Rake task for generating stories from component previews

Author: Nicholas Barone

lib/rails/storybook.rb

@@ -0,0 +1,2 @@
+require_relative "../storybook.rb"
+# TODO: Fix the gem naming, etc

lib/storybook.rb

@@ -1,6 +1,5 @@
 require "storybook/version"
+require "storybook/preview"
+require "storybook/railtie" if defined?(Rails::Railtie)
 
-module Storybook
-  class Error < StandardError; end
-  # Your code goes here...
-end
+module Storybook; end

lib/storybook/preview.rb

@@ -0,0 +1,25 @@
+module Storybook
+  module Preview
+    def self.included(base)
+      base.extend ClassMethods
+    end
+
+    module ClassMethods
+      def to_csf
+        { title: component_name, stories: stories }
+      end
+
+      def stories
+        instance_methods(false).collect { |name| story(name) }
+      end
+
+      def story(name)
+        { name:, parameters: { server: { id: "#{component_name&.underscore}/#{name}" } } }
+      end
+
+      def component_name
+        $1 if name  =~ /(.+Component)(?=Preview)/
+      end
+    end
+  end
+end

lib/storybook/railtie.rb

@@ -0,0 +1,14 @@
+require "storybook"
+require "rails"
+
+# https://gist.github.com/ntamvl/7a6658b4cd82d6fbd15434f0a9953411
+module Storybook
+  class Railtie < Rails::Railtie
+    railtie_name :storybook
+
+    rake_tasks do
+      path = File.expand_path(__dir__)
+      Dir.glob("#{path}/tasks/**/*.rake").each { |f| load f }
+    end
+  end
+end

lib/storybook/tasks/stories.rake

@@ -0,0 +1,18 @@
+namespace :storybook do
+  desc "Write CSF JSON stories for all Stories"
+  task stories: :environment do
+    previews_dir = Rails.root.join("test/components/previews")
+    Dir.glob("#{previews_dir}/**/*_preview.rb").each { |file| require file }
+
+    stories = ViewComponent::Preview.descendants.map do |preview|
+      [ preview.component_name&.underscore, preview.to_csf ] if preview < Storybook::Preview
+    end
+
+    stories_dir = "stories"
+    stories.each do |path, story|
+      File.open(Rails.root.join("#{stories_dir}/#{path}.stories.json"), "w") do |f|
+        f.write(JSON.pretty_generate(story))
+      end
+    end
+  end
+end