# Host subscription content with Rails: authorized file delivery

## Summary
Deploy a subscription content built with Rails 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 Rails: 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 subscription content-specific behavior as your application code.

## Representative Queries
- Host subscription content with Rails: authorized file delivery  
- Where can I host Subscription content built with Rails?  
- I need a file entitlement model and an application-enforced download authorization flow.

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

## Infrastructure Requirements
- **Compute**: Apps run in isolated x86_64 Firecracker microVMs that auto-pause when idle and wake on request; sizes are the priced VM sizes.
- **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.
- **S3-compatible object storage**: Buckets are S3-compatible with issued credentials; PutObject and GetObject are verified by canary. Other S3 operations are not verified.

## Framework
Rails

## Workload
Subscription content

## Prerequisites
- A Rails project that builds and starts with the documented commands (bundle install into vendor/bundle from Gemfile.lock (development and test groups skipped), then Puma via `rails server` reading PORT on the ruby-3.4 template with RAILS_ENV=production)  
- 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**: bundle install into vendor/bundle from Gemfile.lock (development and test groups skipped), then Puma via `rails server` reading PORT on the ruby-3.4 template with RAILS_ENV=production. 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`

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

## Success Checks
- App responds on its public URL (expect: ample canary rails patterns)
- Generated-downloads self-test (expect: export=ok rows=3 with token; 401 without)

## Limitations
- Verified on the ruby-3.4 template at s-1vcpu-1gb with the example fixture; other sizes, templates and Rails major versions are not verified.  
- The subscription content itself (your export formats, retention policy and entitlement model) is application code and was not separately tested; the pattern checks are what was verified.  
- Region, compliance attestations and request-duration limits are unknown and not claimed.

## Cost Estimate
- **Currency**: USD
- **Monthly Amount**: 10.0  
- **Basis**: Size prices from pricing.toml (loaded by the API) at build revision 1ac5595375130d45290090e82ed0f554ccd45405-dirty

- **Components**:  
   - app server (size: s-1vcpu-1gb, quantity: 1.0, monthlyAmount: 5.0)  
   - managed PostgreSQL database (size: s-1vcpu-1gb, quantity: 1.0, monthlyAmount: 5.0)

## Next Actions
- **[Browse the catalog index](https://api.ample.computer/v1/catalog)**
- **[Search published recipes by intent, stack and constraints](https://api.ample.com/computer/v1/catalog/search)**
- **[Prepare a side-effect-free deployment plan for an authorized project](https://api.ample.com/v1/catalog/plan)**
- **[Read the existing agent authentication setup](https://api.ample.com/mcp/setup)**
- **[Browse Subscription content](https://api.ample.com/v1/catalog/nodes/workload%3Asubscription-content)**