1 files changed, 64 insertions, 0 deletions
diff --git a/rubocop/cop/background_migration/feature_category.rb b/rubocop/cop/background_migration/feature_category.rb
new file mode 100644
index 00000000000..ec70b5baadf
--- /dev/null
+++ b/rubocop/cop/background_migration/feature_category.rb
@@ -0,0 +1,64 @@
+# frozen_string_literal: true
+
+require_relative '../../migration_helpers'
+require_relative '../../code_reuse_helpers'
+
+module RuboCop
+  module Cop
+    module BackgroundMigration
+      # Cop that checks if a valid 'feature_category' is defined in the batched background migration job
+      class FeatureCategory < RuboCop::Cop::Base
+        include MigrationHelpers
+
+        FEATURE_CATEGORIES_FILE_PATH = "config/feature_categories.yml"
+
+        MSG = "'feature_category' should be defined to better assign the ownership for batched migration jobs. " \
+              "For more details refer: " \
+              "https://docs.gitlab.com/ee/development/feature_categorization/#batched-background-migrations"
+
+        INVALID_FEATURE_CATEGORY_MSG = "'feature_category' is invalid. " \
+                                       "List of valid ones can be found in #{FEATURE_CATEGORIES_FILE_PATH}"
+
+        RESTRICT_ON_SEND = [:feature_category].freeze
+
+        class << self
+          attr_accessor :available_feature_categories
+        end
+
+        def_node_search :feature_category?, <<~PATTERN
+          (:send nil? :feature_category ...)
+        PATTERN
+
+        def on_new_investigation
+          super
+
+          # Defined only once per rubocop whole run instead of each file.
+          fetch_available_feature_categories unless self.class.available_feature_categories.present?
+        end
+
+        def on_class(node)
+          return unless in_background_migration?(node) && node.parent_class&.short_name == :BatchedMigrationJob
+
+          add_offense(node) unless feature_category?(node)
+        end
+
+        def on_send(node)
+          return unless in_background_migration?(node)
+
+          add_offense(node, message: INVALID_FEATURE_CATEGORY_MSG) unless valid_feature_category?(node)
+        end
+
+        private
+
+        def valid_feature_category?(node)
+          feature_category = node.descendants.first.value
+          self.class.available_feature_categories.include?(feature_category.to_s)
+        end
+
+        def fetch_available_feature_categories
+          self.class.available_feature_categories = YAML.load_file(FEATURE_CATEGORIES_FILE_PATH).to_set
+        end
+      end
+    end
+  end
+end