1 files changed, 150 insertions, 0 deletions
diff --git a/db/migrate/20210621043337_rename_services_to_integrations.rb b/db/migrate/20210621043337_rename_services_to_integrations.rb
new file mode 100644
index 00000000000..17f4b6a2d4d
--- /dev/null
+++ b/db/migrate/20210621043337_rename_services_to_integrations.rb
@@ -0,0 +1,150 @@
+# frozen_string_literal: true
+
+class RenameServicesToIntegrations < ActiveRecord::Migration[6.1]
+  include Gitlab::Database::MigrationHelpers
+  include Gitlab::Database::SchemaHelpers
+
+  # Function and trigger names match those migrated in:
+  # - https://gitlab.com/gitlab-org/gitlab/-/merge_requests/49916
+  # - https://gitlab.com/gitlab-org/gitlab/-/merge_requests/51852
+
+  WIKI_FUNCTION_NAME = 'set_has_external_wiki'
+  TRACKER_FUNCTION_NAME = 'set_has_external_issue_tracker'
+
+  WIKI_TRIGGER_ON_INSERT_NAME = 'trigger_has_external_wiki_on_insert'
+  WIKI_TRIGGER_ON_UPDATE_NAME = 'trigger_has_external_wiki_on_update'
+  WIKI_TRIGGER_ON_DELETE_NAME = 'trigger_has_external_wiki_on_delete'
+
+  TRACKER_TRIGGER_ON_INSERT_NAME = 'trigger_has_external_issue_tracker_on_insert'
+  TRACKER_TRIGGER_ON_UPDATE_NAME = 'trigger_has_external_issue_tracker_on_update'
+  TRACKER_TRIGGER_ON_DELETE_NAME = 'trigger_has_external_issue_tracker_on_delete'
+
+  ALL_TRIGGERS = [
+    WIKI_TRIGGER_ON_INSERT_NAME,
+    WIKI_TRIGGER_ON_UPDATE_NAME,
+    WIKI_TRIGGER_ON_DELETE_NAME,
+    TRACKER_TRIGGER_ON_INSERT_NAME,
+    TRACKER_TRIGGER_ON_UPDATE_NAME,
+    TRACKER_TRIGGER_ON_DELETE_NAME
+  ].freeze
+
+  def up
+    execute('LOCK services IN ACCESS EXCLUSIVE MODE')
+
+    drop_all_triggers(:services)
+
+    rename_table_safely(:services, :integrations)
+
+    recreate_all_triggers(:integrations)
+  end
+
+  def down
+    execute('LOCK integrations IN ACCESS EXCLUSIVE MODE')
+
+    drop_all_triggers(:integrations)
+
+    undo_rename_table_safely(:services, :integrations)
+
+    recreate_all_triggers(:services)
+  end
+
+  private
+
+  def drop_all_triggers(table_name)
+    ALL_TRIGGERS.each do |trigger_name|
+      drop_trigger(table_name, trigger_name)
+    end
+  end
+
+  def recreate_all_triggers(table_name)
+    wiki_create_insert_trigger(table_name)
+    wiki_create_update_trigger(table_name)
+    wiki_create_delete_trigger(table_name)
+
+    tracker_replace_trigger_function(table_name)
+
+    tracker_create_insert_trigger(table_name)
+    tracker_create_update_trigger(table_name)
+    tracker_create_delete_trigger(table_name)
+  end
+
+  def wiki_create_insert_trigger(table_name)
+    execute(<<~SQL)
+      CREATE TRIGGER #{WIKI_TRIGGER_ON_INSERT_NAME}
+      AFTER INSERT ON #{table_name}
+      FOR EACH ROW
+      WHEN (NEW.active = TRUE AND NEW.type = 'ExternalWikiService' AND NEW.project_id IS NOT NULL)
+      EXECUTE FUNCTION #{WIKI_FUNCTION_NAME}();
+    SQL
+  end
+
+  def wiki_create_update_trigger(table_name)
+    execute(<<~SQL)
+      CREATE TRIGGER #{WIKI_TRIGGER_ON_UPDATE_NAME}
+      AFTER UPDATE ON #{table_name}
+      FOR EACH ROW
+      WHEN (NEW.type = 'ExternalWikiService' AND OLD.active != NEW.active AND NEW.project_id IS NOT NULL)
+      EXECUTE FUNCTION #{WIKI_FUNCTION_NAME}();
+    SQL
+  end
+
+  def wiki_create_delete_trigger(table_name)
+    execute(<<~SQL)
+      CREATE TRIGGER #{WIKI_TRIGGER_ON_DELETE_NAME}
+      AFTER DELETE ON #{table_name}
+      FOR EACH ROW
+      WHEN (OLD.type = 'ExternalWikiService' AND OLD.project_id IS NOT NULL)
+      EXECUTE FUNCTION #{WIKI_FUNCTION_NAME}();
+    SQL
+  end
+
+  # Using `replace: true` to rewrite the existing function
+  def tracker_replace_trigger_function(table_name)
+    create_trigger_function(TRACKER_FUNCTION_NAME, replace: true) do
+      <<~SQL
+        UPDATE projects SET has_external_issue_tracker = (
+          EXISTS
+          (
+            SELECT 1
+            FROM #{table_name}
+            WHERE project_id = COALESCE(NEW.project_id, OLD.project_id)
+              AND active = TRUE
+              AND category = 'issue_tracker'
+          )
+        )
+        WHERE projects.id = COALESCE(NEW.project_id, OLD.project_id);
+        RETURN NULL;
+      SQL
+    end
+  end
+
+  def tracker_create_insert_trigger(table_name)
+    execute(<<~SQL)
+      CREATE TRIGGER #{TRACKER_TRIGGER_ON_INSERT_NAME}
+      AFTER INSERT ON #{table_name}
+      FOR EACH ROW
+      WHEN (NEW.category = 'issue_tracker' AND NEW.active = TRUE AND NEW.project_id IS NOT NULL)
+      EXECUTE FUNCTION #{TRACKER_FUNCTION_NAME}();
+    SQL
+  end
+
+  def tracker_create_update_trigger(table_name)
+    execute(<<~SQL)
+      CREATE TRIGGER #{TRACKER_TRIGGER_ON_UPDATE_NAME}
+      AFTER UPDATE ON #{table_name}
+      FOR EACH ROW
+      WHEN (NEW.category = 'issue_tracker' AND OLD.active != NEW.active AND NEW.project_id IS NOT NULL)
+      EXECUTE FUNCTION #{TRACKER_FUNCTION_NAME}();
+    SQL
+  end
+
+  def tracker_create_delete_trigger(table_name)
+    execute(<<~SQL)
+      CREATE TRIGGER #{TRACKER_TRIGGER_ON_DELETE_NAME}
+      AFTER DELETE ON #{table_name}
+      FOR EACH ROW
+      WHEN (OLD.category = 'issue_tracker' AND OLD.active = TRUE AND OLD.project_id IS NOT NULL)
+      EXECUTE FUNCTION #{TRACKER_FUNCTION_NAME}();
+    SQL
+  end
+end