# Enforce private-file authorization for Express

## Summary
Private file access for an Express app on Ample. Verified on Express: a role-to-document access model with negative tests (401, 403) and an authorized private-bucket round-trip (private=ok). Build and start: `npm install`, `npm run build --if-present`, `npm run start` on the node-22 template.

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

## Infrastructure Requirements
### Compute
- **Status**: verified  
- **Summary**: Apps run in isolated x86_64 Firecracker microVMs that auto-pause when idle and wake on request; sizes are the priced VM sizes.

### Postgres
- **Status**: verified  
- **Summary**: 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
- **Status**: verified  
- **Summary**: Buckets are S3-compatible with issued credentials; PutObject and GetObject are verified by canary. Other S3 operations are not verified.

## Workload
Enforce private-file authorization

## Prerequisites
1. A Express project (npm install, npm run build --if-present, npm run start on the node-22 template)
2. A PostgreSQL driver reading DATABASE_URL at runtime
3. A bucket from `ample bucket create` with credentials passed as encrypted S3_* environment variables
4. An Ample account token with servers:write, databases:read, buckets:read.

## Workflow Steps
1. **Build and start**: `npm install`, `npm run build --if-present`, `npm run start` on the node-22 template; the server must bind 0.0.0.0 on PORT.
2. **Create the bucket and pass its credentials**: Create it once with `ample bucket create`, then pass endpoint, region, bucket and keys with --env; use path-style addressing.
   - Command: `ample deploy . --name  --public --env S3_ENDPOINT=... --env S3_REGION=... --env S3_BUCKET=... --env S3_ACCESS_KEY_ID=... --env S3_SECRET_ACCESS_KEY=...`
3. **Authorize before touching storage**: Return 401 for unauthenticated requests and 403 for the wrong role; keep the bucket unpublished and stream objects through the app.
4. **Verify**: Fetch the live URL and /p/private-document-library on the example; on failure read the build and runtime logs.
   - Command: `ample logs  --kind build`

## Success Checks
- **HTTP GET** on public URL should respond  
- **HTTP GET** on `/p/private-document-library` should show the pattern fixture checks.

## Limitations
- Verified on the node-22 template at s-1vcpu-1gb; other sizes and Express major versions are not verified.
- Region and compliance attestations are unknown and not claimed.

## Cost Estimate
- **Currency**: USD  
- **Monthly Amount**: 10.0

### Components
- **App server** (s-1vcpu-1gb): $5.00/month  
- **Managed PostgreSQL database** (s-1vcpu-1gb): $5.00/month

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

## Next Actions
1. **Browse the catalog index**  
2. **Search published recipes by intent, stack and constraints**  
3. **Prepare a side-effect-free deployment plan for an authorized project**  
4. **Read the existing agent authentication setup**  
5. **Browse Express**  
6. **Browse Connect app to storage**  
7. **Browse Private document library**