Service has had a problem since forever:
- User creates a service type=LoadBalancer
- We silently allocate them a NodePort
- User changes type to ClusterIP
- We fail the operation because they did not clear NodePort
They never asked for or used the NodePort!
Dual-stack introduced some dependent fields that get auto-wiped on
updates. This carries it further.
If you squint, you can see Service as a big, messy discriminated union,
with type as the discriminator. Ignoring fields for non-selected
union-modes seems right.
This introduces the potential for an apply loop. Specifically, we will
accept YAML that we did not previously accept. Apply could see the
field in local YAML and not in the server and repeatedly try to patch it
in. But since that YAML is currently an error, it seems like a very low
risk. Almost nobody actually specifies their own NodePort values.
To mitigate this somewhat, we only auto-wipe on updates. The same YAML
would fail to create. This is a little inconsistent. We could
auto-wipe on create, too, at the risk of more potential impact.
To do this properly, we need to know the old and new values, which means
we can not do it in defaulting or conversion. So we do it in strategy.
This change also adds unit tests and updates e2e tests to rely on and
verify this behavior.
* api: structure change
* api: defaulting, conversion, and validation
* [FIX] validation: auto remove second ip/family when service changes to SingleStack
* [FIX] api: defaulting, conversion, and validation
* api-server: clusterIPs alloc, printers, storage and strategy
* [FIX] clusterIPs default on read
* alloc: auto remove second ip/family when service changes to SingleStack
* api-server: repair loop handling for clusterIPs
* api-server: force kubernetes default service into single stack
* api-server: tie dualstack feature flag with endpoint feature flag
* controller-manager: feature flag, endpoint, and endpointSlice controllers handling multi family service
* [FIX] controller-manager: feature flag, endpoint, and endpointSlicecontrollers handling multi family service
* kube-proxy: feature-flag, utils, proxier, and meta proxier
* [FIX] kubeproxy: call both proxier at the same time
* kubenet: remove forced pod IP sorting
* kubectl: modify describe to include ClusterIPs, IPFamilies, and IPFamilyPolicy
* e2e: fix tests that depends on IPFamily field AND add dual stack tests
* e2e: fix expected error message for ClusterIP immutability
* add integration tests for dualstack
the third phase of dual stack is a very complex change in the API,
basically it introduces Dual Stack services. Main changes are:
- It pluralizes the Service IPFamily field to IPFamilies,
and removes the singular field.
- It introduces a new field IPFamilyPolicyType that can take
3 values to express the "dual-stack(mad)ness" of the cluster:
SingleStack, PreferDualStack and RequireDualStack
- It pluralizes ClusterIP to ClusterIPs.
The goal is to add coverage to the services API operations,
taking into account the 6 different modes a cluster can have:
- single stack: IP4 or IPv6 (as of today)
- dual stack: IPv4 only, IPv6 only, IPv4 - IPv6, IPv6 - IPv4
* [FIX] add integration tests for dualstack
* generated data
* generated files
Co-authored-by: Antonio Ojea <aojea@redhat.com>
