Merge branch 'sh-fix-webpack-and-thin' into 'master'

Fix Webpack manifest not working with single-threaded Web servers

See merge request gitlab-org/gitlab!43781

config/initializers/static_files.rb

@@ -21,12 +21,12 @@ if app.config.public_file_server.enabled
     settings = {
       enabled: true,
       host: dev_server.host,
+      manifest_host: dev_server.host,
+      manifest_port: dev_server.port,
       port: dev_server.port
     }
 
     if Rails.env.development?
-      # /assets are proxied through a Rails middlware to the Webpack
-      # server, so we have to use the local Rails settings.
       settings.merge!(
         host: Gitlab.config.gitlab.host,
         port: Gitlab.config.gitlab.port,

lib/gitlab/webpack/manifest.rb

@@ -88,10 +88,9 @@ module Gitlab
         end
 
         def load_dev_server_manifest
-          host = ::Rails.configuration.webpack.dev_server.host
-          port = ::Rails.configuration.webpack.dev_server.port
-          scheme = ::Rails.configuration.webpack.dev_server.https ? 'https' : 'http'
-          uri = Addressable::URI.new(scheme: scheme, host: host, port: port, path: dev_server_path)
+          host = ::Rails.configuration.webpack.dev_server.manifest_host
+          port = ::Rails.configuration.webpack.dev_server.manifest_port
+          uri = Addressable::URI.new(scheme: 'http', host: host, port: port, path: dev_server_path)
 
           # localhost could be blocked via Gitlab::HTTP
           response = HTTParty.get(uri.to_s, verify: false) # rubocop:disable Gitlab/HTTParty

spec/lib/gitlab/webpack/manifest_spec.rb

@@ -41,7 +41,9 @@ RSpec.describe Gitlab::Webpack::Manifest do
   before do
     # Test that config variables work while we're here
     ::Rails.configuration.webpack.dev_server.host = 'hostname'
-    ::Rails.configuration.webpack.dev_server.port = 2000
+    ::Rails.configuration.webpack.dev_server.port = 1999
+    ::Rails.configuration.webpack.dev_server.manifest_host = 'hostname'
+    ::Rails.configuration.webpack.dev_server.manifest_port = 2000
     ::Rails.configuration.webpack.manifest_filename = "my_manifest.json"
     ::Rails.configuration.webpack.public_path = "public_path"
     ::Rails.configuration.webpack.output_dir = "manifest_output"