## Host order tracking with Next.js: authorized file delivery

### Summary
Deploy a order tracking built with Next.js on Ample using the generated downloads 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, a private S3-compatible bucket holds objects with credentials delivered as encrypted environment variables. Verified on Next.js: an export query rendered to a CSV artifact stored with metadata in a private bucket and returned only to an authorized caller (401 without token, export=ok rows=3). Not separately tested: your export formats, retention policy and entitlement model; treat the order tracking-specific behavior as your application code.

### Representative Queries
- Host order tracking with Next.js: authorized file delivery
- Where can I host Order tracking built with Next.js?
- I need a file entitlement model and an application-enforced download authorization flow.

### Prerequisites
- A Next.js project that builds and starts with the documented commands (next build then next start -H 0.0.0.0 -p $PORT on the node-22 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**  
   next build then next start -H 0.0.0.0 -p $PORT on the node-22 template. The server must bind 0.0.0.0 on PORT.

2. **Implement the pattern on PostgreSQL**  
   The fixture's module implements generated downloads: an export query rendered to a CSV artifact stored with metadata in a private bucket and returned only to an authorized caller (401 without token, export=ok rows=3). 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 Keep private data in an unpublished bucket.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.  
   Command: ample deploy . --name  --public --env S3_ENDPOINT=... --env S3_REGION=... --env S3_BUCKET=... --env S3_ACCESS_KEY_ID=... --env S3_SECRET_ACCESS_KEY=...

5. **Verify**  
   Fetch the live URL and the pattern self-test route(s) (/p/generated-downloads) from the example; then run your own checks. On failure read `ample logs  --kind build` then `--kind runtime`.  
   Command: ample logs  --kind build

### Success Checks
- app responds on its public URL
- generated-downloads self-test

### Limitations
- Verified on the node-22 template at s-1vcpu-1gb with the example fixture; other sizes, templates and Next.js major versions are not verified.
- The order tracking itself (your export formats, retention policy and entitlement model) is application code and was not separately tested; the pattern checks are what was verified.

### Examples
- **Next.js pattern fixture**  
  Multi-pattern Next.js app whose generated downloads module was checked live; the module is under tests/deploy-canaries/_pattern-modules.

### Cost Estimate
- **Amount**: $10.00/month (USD)  
- **Breakdown**:
  - app server: s-1vcpu-1gb - $5.00
  - managed PostgreSQL database: s-1vcpu-1gb - $5.00
- *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.