<!--{
	"Title": "The Go Programming Language Specification",
	"Subtitle": "Language version go1.22 (April 25, 2024)",
	"Path": "/ref/spec"
}-->

<h2 id="Introduction">Introduction</h2>

<p>
This is the reference manual for the Go programming language.
The pre-Go1.18 version, without generics, can be found
<a href="/doc/go1.17_spec.html">here</a>.
For more information and other documents, see <a href="/">go.dev</a>.
</p>

<p>

  // - spec.hostPID
  // - spec.hostIPC
  // - spec.hostUsers
  // - spec.securityContext.seLinuxOptions
  // - spec.securityContext.seccompProfile
  // - spec.securityContext.fsGroup
  // - spec.securityContext.fsGroupChangePolicy
  // - spec.securityContext.sysctls
  // - spec.shareProcessNamespace
  // - spec.securityContext.runAsUser

  - `spec.scope` is no longer defaulted to `Namespaced` and must be explicitly specified
  - `spec.version` is removed in v1; use `spec.versions` instead
  - `spec.validation` is removed in v1; use `spec.versions[*].schema` instead
  - `spec.subresources` is removed in v1; use `spec.versions[*].subresources` instead
  - `spec.additionalPrinterColumns` is removed in v1; use `spec.versions[*].additionalPrinterColumns` instead

#### Behavioral Changes

 - For all kinds in the API group version, a spec.selector default value is no longer
 available, because it's incompatible with `kubectl
 apply` and strategic merge patch. You must explicitly set the spec.selector value
 in your manifest. An object with a spec.selector value that does not match the labels in
 its spec.template is invalid.

 - Selector mutation is disabled for all kinds in the

- When using `kubectl replace` (or the equivalent API call) on a Service, the caller no longer needs to do a read-modify-write cycle to fetch the allocated values for `.spec.clusterIP` and `.spec.ports[].nodePort`.  Instead the API server will automatically carry these forward from the original object when the new object does not specify them. ([#104673](https://github.com/kubernetes/kubernetes/pull/104673), [@thockin](https://github.com/thockin))...

  - If the custom resource participates the spec/status convention, the metadata.generation of the CR increments when there is any change, except for the changes to the metadata or the changes to the status.
  - If the custom resource does not participate the spec/status convention, the metadata.generation of the CR increments when there is any change to the CR, except for changes to the metadata.

- Pods which have an invalid negative `spec.terminationGracePeriodSeconds` value will be treated as having terminationGracePeriodSeconds of 1 ([#115606](https://github.com/kubernetes/kubernetes/pull/115606), [@wzshiming](https://github.com/wzshiming)) [SIG Apps, Node and Testing]

- When using `kubectl replace` (or the equivalent API call) on a Service, the caller no longer needs to do a read-modify-write cycle to fetch the allocated values for `.spec.clusterIP` and `.spec.ports[].nodePort`.  Instead the API server will automatically carry these forward from the original object when the new object does not specify them. ([#104672](https://github.com/kubernetes/kubernetes/pull/104672), [@thockin](https://github.com/thockin))...

*   The `volume.beta.kubernetes.io/storage-class` annotation is deprecated. It will be removed in a future release. For the StorageClass API object, use v1, and in place of the annotation use `v1.PersistentVolumeClaim.Spec.StorageClassName` and `v1.PersistentVolume.Spec.StorageClassName` instead. ([#53580](https://github.com/kubernetes/kubernetes/pull/53580),[ @xiangpengzhao](https://github.com/xiangpengzhao))

### **Scheduling**

* The `spec.SecurityContext.Sysctls` field is now dropped during creation of `Pod` objects unless the `Sysctls` feature gate is enabled. ([#72752](https://github.com/kubernetes/kubernetes/pull/72752), [@rajathagasthya](https://github.com/rajathagasthya))