1 files changed, 45 insertions, 0 deletions
diff --git a/app/graphql/resolvers/ci/runner_groups_resolver.rb b/app/graphql/resolvers/ci/runner_groups_resolver.rb
new file mode 100644
index 00000000000..3360e820bd2
--- /dev/null
+++ b/app/graphql/resolvers/ci/runner_groups_resolver.rb
@@ -0,0 +1,45 @@
+# frozen_string_literal: true
+
+module Resolvers
+  module Ci
+    class RunnerGroupsResolver < BaseResolver
+      include Gitlab::Graphql::Authorize::AuthorizeResource
+      include ResolvesGroups
+
+      type Types::GroupConnection, null: true
+
+      authorize :read_runner
+      authorizes_object!
+
+      alias_method :runner, :object
+
+      def resolve_with_lookahead(**args)
+        return unless runner.group_type?
+
+        BatchLoader::GraphQL.for(runner.id).batch(key: :runner_namespaces) do |runner_ids, loader|
+          plucked_runner_and_namespace_ids =
+            ::Ci::RunnerNamespace
+              .for_runner(runner_ids)
+              .select(:runner_id, :namespace_id)
+              .pluck(:runner_id, :namespace_id) # rubocop: disable CodeReuse/ActiveRecord)
+
+          namespace_ids = plucked_runner_and_namespace_ids.collect(&:last).uniq
+          groups = apply_lookahead(::Group.id_in(namespace_ids))
+          Preloaders::GroupPolicyPreloader.new(groups, current_user).execute
+          groups_by_id = groups.index_by(&:id)
+
+          runner_group_ids_by_runner_id =
+            plucked_runner_and_namespace_ids
+              .group_by { |runner_id, _namespace_id| runner_id }
+              .transform_values { |values| values.filter_map { |_runner_id, namespace_id| groups_by_id[namespace_id] } }
+
+          runner_ids.each do |runner_id|
+            runner_namespaces = runner_group_ids_by_runner_id[runner_id] || []
+
+            loader.call(runner_id, runner_namespaces)
+          end
+        end
+      end
+    end
+  end
+end