This section provides reference information for the Kubernetes API.
The REST API is the fundamental fabric of Kubernetes. All operations and communications between components, and external user commands are REST API calls that the API Server handles. Consequently, everything in the Kubernetes platform is treated as an API object and has a corresponding entry in the API.
The Kubernetes API reference lists the API for Kubernetes version v1.23.
For general background information, read The Kubernetes API. Controlling Access to the Kubernetes API describes how clients can authenticate to the Kubernetes API server, and how their requests are authorized.
The JSON and Protobuf serialization schemas follow the same guidelines for schema changes. The following descriptions cover both formats.
The API versioning and software versioning are indirectly related. The API and release versioning proposal describes the relationship between API versioning and software versioning.
Different API versions indicate different levels of stability and support. You can find more information about the criteria for each level in the API Changes documentation.
Here's a summary of each level:
Alpha:
alpha
(for example, v1alpha1
).Beta:
The version names contain beta
(for example, v2beta3
).
The software is well tested. Enabling a feature is considered safe. Features are enabled by default.
The support for a feature will not be dropped, though the details may change.
The schema and/or semantics of objects may change in incompatible ways in a subsequent beta or stable release. When this happens, migration instructions are provided. Schema changes may require deleting, editing, and re-creating API objects. The editing process may not be straightforward. The migration may require downtime for applications that rely on the feature.
The software is not recommended for production uses. Subsequent releases may introduce incompatible changes. If you have multiple clusters which can be upgraded independently, you may be able to relax this restriction.
Stable:
vX
where X
is an integer.API groups make it easier to extend the Kubernetes API. The API group is specified in a REST path and in the apiVersion
field of a serialized object.
There are several API groups in Kubernetes:
/api/v1
. The core group is not specified as part of the apiVersion
field, for example, apiVersion: v1
./apis/$GROUP_NAME/$VERSION
and use apiVersion: $GROUP_NAME/$VERSION
(for example, apiVersion: batch/v1
). You can find the full list of supported API groups in Kubernetes API reference.Certain resources and API groups are enabled by default. You can enable or disable them by setting --runtime-config
on the API server. The --runtime-config
flag accepts comma separated <key>[=<value>]
pairs describing the runtime configuration of the API server. If the =<value>
part is omitted, it is treated as if =true
is specified. For example:
batch/v1
, set --runtime-config=batch/v1=false
batch/v2alpha1
, set --runtime-config=batch/v2alpha1
--runtime-config
changes. Kubernetes stores its serialized state in terms of the API resources by writing them into etcd.
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Documentation Distributed under CC BY 4.0.
https://kubernetes.io/docs/reference/using-api/