[WIP] Hydrate components immediately after downloading chunks

lib/react_on_rails/configuration.rb

@@ -9,6 +9,7 @@ def self.configure
   end
 
   DEFAULT_GENERATED_ASSETS_DIR = File.join(%w[public webpack], Rails.env).freeze
+  DEFAULT_RSC_RENDERING_URL = "rsc/".freeze
 
   def self.configuration
     @configuration ||= Configuration.new(
@@ -42,7 +43,9 @@ def self.configuration
       make_generated_server_bundle_the_entrypoint: false,
       defer_generated_component_packs: true,
       # forces the loading of React components
-      force_load: false
+      force_load: false,
+      auto_load_server_components: true,
+      rsc_rendering_url: DEFAULT_RSC_RENDERING_URL
     )
   end
 
@@ -57,7 +60,7 @@ class Configuration
                   :same_bundle_for_client_and_server, :rendering_props_extension,
                   :make_generated_server_bundle_the_entrypoint,
                   :defer_generated_component_packs, :rsc_bundle_js_file,
-                  :force_load
+                  :force_load, :auto_load_server_components, :rsc_rendering_url
 
     # rubocop:disable Metrics/AbcSize
     def initialize(node_modules_location: nil, server_bundle_js_file: nil, prerender: nil,
@@ -73,7 +76,7 @@ def initialize(node_modules_location: nil, server_bundle_js_file: nil, prerender
                    i18n_dir: nil, i18n_yml_dir: nil, i18n_output_format: nil,
                    random_dom_id: nil, server_render_method: nil, rendering_props_extension: nil,
                    components_subdirectory: nil, auto_load_bundle: nil, force_load: nil,
-                   rsc_bundle_js_file: nil)
+                   rsc_bundle_js_file: nil, auto_load_server_components: nil, rsc_rendering_url: nil)
       self.node_modules_location = node_modules_location.present? ? node_modules_location : Rails.root
       self.generated_assets_dirs = generated_assets_dirs
       self.generated_assets_dir = generated_assets_dir
@@ -113,6 +116,8 @@ def initialize(node_modules_location: nil, server_bundle_js_file: nil, prerender
       self.make_generated_server_bundle_the_entrypoint = make_generated_server_bundle_the_entrypoint
       self.defer_generated_component_packs = defer_generated_component_packs
       self.force_load = force_load
+      self.auto_load_server_components = auto_load_server_components
+      self.rsc_rendering_url = rsc_rendering_url
     end
     # rubocop:enable Metrics/AbcSize
 

lib/react_on_rails/helper.rb

@@ -124,6 +124,7 @@ def react_component(component_name, options = {})
     # @option options [Boolean] :raise_on_prerender_error Set to true to raise exceptions during server-side rendering
     # Any other options are passed to the content tag, including the id.
     def stream_react_component(component_name, options = {})
+      options = options.merge(force_load: true) unless options.key?(:force_load)
       run_stream_inside_fiber do
         internal_stream_react_component(component_name, options)
       end
@@ -193,17 +194,18 @@ def react_component_hash(component_name, options = {})
     # props: Ruby Hash or JSON string which contains the properties to pass to the redux store.
     # Options
     #    defer: false -- pass as true if you wish to render this below your component.
-    def redux_store(store_name, props: {}, defer: false)
+    #    force_load: false -- pass as true if you wish to hydrate this store immediately instead of
+    #                        waiting for the page to load.
+    def redux_store(store_name, props: {}, defer: false, force_load: false)
       redux_store_data = { store_name: store_name,
-                           props: props }
+                           props: props,
+                           force_load: force_load }
       if defer
-        @registered_stores_defer_render ||= []
-        @registered_stores_defer_render << redux_store_data
+        registered_stores_defer_render << redux_store_data
         "YOU SHOULD NOT SEE THIS ON YOUR VIEW -- Uses as a code block, like <% redux_store %> " \
           "and not <%= redux store %>"
       else
-        @registered_stores ||= []
-        @registered_stores << redux_store_data
+        registered_stores << redux_store_data
         result = render_redux_store_data(redux_store_data)
         prepend_render_rails_context(result)
       end
@@ -215,9 +217,9 @@ def redux_store(store_name, props: {}, defer: false)
     # client side rendering of this hydration data, which is a hidden div with a matching class
     # that contains a data props.
     def redux_store_hydration_data
-      return if @registered_stores_defer_render.blank?
+      return if registered_stores_defer_render.blank?
 
