Gracefully handles excluded fields from attributes during serialization

1 files changed, 17 insertions, 2 deletions

diff --git a/lib/gitlab/json_cache.rb b/lib/gitlab/json_cache.rb
index 24daad638f4..e4bc437d787 100644
--- a/lib/gitlab/json_cache.rb
+++ b/lib/gitlab/json_cache.rb
@@ -80,8 +80,23 @@ module Gitlab
       # when the new_record? method incorrectly returns false.
       #
       # See https://gitlab.com/gitlab-org/gitlab-ee/issues/9903#note_145329964
-      attributes = klass.attributes_builder.build_from_database(raw, {})
-      klass.allocate.init_with("attributes" => attributes, "new_record" => new_record?(raw, klass))
+      klass
+        .allocate
+        .init_with(
+          "attributes" => attributes_for(klass, raw),
+          "new_record" => new_record?(raw, klass)
+        )
+    end
+
+    def attributes_for(klass, raw)
+      # We have models that leave out some fields from the JSON export for
+      # security reasons, e.g. models that include the CacheMarkdownField.
+      # The ActiveRecord::AttributeSet we build from raw does know about
+      # these columns so we need manually set them.
+      missing_attributes = (klass.columns.map(&:name) - raw.keys)
+      missing_attributes.each { |column| raw[column] = nil }
+
+      klass.attributes_builder.build_from_database(raw, {})
     end
 
     def new_record?(raw, klass)