Appengine ProtoRPC cache-control headers

Question

Is it possible to set cache-control headers when using AppEngine's ProtoRPC library?

If I query my service I can see it is currently setting a no-cache header:

HTTP/1.1 200 OK
content-type: application/json
Cache-Control: no-cache
Expires: Fri, 01 Jan 1990 00:00:00 GMT
Content-Length: 2
Server: Development/2.0
Date: Thu, 20 Feb 2014 11:47:48 GMT

I haven't been able to find any way to change it, although the Endpoints library does seem to allow control of the cache headers, and I know it's built on ProtoRPC, so presumably it can be done.

Answer 1

To answer my own question, it seems this is not possible.

There are hooks in the Cloud Endpoints code to change the cache-control, but they are stubs, not yet implemented: https://code.google.com/p/googleappengine/issues/detail?id=9042

ProtoRPC does not yet support it either: https://groups.google.com/forum/#!topic/google-appengine-python/l43R6w_3mpM