-      @registered_stores_defer_render.reduce(+"") do |accum, redux_store_data|
+      registered_stores_defer_render.reduce(+"") do |accum, redux_store_data|
         accum << render_redux_store_data(redux_store_data)
       end.html_safe
     end
@@ -400,6 +402,25 @@ def run_stream_inside_fiber
       rendering_fiber.resume
     end
 
+    def registered_stores
+      @registered_stores ||= []
+    end
+
+    def registered_stores_defer_render
+      @registered_stores_defer_render ||= []
+    end
+
+    def registered_stores_including_deferred
+      registered_stores + registered_stores_defer_render
+    end
+
+    def create_render_options(react_component_name, options)
+      # If no store dependencies are passed, default to all registered stores up till now
+      options[:store_dependencies] ||= registered_stores_including_deferred.map { |store| store[:store_name] }
+      ReactOnRails::ReactComponent::RenderOptions.new(react_component_name: react_component_name,
+                                                      options: options)
+    end
+
     def internal_stream_react_component(component_name, options = {})
       options = options.merge(stream?: true)
       result = internal_react_component(component_name, options)
@@ -510,7 +531,8 @@ def build_react_component_result_for_server_rendered_hash(
       )
     end
 
-    def compose_react_component_html_with_spec_and_console(component_specification_tag, rendered_output, console_script)
+    def compose_react_component_html_with_spec_and_console(component_specification_tag, rendered_output,
+                                                           console_script)
       # IMPORTANT: Ensure that we mark string as html_safe to avoid escaping.
       html_content = <<~HTML
         #{rendered_output}
@@ -546,18 +568,20 @@ def internal_react_component(react_component_name, options = {})
       # (re-hydrate the data). This enables react rendered on the client to see that the
       # server has already rendered the HTML.
 
-      render_options = ReactOnRails::ReactComponent::RenderOptions.new(react_component_name: react_component_name,
-                                                                       options: options)
+      render_options = create_render_options(react_component_name, options)
 
       # Setup the page_loaded_js, which is the same regardless of prerendering or not!
       # The reason is that React is smart about not doing extra work if the server rendering did its job.
       component_specification_tag = content_tag(:script,
                                                 json_safe_and_pretty(render_options.client_props).html_safe,
                                                 type: "application/json",
                                                 class: "js-react-on-rails-component",
+                                                id: "js-react-on-rails-component-#{render_options.dom_id}",
                                                 "data-component-name" => render_options.react_component_name,
                                                 "data-trace" => (render_options.trace ? true : nil),
-                                                "data-dom-id" => render_options.dom_id)
+                                                "data-dom-id" => render_options.dom_id,
+                                                "data-store-dependencies" => render_options.store_dependencies.to_json,
+                                                "data-force-load" => (render_options.force_load ? true : nil))
 
       if render_options.force_load
         component_specification_tag.concat(
@@ -579,12 +603,22 @@ def internal_react_component(react_component_name, options = {})
     end
 
     def render_redux_store_data(redux_store_data)
-      result = content_tag(:script,
-                           json_safe_and_pretty(redux_store_data[:props]).html_safe,
-                           type: "application/json",
-                           "data-js-react-on-rails-store" => redux_store_data[:store_name].html_safe)
+      store_hydration_data = content_tag(:script,
+                                         json_safe_and_pretty(redux_store_data[:props]).html_safe,
+                                         type: "application/json",
+                                         "data-js-react-on-rails-store" => redux_store_data[:store_name].html_safe,
+                                         "data-force-load" => (redux_store_data[:force_load] ? true : nil))
+
+      if redux_store_data[:force_load]
+        store_hydration_data.concat(
+          content_tag(:script, <<~JS.strip_heredoc.html_safe
+            ReactOnRails.reactOnRailsStoreLoaded('#{redux_store_data[:store_name]}');
+          JS
+          )
+        )
+      end
 
-      prepend_render_rails_context(result)
+      prepend_render_rails_context(store_hydration_data)
     end
 
     def props_string(props)
@@ -641,7 +675,7 @@ def server_rendered_react_component(render_options) # rubocop:disable Metrics/Cy
       js_code = ReactOnRails::ServerRenderingJsCode.server_rendering_component_js_code(
         props_string: props_string(props).gsub("\u2028", '\u2028').gsub("\u2029", '\u2029'),
         rails_context: rails_context(server_side: true).to_json,
-        redux_stores: initialize_redux_stores,
+        redux_stores: initialize_redux_stores(render_options),
         react_component_name: react_component_name,
         render_options: render_options
       )
@@ -675,17 +709,20 @@ def server_rendered_react_component(render_options) # rubocop:disable Metrics/Cy
       result
     end
 
-    def initialize_redux_stores
+    def initialize_redux_stores(render_options)
       result = +<<-JS
       ReactOnRails.clearHydratedStores();
       JS
 
-      return result unless @registered_stores.present? || @registered_stores_defer_render.present?
+      store_dependencies = render_options.store_dependencies
+      return result unless store_dependencies.present?
 
