Enable Subresource Integrity

lib/webpacker/sri_manifest_extensions.rb

@@ -0,0 +1,29 @@
+# frozen_string_literal: true
+
+module Webpacker::SriManifestExtensions
+  def lookup(name, pack_type = {})
+    asset = super
+
+    augment_with_integrity asset, pack_type
+  end
+
+  def lookup_pack_with_chunks(name, pack_type = {})
+    assets = super
+
+    assets.map do |asset|
+      augment_with_integrity asset, pack_type
+    end
+  end
+
+  def augment_with_integrity(asset, _pack_type = {})
+    if asset.respond_to?(:dig) && asset['integrity']
+      {src: asset['src'], integrity: asset['integrity']}
+    elsif asset.respond_to?(:dig)
+      asset['src']
+    else
+      asset
+    end
+  end
+end
+
+Webpacker::Manifest.prepend(Webpacker::SriManifestExtensions)