How to implement our product's custom fields with Looker?

[jbernal]

When I reference custom fields here I mean my company's own product's custom fields that we allow our users to create. I do not mean custom dimensions/measures or table calculations that Looker offers.

We embed looker in our product for customers to create reports and explore their data that is stored and generated via our product. It works great for most of the default fields but we've been unable to establish a user friendly and satisfying solution for the client-specific custom fields. These vary from client to client and rather than each of those custom fields being stored in multiple columns they're stored in one "custom fields" column with a XML object representing all custom fields representing the custom fields populated for that particular record.

Has anyone had any experience or is there any documentation explaining a method for handling how might handle these kinds of fields in Looker/LookML? The ideal goal is that you can have these appear on Looker explores as if they were any other field.