Revert "Revert "Merge branch 'ee-5481-epic-todos' into 'master'""

This reverts commit 8717c7dad9b5a8fa21ec9a652c54718a6b4c2175.

1 files changed, 32 insertions, 0 deletions

diff --git a/db/migrate/20180608091413_add_group_to_todos.rb b/db/migrate/20180608091413_add_group_to_todos.rb
new file mode 100644
index 00000000000..af3ee48b29d
--- /dev/null
+++ b/db/migrate/20180608091413_add_group_to_todos.rb
@@ -0,0 +1,32 @@
+class AddGroupToTodos < ActiveRecord::Migration
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+
+  disable_ddl_transaction!
+
+  def up
+    add_column :todos, :group_id, :integer
+    add_concurrent_foreign_key :todos, :namespaces, column: :group_id, on_delete: :cascade
+    add_concurrent_index :todos, :group_id
+
+    change_column_null :todos, :project_id, true
+  end
+
+  def down
+    return unless group_id_exists?
+
+    remove_foreign_key :todos, column: :group_id
+    remove_index :todos, :group_id if index_exists?(:todos, :group_id)
+    remove_column :todos, :group_id
+
+    execute "DELETE FROM todos WHERE project_id IS NULL"
+    change_column_null :todos, :project_id, false
+  end
+
+  private
+
+  def group_id_exists?
+    column_exists?(:todos, :group_id)
+  end
+end