Use shared informers instead of creating local controllers/reflectors
for the proxy's endpoints and service configs. This allows downstream
integrators to pass in preexisting shared informers to save on memory &
cpu usage.
This also enables the cache mutation detector for kube-proxy for those
presubmit jobs that already turn it on.
Refactor `pkg/proxy/config`’s ServiceConfigHandler.OnUpdate and
EndpointsConfigHandler.OnUpdate to different method names as they have
different signatures.
This will let the new proxy
(https://github.com/GoogleCloudPlatform/kubernetes/issues/3760)
implement both interfaces.
Since we won’t need a separate loadbalancer structure (load balancing
is handled in the proxy rules), we will simply handle both event types
from the same object.
Instead of endpoints being a flat list, it is now a list of "subsets"
where each is a struct of {Addresses, Ports}. To generate the list of
endpoints you need to take union of the Cartesian products of the
subsets. This is compact in the vast majority of cases, yet still
represents named ports and corner cases (e.g. each pod has a different
port number).
This also stores subsets in a deterministic order (sorted by hash) to
avoid spurious updates and comparison problems.
This is a fully compatible change - old objects and clients will
keepworking as long as they don't need the new functionality.
This is the prep for multi-port Services, which will add API to produce
endpoints in this new structure.
Splits endpoint and service configuration into their own objects. Also makes
the endpoint and service configuration tests correct - there was a race condition
previously that meant tests were passing but not checking correct code.
