Add `default_branch_name` to ApplicationSettings model

changelogs/unreleased/224447-add-default_branch_name-to-applicationsettings-model.yml

+---
+title: Add default_branch_name to application_setteings
+merge_request: 35282
+author:
+type: other

db/migrate/20200624222443_add_default_branch_name_to_application_settings.rb

+# frozen_string_literal: true
+
+class AddDefaultBranchNameToApplicationSettings < ActiveRecord::Migration[6.0]
+  DOWNTIME = false
+
+  # rubocop:disable Migration/AddLimitToTextColumns
+  # limit is added in db/migrate/20200625190458_add_limit_to_default_branch_name_to_application_settings
+  def change
+    add_column :application_settings, :default_branch_name, :text
+  end
+  # rubocop:enable Migration/AddLimitToTextColumns
+end

db/migrate/20200625190458_add_limit_to_default_branch_name_to_application_settings.rb

+# frozen_string_literal: true
+
+class AddLimitToDefaultBranchNameToApplicationSettings < ActiveRecord::Migration[6.0]
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+
+  disable_ddl_transaction!
+
+  def up
+    add_text_limit :application_settings, :default_branch_name, 255
+  end
+
+  def down
+    remove_text_limit :application_settings, :default_branch_name
+  end
+end

db/structure.sql

@@ -9144,6 +9144,8 @@ CREATE TABLE public.application_settings (
     enforce_pat_expiration boolean DEFAULT true NOT NULL,
     compliance_frameworks smallint[] DEFAULT '{}'::smallint[] NOT NULL,
     notify_on_unknown_sign_in boolean DEFAULT true NOT NULL,
+    default_branch_name text,
+    CONSTRAINT check_51700b31b5 CHECK ((char_length(default_branch_name) <= 255)),
     CONSTRAINT check_d03919528d CHECK ((char_length(container_registry_vendor) <= 255)),
     CONSTRAINT check_d820146492 CHECK ((char_length(spam_check_endpoint_url) <= 255)),
     CONSTRAINT check_e5aba18f02 CHECK ((char_length(container_registry_version) <= 255))
@@ -23452,7 +23454,9 @@ COPY "schema_migrations" (version) FROM STDIN;
 20200623170000
 20200623185440
 20200624075411
+20200624222443
 20200625045442
+20200625190458
 20200626130220
 \.