Comment 4 for bug 1817313

Looks like the issue is https://github.com/openstack/keystone/blob/f0c2e798f7e706acbaf600bd06521a0e4c514477/keystone/api/os_federation.py#L161 needs to be it's own resource to ensure the protocol ID is required in the routing map, note that the resource object only enforces the first substitution via https://github.com/openstack/keystone/blob/f0c2e798f7e706acbaf600bd06521a0e4c514477/keystone/api/os_federation.py#L482 since it is a "resource".

Alternatively a resource_mapping can be used explicitly for each method allowing the resource object to remain combined.