Summary

Add --pro and --rsc flags to the existing rails g react_on_rails:install generator to enable native setup of React on Rails Pro and React Server Components.

New commands:

rails g react_on_rails:install --pro      # Sets up Pro with Node Renderer
rails g react_on_rails:install --rsc      # Sets up RSC (includes Pro)

Motivation

Currently, setting up React on Rails Pro or RSC requires manual file creation:

• Creating config/initializers/react_on_rails_pro.rb
• Creating client/node-renderer.js
• Adding processes to Procfile.dev
• Installing npm packages manually
• For RSC: webpack config, component wrappers, routes

This is error-prone and doesn't follow the pattern of the existing generator which handles all setup automatically.

Proposed Implementation

Phase 1: Foundation

• Add --pro and --rsc class options to InstallGenerator
• Add detection helpers (use_pro?, use_rsc?, pro_gem_installed?)
• Add prerequisite validation (Pro gem must be installed)

Phase 2: Pro Generator

When --pro is used:

• Create config/initializers/react_on_rails_pro.rb with Node Renderer config
• Create client/node-renderer.js bootstrap file
• Append node-renderer process to Procfile.dev
• Install react-on-rails-pro and react-on-rails-pro-node-renderer npm packages

Phase 3: RSC Generator

When --rsc is used (automatically includes Pro):

• Create RSC webpack config (rscWebpackConfig.js)
• Create RSC example components with proper wrapper pattern
• Add RSC bundle watcher to Procfile.dev
• Add rsc_payload_route to routes
• Install RSC npm packages

Phase 4: Testing

• Unit tests for prerequisite validation
• Integration tests for --pro flag
• Integration tests for --rsc flag
• Test combinations with existing flags (--typescript, --redux, --rspack)

Phase 5: Documentation

• Update generator USAGE file
• Update docs with Pro/RSC generator options

Design Decisions

Additive Pattern (Sidekiq-style)

Follow Sidekiq's open-core pattern - extend the existing generator with flags rather than creating separate generators. Single entry point is cleaner UX, and Pro adds capabilities, not separate workflows.

--rsc Implies --pro

RSC technically requires Pro (can't use RSC without it). This reduces redundant typing and follows Rails convention (e.g., --api implies many other changes).

Node Renderer is Core Pro

When --pro is used, Node Renderer is set up by default. Node Renderer is the primary reason to upgrade to Pro - ExecJS is described as crash-prone at scale in Pro docs.

No Separate Migration Generator

The --pro flag works for both fresh installs AND existing React on Rails apps. Adding Pro to an existing app is the normal flow (most users already have React on Rails), and Pro-specific files are inherently additive.

Additive File Operations

Pro/RSC file generation uses additive operations (append_to_file, inject_into_file) that work on both fresh and existing apps. This makes the generator idempotent and safe to run multiple times.

Compatibility

Both flags should work with existing flags:

• --typescript / --no-typescript
• --redux
• --rspack

Success Criteria

• rails g react_on_rails:install --pro creates working Pro setup
• rails g react_on_rails:install --rsc creates working RSC setup
• All existing tests continue to pass
• Generated app starts and renders correctly