Fix initialization and add download endpoint [SCI-9465]

app/controllers/asset_sync_controller.rb

@@ -1,9 +1,9 @@
 # frozen_string_literal: true
 
 class AssetSyncController < ApplicationController
-  skip_before_action :authenticate_user!, only: :update
-  skip_before_action :verify_authenticity_token, only: :update
-  before_action :authenticate_asset_sync_token!, only: :update
+  skip_before_action :authenticate_user!, only: %i(update download)
+  skip_before_action :verify_authenticity_token, only: %i(update download)
+  before_action :authenticate_asset_sync_token!, only: %i(update download)
 
   def show
     asset = Asset.find_by(id: params[:asset_id])
@@ -19,6 +19,10 @@ class AssetSyncController < ApplicationController
     render json: AssetSyncTokenSerializer.new(asset_sync_token).as_json
   end
 
+  def download
+    redirect_to @asset.file.url
+  end
+
   def update
     head(:conflict) and return if @asset_sync_token.conflicts?(request.headers['VersionToken'])
 

app/serializers/asset_sync_token_serializer.rb

@@ -10,7 +10,7 @@ class AssetSyncTokenSerializer < ActiveModel::Serializer
   end
 
   def url
-    object.asset.file.url
+    asset_sync_download_url(asset_id: object.asset)
   end
 
   def filename

config/initializers/extends.rb

@@ -610,7 +610,9 @@ class Extends
     www.gstatic.com/recaptcha/
   )
 
-  EXTERNAL_SERVICES << Constants::ASSET_SYNC_URL unless EXTERNAL_SERVICES.include?(Constants::ASSET_SYNC_URL)
+  if Constants::ASSET_SYNC_URL && EXTERNAL_SERVICES.exclude?(Constants::ASSET_SYNC_URL)
+    EXTERNAL_SERVICES << Constants::ASSET_SYNC_URL
+  end
 
   COLORED_BACKGROUND_ACTIONS = %w(
     my_modules/protocols

config/routes.rb

@@ -1003,6 +1003,7 @@ Rails.application.routes.draw do
   end
 
   get 'asset_sync/:asset_id', to: 'asset_sync#show', as: :asset_sync_show
+  get 'asset_sync/:asset_id/download', to: 'asset_sync#download', as: :asset_sync_download
   put 'asset_sync', to: 'asset_sync#update'
 
   post 'global_activities', to: 'global_activities#index'