 template).
- A PostgreSQL driver reading DATABASE_URL at runtime (auto-provisioned when omitted, or supplied with --env).
- A bucket from `ample bucket create` with its credentials passed as encrypted S3_* environment variables.
- An Ample account token with servers:write, databases:read, buckets:read.

#### Workflow Steps
1. **Build and Start:** pip install into .ample/python from requirements.txt, then waitress from app.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 private document library: a role-to-document access model with negative tests (401 without identity, 403 for the wrong role) and a private-bucket round-trip for the allowed role (private=ok). Copy the approach into your schema; keep migrations idempotent and run them with --release-command.
3. **Wire Object Storage:** Create the bucket(s), then pass endpoint, region, bucket and keys as --env values. Use path-style addressing. Keep private data in an unpublished bucket.
4. **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.
5. **Verify:** Fetch the live URL and the pattern self-test route(s) (/p/private-document-library) from the example; then run your own checks. On failure read `ample logs  --kind build` then `--kind runtime`.

#### Success Checks
- App responds on its public URL (http_get on path: /, expect: ample canary flask patterns).
- Private-document-library self-test (http_get on path: /p/private-document-library, expect: private=ok with ?role=owner; 401 without, 403 for viewer).

#### Limitations
- Verified on the python-3.12 template at s-1vcpu-1gb with the example fixture; other sizes, templates and Flask major versions are not verified.
- The vendor portal itself (your identity integration and role assignments) 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.

#### Cost Estimate
- **Currency:** USD  
- **Monthly Amount:** 10.0  
- **Components:**  
   - App server (s-1vcpu-1gb): $5.0  
   - Managed PostgreSQL database (s-1vcpu-1gb): $5.0  
- **Note:** Always-on monthly price of the tested sizes; apps and databases auto-pause when idle. Buckets are allocation-priced per quota and not included.

#### Example
- **Flask Pattern Fixture:** Multi-pattern Flask app whose private document library module was checked live; the module is under tests/deploy-canaries/_pattern-modules (`tests/deploy-canaries/flask-patterns`).