---

name: plutonium-resource description: Overview of Plutonium resources - what they are and how the pieces fit together

Plutonium Resources

A resource in Plutonium is the combination of four layers that work together to provide full CRUD functionality with minimal code.

The Four Layers

Copy┌─────────────────────────────────────────────────────────────────┐
│                           Resource                               │
├─────────────────────────────────────────────────────────────────┤
│  Model          │  Definition      │  Policy        │ Controller │
│  (WHAT it is)   │  (HOW it looks)  │  (WHO can act) │ (HOW it    │
│                 │                  │                │  responds)  │
├─────────────────────────────────────────────────────────────────┤
│  - attributes   │  - field types   │  - permissions │ - CRUD     │
│  - associations │  - inputs/forms  │  - scoping     │ - redirects│
│  - validations  │  - displays      │  - attributes  │ - params   │
│  - scopes       │  - actions       │                │            │
│  - callbacks    │  - filters       │                │            │
└─────────────────────────────────────────────────────────────────┘

Creating Resources

New Resources (from scratch)

Use the scaffold generator to create all four layers at once:

Copyrails g pu:res:scaffold Post title:string content:text:required published:boolean

This generates:

• app/models/post.rb - Model with validations
• app/definitions/post_definition.rb - Definition (empty, uses auto-detection)
• app/policies/post_policy.rb - Policy with sensible defaults
• app/controllers/posts_controller.rb - Controller (empty, inherits CRUD)
• Migration file

See plutonium-create-resource skill for full generator options.

From Existing Models

For existing Rails projects, you can convert models to Plutonium resources:

1. Include the module in your model:

Copyclass Post < ApplicationRecord
  include Plutonium::Resource::Record
  # Your existing code...
end

Or inherit from a base class that includes it:

Copyclass Post < ResourceRecord
  # Your existing code...
end

1. Generate the supporting files (definition, policy, controller):

Copyrails g pu:res:scaffold Post --no-migration

This creates definition, policy, and controller without touching your existing model.

1. Connect to a portal:

Copyrails g pu:res:conn Post --dest=admin_portal

Connecting to Portals

Resources must be connected to a portal to be accessible:

Copyrails g pu:res:conn Post --dest=admin_portal

This:

• Registers the resource in portal routes
• Creates portal-specific controller
• Creates portal-specific policy with attribute permissions

See plutonium-connect-resource skill for details.

Layer Responsibilities

Model (Data Layer)

Copyclass Post < ResourceRecord
  belongs_to :author, class_name: "User"
  has_many :comments

  validates :title, presence: true

  scope :published, -> { where(published: true) }
end

The model handles:

• Database schema and associations
• Data validation
• Business logic scopes
• Callbacks

Skills: plutonium-model, plutonium-model-features

Definition (UI Layer)

Copyclass PostDefinition < ResourceDefinition
  # Override auto-detected field types
  input :content, as: :markdown

  # Add filters and scopes
  filter :published, with: Plutonium::Query::Filters::Boolean
  scope :published

  # Add actions
  action :publish, interaction: PublishPostInteraction
end

The definition handles:

• Field type overrides (auto-detection handles most cases)
• Form input customization
• Display formatting
• Search, filters, scopes, sorting
• Actions (interactive operations)

Skills: plutonium-definition, plutonium-definition-fields, plutonium-definition-actions, plutonium-definition-query

Policy (Authorization Layer)

Copyclass PostPolicy < ResourcePolicy
  # Who can perform actions
  def create?
    user.present?
  end

  def read?
    true
  end

  def publish?
    user.admin? || record.author == user
  end

  # What records are visible
  relation_scope do |relation|
    return relation if user.admin?
    relation.where(author: user)
  end

  # What attributes are readable/writable
  def permitted_attributes_for_read
    %i[title content published author created_at]
  end

  def permitted_attributes_for_create
    %i[title content]
  end
end

The policy handles:

• Action authorization (create?, update?, destroy?, custom actions)
• Resource scoping (what records user can see)
• Attribute permissions (read/write access per field)

Skill: plutonium-policy

Controller (Request Layer)

Copyclass PostsController < ::ResourceController
  # Empty - all CRUD actions inherited automatically
end

Controllers are usually empty because they inherit full CRUD functionality. Customize only when needed:

Copyclass PostsController < ::ResourceController
  private

  def preferred_action_after_submit
    "index"  # Redirect to list instead of show
  end
end

The controller handles:

• Request/response cycle
• Redirect logic
• Custom parameter processing
• Non-standard authorization flows

Skill: plutonium-controller

Auto-Detection

Plutonium automatically detects from your model:

• All database columns with appropriate field types
• Associations (belongs_to, has_one, has_many)
• Attachments (Active Storage)
• Enums

You only need to declare when overriding defaults.

Portal-Specific Customization

Each portal can have its own definition that overrides the base:

Copy# Base definition
class PostDefinition < ResourceDefinition
  scope :published
end

# Admin portal sees more
class AdminPortal::PostDefinition < ::PostDefinition
  scope :draft
  scope :pending_review
  action :feature, interaction: FeaturePostInteraction
end

# Public portal is restricted
class PublicPortal::PostDefinition < ::PostDefinition
  # Only published scope, no actions
end

Workflow Summary

1. Generate - rails g pu:res:scaffold Model attributes... --dest=main_app
2. Connect - rails g pu:res:conn Model --dest=portal_name
3. Customize - Edit definition/policy as needed (model rarely needs changes)
4. Override per portal - Create portal-specific definitions when needed

Related Skills

• plutonium-model - Model structure and organization
• plutonium-model-features - has_cents, associations, scopes, routes
• plutonium-definition - Definition overview and structure
• plutonium-definition-fields - Fields, inputs, displays, columns
• plutonium-definition-actions - Actions and interactions
• plutonium-interaction - Writing interaction classes
• plutonium-definition-query - Search, filters, scopes, sorting
• plutonium-policy - Authorization and permissions
• plutonium-controller - Controller customization
• plutonium-views - Custom pages, displays, tables using Phlex
• plutonium-forms - Custom form templates and field builders
• plutonium-assets - TailwindCSS and component theming
• plutonium-package - Feature and portal packages
• plutonium-portal - Portal configuration and entity scoping
• plutonium-nested-resources - Parent/child routes and scoping
• plutonium-installation - Setting up Plutonium
• plutonium-rodauth - Authentication setup
• plutonium-create-resource - Scaffold generator details
• plutonium-connect-resource - Portal connection details