Enforce Private-File Authorization for Fastify

Summary

Private file access for a Fastify app on Ample. Verified on Fastify: 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.

Prerequisites

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

Infrastructure Requirements

• Compute
  Status: verified
  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
  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
  Buckets are S3-compatible with issued credentials; PutObject and GetObject are verified by canary. Other S3 operations are not verified.

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   Return 401 for unauthenticated requests and 403 for the wrong role; keep the bucket unpublished and stream objects through the app.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

Examples

• Fastify pattern fixture
  Verified private file access on Fastify.

Success Checks

• The app responds on its public URL
• Private-document-library check from the example
  Expect: see the pattern fixture checks

Limitations

• Verified on the node-22 template at s-1vcpu-1gb; other sizes and Fastify major versions are not verified.
• Region, compliance attestations and request-duration limits are unknown and not claimed.
• Managed PostgreSQL 16 only; extensions, connection limits and backup or restore procedures are not verified.
• PutObject and GetObject with path-style addressing are verified; other S3 operations are not.

Cost Estimate

• Monthly Amount: $10.00 (USD)
  Components:
  • App server: s-1vcpu-1gb (1 unit = $5.00)
  • Managed PostgreSQL database: s-1vcpu-1gb (1 unit = $5.00)
    Note: Always-on monthly price of the tested sizes; apps auto-pause when idle. Buckets are allocation-priced per quota and not included.

Evidence Summary

• Canary run: Fastify pattern fixture deployed on Ample; for this guide: a role-to-document access model with negative tests (401, 403) and an authorized private-bucket round-trip (private=ok).

Last Verified At

2026-09-21T01:14:18Z