# Host product catalog with Rails: relational catalog data

Deploy a product catalog built with Rails on Ample using the transactional workflows 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. Verified on Rails: an optimistic version check and an event row written in the same transaction, a stale update rejected, and a history query over the application-owned events (history=2 conflict=rejected). Not separately tested: your domain records, validation rules and concurrency policy; treat the product catalog-specific behavior as your application code.

## Representative Queries
- Host product catalog with Rails: relational catalog data
- Where can I host Product catalog built with Rails?
- I need catalog tables, transactional update logic and application-level access boundaries.

## Resource Requirements
- primitive:compute
- primitive:postgres

## Infrastructure Requirements
1. **Compute**  
   Apps run in isolated x86_64 Firecracker microVMs that auto-pause when idle and wake on request; sizes are the priced VM sizes.
2. **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.

## Framework
Rails  
## Workload
Product catalog  
## Release Status
published  
## Support Status
verified  
## Execution Status
ready  
## 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)
- An Ample account token with servers:write, databases: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 transactional workflows: an optimistic version check and an event row written in the same transaction, a stale update rejected, and a history query over the application-owned events (history=2 conflict=rejected). Copy the approach into your schema; keep migrations idempotent and run them with --release-command.
3. **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.
   ```
   ample deploy . --name  --public
   ```
4. **Verify**  
   Fetch the live URL and the pattern self-test route(s) (/p/transactional-workflows) from the example; then run your own checks. On failure read `ample logs  --kind build` then `--kind runtime`.
   ```
   ample logs  --kind build
   ```

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

## Success Checks
1. **App responds on its public URL**  
   - Kind: http_get  
   - Path: /  
   - Expect: ample canary rails patterns  
2. **Transactional-workflows self-test**  
   - Kind: http_get  
   - Path: /p/transactional-workflows  
   - Expect: tx=ok history=2 conflict=rejected

## 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 product catalog itself (your domain records, validation rules and concurrency policy) 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.
- Apps auto-pause when idle and wake on the next request; always-on is an operator setting, not a plan feature.
- Managed PostgreSQL 16 only; extensions, connection limits and backup or restore procedures are not verified; apps and their databases are placed together.

## Cost Estimate
- Currency: USD  
- Monthly Amount: 10.0  
- Authoritative: true  
- 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  
     - Monthly Amount: 5.0  
  - **managed PostgreSQL database**  
     - Size: s-1vcpu-1gb  
     - Quantity: 1.0  
     - Monthly Amount: 5.0  
- 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.

## Last Verified At
2026-09-20T21:55:28Z  
## Unknowns
- region availability is unknown until a verified region fact is recorded  
- compliance attestations are unknown; none are claimed

## Formats
- [HTML](/content/recipes/product-catalog/rails/relational-catalog/index.html)  
- [Markdown](/content/recipes/product-catalog/rails/relational-catalog.md)  
- [JSON](https://api.ample.computer/v1/catalog/recipes/page%3Arecipes%3Aproduct-catalog%3Arails%3Arelational-catalog)

## Next Actions
1. **Browse the catalog index**  
   - Method: GET  
   - Relative Path: /v1/catalog
2. **Search published recipes by intent, stack and constraints**  
   - Method: POST  
   - Relative Path: /v1/catalog/search  
3. **Prepare a side-effect-free deployment plan for an authorized project**  
   - Method: POST  
   - Relative Path: /v1/catalog/plan  
4. **Read the existing agent authentication setup**  
   - Method: GET  
   - Relative Path: /mcp/setup  
5. **Browse Product catalog**  
   - Method: GET  
   - Relative Path: /v1/catalog/nodes/workload%3Aproduct-catalog  
6. **Browse Rails**  
   - Method: GET  
   - Relative Path: /v1/catalog/nodes/stack%3Aframework-rails  
7. **Browse Transactional workflows**  
   - Method: GET  
   - Relative Path: /v1/catalog/nodes/pattern%3Atransactional-workflows  
8. **Browse Deploy web app**  
   - Method: GET  
   - Relative Path: /v1/catalog/nodes/intent%3Adeploy-web-app