Allow app to opt out of precompiling activestorage js assets (#43967)

actioncable/lib/action_cable/engine.rb

@@ -25,8 +25,8 @@ class Engine < Rails::Engine # :nodoc:
 
     initializer "action_cable.asset" do
       config.after_initialize do |app|
-        if Rails.application.config.respond_to?(:assets) && app.config.action_cable.precompile_assets
-          Rails.application.config.assets.precompile += %w( actioncable.js actioncable.esm.js )
+        if app.config.respond_to?(:assets) && app.config.action_cable.precompile_assets
+          app.config.assets.precompile += %w( actioncable.js actioncable.esm.js )
         end
       end
     end

activestorage/lib/active_storage/engine.rb

@@ -30,6 +30,7 @@ class Engine < Rails::Engine # :nodoc:
     config.active_storage.analyzers = [ ActiveStorage::Analyzer::ImageAnalyzer::Vips, ActiveStorage::Analyzer::ImageAnalyzer::ImageMagick, ActiveStorage::Analyzer::VideoAnalyzer, ActiveStorage::Analyzer::AudioAnalyzer ]
     config.active_storage.paths = ActiveSupport::OrderedOptions.new
     config.active_storage.queues = ActiveSupport::InheritableOptions.new
+    config.active_storage.precompile_assets = true
 
     config.active_storage.variable_content_types = %w(
       image/png
@@ -167,8 +168,10 @@ class Engine < Rails::Engine # :nodoc:
     end
 
     initializer "active_storage.asset" do
-      if Rails.application.config.respond_to?(:assets)
-        Rails.application.config.assets.precompile += %w( activestorage activestorage.esm )
+      config.after_initialize do |app|
+        if app.config.respond_to?(:assets) && app.config.active_storage.precompile_assets
+          app.config.assets.precompile += %w( activestorage activestorage.esm )
+        end
       end
     end
 

guides/source/configuring.md

@@ -1972,6 +1972,11 @@ Cable as part of your normal Rails server.
 You can find more detailed configuration options in the
 [Action Cable Overview](action_cable_overview.html#configuration).
 
+#### `config.action_cable.precompile_assets`
+
+Determines whether the Action Cable assets should be added to the asset pipeline precompilation. It
+has no effect if Sprockets is not used. The default value is `true`.
+
 ### Configuring Active Storage
 
 `config.active_storage` provides the following configuration options:
@@ -2192,6 +2197,11 @@ The default value depends on the `config.load_defaults` target version:
 | (original)            | `false`              |
 | 7.0                   | `true`               |
 
+#### `config.active_storage.precompile_assets`
+
+Determines whether the Active Storage assets should be added to the asset pipeline precompilation. It
+has no effect if Sprockets is not used. The default value is `true`.
+
 ### Configuring Action Text
 
 #### `config.action_text.attachment_tag_name`