       declarations = +"var reduxProps, store, storeGenerator;\n"
-      all_stores = (@registered_stores || []) + (@registered_stores_defer_render || [])
+      store_objects = registered_stores_including_deferred.select do |store|
+        store_dependencies.include?(store[:store_name])
+      end
 
-      result << all_stores.each_with_object(declarations) do |redux_store_data, memo|
+      result << store_objects.each_with_object(declarations) do |redux_store_data, memo|
         store_name = redux_store_data[:store_name]
         props = props_string(redux_store_data[:props])
         memo << <<-JS.strip_heredoc

lib/react_on_rails/packs_generator.rb

@@ -44,13 +44,60 @@ def create_pack(file_path)
       puts(Rainbow("Generated Packs: #{output_path}").yellow)
     end
 
+    def first_js_statement_in_code(content)
+      return "" if content.nil? || content.empty?
+
+      start_index = 0
+      content_length = content.length
+
+      while start_index < content_length
+        # Skip whitespace
+        while start_index < content_length && content[start_index].match?(/\s/)
+          start_index += 1
+        end
+
+        break if start_index >= content_length
+
+        current_chars = content[start_index, 2]
+
+        case current_chars
+        when '//'
+          # Single-line comment
+          newline_index = content.index("\n", start_index)
+          return "" if newline_index.nil?
+          start_index = newline_index + 1
+        when '/*'
+          # Multi-line comment
+          comment_end = content.index('*/', start_index)
+          return "" if comment_end.nil?
+          start_index = comment_end + 2
+        else
+          # Found actual content
+          next_line_index = content.index("\n", start_index)
+          return next_line_index ? content[start_index...next_line_index].strip : content[start_index..].strip
+        end
+      end
+
+      ""
+    end
+
+    def is_client_entrypoint?(file_path)
+      content = File.read(file_path)
+      # has "use client" directive. It can be "use client" or 'use client'
+      first_js_statement_in_code(content).match?(/^["']use client["'](?:;|\s|$)/)
+    end
+
     def pack_file_contents(file_path)
       registered_component_name = component_name(file_path)
+      register_as_server_component = ReactOnRails.configuration.auto_load_server_components && !is_client_entrypoint?(file_path)
+      import_statement = register_as_server_component ? "" : "import #{registered_component_name} from '#{relative_component_path_from_generated_pack(file_path)}';"
+      register_call = register_as_server_component ? "registerServerComponent(\"#{registered_component_name}\")" : "register({#{registered_component_name}})";
+
       <<~FILE_CONTENT
         import ReactOnRails from 'react-on-rails';
-        import #{registered_component_name} from '#{relative_component_path_from_generated_pack(file_path)}';
+        #{import_statement}
 
-        ReactOnRails.register({#{registered_component_name}});
+        ReactOnRails.#{register_call};
       FILE_CONTENT
     end
 

lib/react_on_rails/react_component/render_options.rb

@@ -119,6 +119,10 @@ def rsc?
         options[:rsc?]
       end
 
+      def store_dependencies
+        options[:store_dependencies]
+      end
+
       private
 
       attr_reader :options

node_package/src/CallbackRegistry.ts

@@ -0,0 +1,50 @@
+import { ItemRegistrationCallback } from "./types";
+
+export default class CallbackRegistry<T> {
+  private registeredItems = new Map<string, T>();
+  private callbacks = new Map<string, Array<ItemRegistrationCallback<T>>>();
+
+  set(name: string, item: T): void {
+    this.registeredItems.set(name, item);
+
+    const callbacks = this.callbacks.get(name) || [];
+    callbacks.forEach(callback => {
+      setTimeout(() => callback(item), 0);
+    });
+    this.callbacks.delete(name);
+  }
+
+  get(name: string): T | undefined {
+    return this.registeredItems.get(name);
+  }
+
+  has(name: string): boolean {
+    return this.registeredItems.has(name);
+  }
+
+  clear(): void {
+    this.registeredItems.clear();
+  }
+
+  getAll(): Map<string, T> {
+    return this.registeredItems;
+  }
+
+  onItemRegistered(name: string, callback: ItemRegistrationCallback<T>): void {
+    const existingItem = this.registeredItems.get(name);
+    if (existingItem) {
+      setTimeout(() => callback(existingItem), 0);
+      return;
+    }
+
+    const callbacks = this.callbacks.get(name) || [];
+    callbacks.push(callback);
+    this.callbacks.set(name, callbacks);
+  }
+
+  getOrWaitForItem(name: string): Promise<T> {
+    return new Promise((resolve) => {
+      this.onItemRegistered(name, resolve);
+    });
+  }
+}