DEV: Plugin API to add directory columns (#13440)

db/migrate/20210618135229_reintroduce_type_to_directory_columns.rb

@@ -0,0 +1,22 @@
+# frozen_string_literal: true
+
+class ReintroduceTypeToDirectoryColumns < ActiveRecord::Migration[6.1]
+  def up
+    if !ActiveRecord::Base.connection.column_exists?(:directory_columns, :type)
+      # A migration that added this column was previously merged and reverted.
+      # Some sites have this column and some do not, so only add if missing.
+      add_column :directory_columns, :type, :integer, default: 0, null: false
+    end
+
+    DB.exec(
+      <<~SQL
+        UPDATE directory_columns
+        SET type = CASE WHEN automatic THEN 0 ELSE 1 END;
+      SQL
+    )
+  end
+
+  def down
+    remove_column :directory_columns, :type
+  end
+end