Problem/Motivation

Add more flexibility in how we show data in an index. This data can come from sources outside of the Drupal site. This data is also not necessarily indexed by a Drupal application.

To support this in Search API we need to rethink how the architecture expects data to come in to the system. We should no longer rely on only entities from the current Drupal site if we want to support multisite.

Proposed resolution

Not sure yet

Remaining tasks

Unidentified

User interface changes

Unidentified

API changes

Unidentified

Comments

We should no longer rely on only entities from the current Drupal site if we want to support multisite.

As said, we already don't. Furthermore, with the SearchApiExternalDataSourceController we already provide a good base, I think, for defining item types for such externally indexed data.
However, we can of course vet this system on how well this is really supported, what could be improved and maybe add an implementation already to the Solr module which we could then use for such tests.
#2044419: Make datasource controllers more powerful should further help with this.