1 files changed, 27 insertions, 0 deletions
diff --git a/lib/gitlab/webpack/manifest.rb b/lib/gitlab/webpack/manifest.rb
new file mode 100644
index 00000000000..0c343e5bc1d
--- /dev/null
+++ b/lib/gitlab/webpack/manifest.rb
@@ -0,0 +1,27 @@
+require 'webpack/rails/manifest'
+
+module Gitlab
+  module Webpack
+    class Manifest < ::Webpack::Rails::Manifest
+      # Raised if a supplied asset does not exist in the webpack manifest
+      AssetMissingError = Class.new(StandardError)
+
+      class << self
+        def entrypoint_paths(source)
+          raise ::Webpack::Rails::Manifest::WebpackError, manifest["errors"] unless manifest_bundled?
+
+          entrypoint = manifest["entrypoints"][source]
+          if entrypoint && entrypoint["assets"]
+            # Can be either a string or an array of strings.
+            # Do not include source maps as they are not javascript
+            [entrypoint["assets"]].flatten.reject { |p| p =~ /.*\.map$/ }.map do |p|
+              "/#{::Rails.configuration.webpack.public_path}/#{p}"
+            end
+          else
+            raise AssetMissingError, "Can't find entry point '#{source}' in webpack manifest"
+          end
+        end
+      end
+    end
+  end
+end