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Authorize before touching storage: Return 401 for unauthenticated requests and 403 for the wrong role; keep the bucket unpublished and stream objects through the app.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