Allow configuration in some manner to call an API to retrieve a property. For example, if I had an internal application which had an API that allows me to query for location information about a facility when I provide a facility ID and desired parameter to be returned, I'd like to somehow be able to have Canary use that API.

To my current understanding, an external SQL database is the only external method available to configure properties.

This primarily has use in larger organizations that would have an internal services with an API that they could query for this information, but there could be scenarios with other data providers where being able to query an external API to retrieve relevant metadata could be useful.