# Host campaign site with Flask: Postgres-backed content

## Summary
Deploy a campaign site built with Flask on Ample using the relational records pattern. Compute runs the app in an isolated microVM behind a public HTTPS URL, a managed PostgreSQL 16 database is auto-provisioned and injected as DATABASE_URL, and a published bucket serves public assets from the CDN host. Verified on Flask: 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 campaign site-specific behavior as your application code.

## Resource Requirements
- **Compute**
- **Postgres**
- **CDN**

## 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. **CDN**  
   The CDN host serves objects from published buckets. It does not front app compute and is not a cache or key-value store.

## 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 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. **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. Publish only the bucket that serves public assets and reference its CDN URL.

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.
   
   ``` 
   ample deploy . --name  --public --start "python3 app.py" --env S3_ENDPOINT=... --env S3_REGION=... --env S3_BUCKET=... --env S3_ACCESS_KEY_ID=... --env S3_SECRET_ACCESS_KEY=... --env CDN_PUBLIC_URL=... 
   ```

5. **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 
   ```

## Examples
### Flask pattern fixture
- Multi-pattern Flask app whose relational records module was checked live; the module is under tests/deploy-canaries/_pattern-modules.
   
## Success Checks
- App responds on its public URL.  
   - **Path**: /  
   - **Expect**: ample canary flask patterns.

- Relational-records self-test  
   - **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 Flask major versions are not verified.
- The campaign site itself (your record schema, states and access rules) is application code and was not separately tested; the pattern checks are what was verified.
- Managed PostgreSQL 16 only; extensions, connection limits and backup or restore procedures are not verified; apps and their databases are placed together.

## Cost Estimate
- **Monthly Amount**: $10.00 (USD)
- **Components**:  
   - **App Server**: 1 x s-1vcpu-1gb - $5.00  
   - **Managed PostgreSQL Database**: 1 x s-1vcpu-1gb - $5.00  
- **Note**: Always-on monthly price of the tested sizes; buckets are allocation-priced per quota and not included.

## Evidence Summary
- **Canary Run**  
   - **Summary**: Flask pattern fixture deployed on Ample (pip install into .ample/python from requirements.txt, then waitress from app.py reading PORT on the python-3.12 template); checks passed for relational-records and configuration-secrets.
   - **Observed At**: 2026-09-21T01:14:18Z  
   - **Implementation Revision**: 50dbac567d2c5cc8e55e6c748a646be0025d9cfb-dirty (CLI 0.1.21)

## Last Verified
- **At**: 2026-09-21T01:14:18Z