# Host inventory manager with Rails: relational workspace data

Deploy a inventory manager built with Rails on Ample using the relational records 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: a workspace-scoped table, an explicit state machine (draft to review to published) that rejects invalid transitions, and a cross-workspace read that returns nothing (transitions=true isolation=true). Not separately tested: your record schema, states and access rules; treat the inventory manager-specific behavior as your application code.

## Representative Queries
- Host inventory manager with Rails: relational workspace data
- Where can I host Inventory manager built with Rails?
- I need a workspace-specific schema, state transitions and access rules.

## Resource Requirements
- Compute
- Postgres

## 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.

## Framework
Rails

## Workload
Inventory manager

## 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

## Tested Configuration
- **Template:** ruby-3.4
- **Runtime:** ruby
- **Size:** s-1vcpu-1gb
- **Install:** bundle config set --local path vendor/bundle && bundle config set --local without 'development test' && bundle install
- **Start:** bundle exec rails server -b 0.0.0.0 -p $PORT

## Input Schema
```json
{
  "additionalProperties": false,
  "properties": {
    "env": {
      "description": "Encrypted environment variables (bucket credentials, secrets)",
      "items": {
        "pattern": "^[A-Z][A-Z0-9_]*=.*$",
        "type": "string"
      },
      "maxItems": 50,
      "type": "array"
    },
    "name": {
      "description": "App name",
      "maxLength": 63,
      "minLength": 1,
      "pattern": "^[a-z0-9-]+$",
      "type": "string"
    },
    "path": {
      "description": "Project directory or ample.toml service",
      "maxLength": 512,
      "minLength": 1,
      "type": "string"
    },
    "release_command": {
      "description": "Migration command run before activation",
      "maxLength": 512,
      "type": "string"
    }
  },
  "required": ["name", "path"],
  "type": "object"
}
```

## 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 relational records: a workspace-scoped table, an explicit state machine (draft to review to published) that rejects invalid transitions, and a cross-workspace read that returns nothing (transitions=true isolation=true). 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.  
   ```bash  
   ample deploy . --name --public  
   ```  
4. **Verify**  
   Fetch the live URL and the pattern self-test route(s) (/p/relational-records) from the example; then run your own checks. On failure read `ample logs --kind build` then `--kind runtime`.  
   ```bash  
   ample logs --kind build  
   ```

## Examples
- **Title:** Rails pattern fixture  
  **Description:** Multi-pattern Rails app whose relational records module was checked live; the module is under tests/deploy-canaries/_pattern-modules.  
  **Source Ref:** tests/deploy-canaries/rails-patterns

## Success Checks
- **Description:** app responds on its public URL  
   **Kind:** http_get  
   **Path:** /  
   **Expect:** ample canary rails patterns  
- **Description:** relational-records self-test  
   **Kind:** http_get  
   **Path:** /p/relational-records  
   **Expect:** records=ok transitions=true isolation=true

## 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 inventory manager itself (your record schema, states and access rules) 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  
- **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.
- **Components:**  
  - App server: size s-1vcpu-1gb, monthly amount 5.0  
  - Managed PostgreSQL database: size s-1vcpu-1gb, monthly amount 5.0

## Evidence Summary
1. **Kind:** canary_run  
   **Summary:** Rails pattern fixture deployed on Ample (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); checks passed for relational-records and configuration-secrets. Pattern proof: a workspace-scoped table, an explicit state machine (draft to review to published) that rejects invalid transitions, and a cross-workspace read that returns nothing (transitions=true isolation=true).  
   **Observed At:** 2026-09-20T21:55:28Z  
   **Implementation Revision:** 4f7cb9813c1f-dirty (CLI 4f7cb98)  
   **Expires At:** 2027-03-19T21:55:28Z  
   **Scope:** {"checks":["/p/relational-records"],"pattern":"pattern:relational-records","template":"ruby-3.4"}
2. **Kind:** canary_run  
   **Summary:** The same Rails app deployed with a --release-command migration; the marker it created was readable after activation.  
   **Observed At:** 2026-09-20T21:55:28Z  
   **Implementation Revision:** 4f7cb9813c1f-dirty (CLI 4f7cb98)  
   **Expires At:** 2027-03-19T21:55:28Z  
   **Scope:** {"pattern":"pattern:relational-records"}

## Formats
- **HTML:** [View here](/content/recipes/inventory-manager/rails/relational-workspace/index.html)  
- **Markdown:** [View here](/content/recipes/inventory-manager/rails/relational-workspace.md)  
- **JSON:** [View here](https://api.ample.computer/v1/catalog/recipes/page%3Arecipes%3Ainventory-manager%3Arails%3Arelational-workspace)

## Next Actions
- **Action ID:** browse-catalog  
  **Label:** Browse the catalog index  
- **Action ID:** search-recipes  
  **Label:** Search published recipes by intent, stack and constraints  
- **Action ID:** plan:page:recipes:inventory-manager:rails:relational-workspace  
  **Label:** Prepare a side-effect-free deployment plan for an authorized project  
- **Action ID:** auth-setup  
  **Label:** Read the existing agent authentication setup  
- **Action ID:** browse:workload:inventory-manager  
  **Label:** Browse Inventory manager  
- **Action ID:** browse:stack:framework-rails  
  **Label:** Browse Rails  
- **Action ID:** browse:pattern:relational-records  
  **Label:** Browse Relational records  
- **Action ID:** browse:intent:deploy-web-app  
  **Label:** Browse Deploy web app