Upgrade existing Site Column in SharePoint-hosted app

Question

My Scenario:

I have a SharePoint-hosted app with several Lists, Content Types and Site Columns. Now I would like to add some new choices to an existing Site Column (Choice Field).

The Problem:

When upgrading the app, only the Site Column and the Site Content Types are updated. The List Content Types and the List Columns still have the old choices.

The questions:

• Is there a declarative way to push down the changes to the List instances?
• Is there a mechanism to catch the upgrade event to inject custom CSOM code?

Answer 1

All of the SharePoint components that are deployed to the app web are contained in Web-scoped Features in the app package. For that reason, updating these components is a matter of updating one or more of the Features. This process has not changed since SharePoint 2010 and is documented in How to: Add Elements to an Existing Feature in the SharePoint 2010 SDK. Other articles in the Upgrading Features node may be helpful also, but consider that apps must not include custom code on the SharePoint server, so some aspects of Feature upgrading in SharePoint 2010 are not relevant to updating apps. For example, you can't use the CustomUpgradeAction element when you upgrade the Feature of an app for SharePoint.

Reference : https://msdn.microsoft.com/en-us/library/office/dn265911.aspx

Answer 2

According to Steve Curran (MVP) it seems to be impossible to have declarative way of handle the site column lifecycle:

Link to MSDN Forum Entry

In my view Microsoft has to provide a better mechanism than using custom code with every page load.