1 files changed, 52 insertions, 14 deletions

diff --git a/lib/gitlab/pages/cache_control.rb b/lib/gitlab/pages/cache_control.rb
index 187d5f907e4..be39e52b342 100644
--- a/lib/gitlab/pages/cache_control.rb
+++ b/lib/gitlab/pages/cache_control.rb
@@ -1,5 +1,7 @@
 # frozen_string_literal: true
 
+require 'set'
+
 module Gitlab
   module Pages
     class CacheControl
@@ -9,7 +11,9 @@ module Gitlab
       # To avoid delivering expired deployment URL in the cached payload,
       # use a longer expiration time in the deployment URL
       DEPLOYMENT_EXPIRATION = (EXPIRE + 12.hours)
-      CACHE_KEY_FORMAT = 'pages_domain_for_%{type}_%{id}_%{settings}'
+
+      SETTINGS_CACHE_KEY = 'pages_domain_for_%{type}_%{id}'
+      PAYLOAD_CACHE_KEY = '%{settings_cache_key}_%{settings_hash}'
 
       class << self
         def for_project(project_id)
@@ -29,29 +33,63 @@ module Gitlab
       end
 
       def cache_key
-        strong_memoize(:cache_key) do
-          CACHE_KEY_FORMAT % {
-            type: @type,
-            id: @id,
-            settings: settings
-          }
+        strong_memoize(:payload_cache_key) do
+          cache_settings_hash!
+
+          payload_cache_key_for(settings_hash)
         end
       end
 
+      # Invalidates the cache.
+      #
+      # Since rails nodes and sidekiq nodes have different application settings,
+      # and the invalidation happens in a sidekiq node, we have to use the
+      # cached settings hash to build the payload cache key to be invalidated.
       def clear_cache
-        Rails.cache.delete(cache_key)
+        keys = cached_settings_hashes
+          .map { |hash| payload_cache_key_for(hash) }
+          .push(settings_cache_key)
+
+        Rails.cache.delete_multi(keys)
       end
 
       private
 
-      def settings
-        values = ::Gitlab.config.pages.dup
+      # Since rails nodes and sidekiq nodes have different application settings,
+      # we cache the application settings hash when creating the payload cache
+      # so we can use these values to invalidate the cache in a sidekiq node later.
+      def cache_settings_hash!
+        cached = cached_settings_hashes.to_set
+        Rails.cache.write(settings_cache_key, cached.add(settings_hash))
+      end
+
+      def cached_settings_hashes
+        Rails.cache.read(settings_cache_key) || []
+      end
+
+      def payload_cache_key_for(settings_hash)
+        PAYLOAD_CACHE_KEY % {
+          settings_cache_key: settings_cache_key,
+          settings_hash: settings_hash
+        }
+      end
 
-        values['app_settings'] = ::Gitlab::CurrentSettings.attributes.slice(
-          'force_pages_access_control'
-        )
+      def settings_cache_key
+        strong_memoize(:settings_cache_key) do
+          SETTINGS_CACHE_KEY % { type: @type, id: @id }
+        end
+      end
 
-        ::Digest::SHA256.hexdigest(values.inspect)
+      def settings_hash
+        strong_memoize(:settings_hash) do
+          values = ::Gitlab.config.pages.dup
+
+          values['app_settings'] = ::Gitlab::CurrentSettings.attributes.slice(
+            'force_pages_access_control'
+          )
+
+          ::Digest::SHA256.hexdigest(values.inspect)
+        end
       end
     end
   end