Multi-tagging of HTTP cache (EZP-25696) makes resource embedding with working cache possible.

Any REST response that embeds resources will need to add the appropriate cache headers so that it gets purged along with the referenced (embedded) objects: a Content response with its Section embedded must be cleared when the given section is edited.

Since references are loaded using their own controller, any change should transparently work with the main object's resource, but it needs to be tested.

In addition to cache tags, the response's Vary header must contain the X-eZ-Embed-Value that was used to customize the response.