rails-engine-integration.md

In your engine

• At the top of config/initializers/react_on_rails.rb

ActiveSupport.on_load(:action_view) do
  include ReactOnRailsHelper
end

• In your <engine_name>.gemspec:

s.add_dependency 'react_on_rails', '~> 6'

• In your lib/<engine_name>.rb (the entry point for your engine)

require "react_on_rails"

• In your lib/tasks/<engine_name>_tasks.rake:

Rake.application.remove_task('react_on_rails:assets:compile_environment')

task 'react_on_rails:assets:compile_environment' do
  path = File.join(YourEngineName::Engine.root, 'client')
  sh "cd #{path} && #{ReactOnRails.configuration.npm_build_production_command}"
end

In the project including your engine

Place gem 'react_on_rails', '~> 6' before the gem pointing at your engine in your gemfile.

This is necessary because React on Rails attaches itself to the rake assets:precompile task. It then uses a direct path to cd into client, which will not exist in the main app that includes your engine. Since you'll always be precompiling assets in the parent app, this will always fail. The workaround then, is to remove the task and replace it with one that goes into your Engine's root. The reason you have to include the react on rails gem before your engine is so that the react_on_rails:assets:compile_environment task is defined by the time your engine gets loaded to remove it.

Requiring react_on_rails and including the helper will get rid of any issues where react on rails or react_component is undefined.

As far as solving the assets issue, lib/tasks/assets.rake in react_on_rails would somehow have to know that react_on_rails was included in an engine, and decide the path accordingly. This might be impossible, especially in the case of multiple engines using react_on_rails in a single application. Another solution would be to detach this rake task from the rails assets:precompile task, and let people use it separately.