---
title: Extension APIs
---

# Extension APIs {#extension-apis}

## APIService \[apiregistration.k8s.io/v1\] {#_apiservice_apiregistrationk8siov1}

Description
:   APIService represents a server for a particular GroupVersion. Name must be "version.group".

Type
:   ```
    `object`
    ```

## CustomResourceDefinition \[apiextensions.k8s.io/v1\] {#_customresourcedefinition_apiextensionsk8siov1}

Description
:   CustomResourceDefinition represents a resource that should be exposed on the API server.  Its name MUST be in the format <.spec.name>.<.spec.group>.

Type
:   ```
    `object`
    ```

## MutatingWebhookConfiguration \[admissionregistration.k8s.io/v1\] {#_mutatingwebhookconfiguration_admissionregistrationk8siov1}

Description
:   MutatingWebhookConfiguration describes the configuration of and admission webhook that accept or reject and may change the object.

Type
:   ```
    `object`
    ```

## TestExtensionAdmission \[testextension.redhat.io/v1\] {#_testextensionadmission_testextensionredhatiov1}

Description
:   TestExtensionAdmission controls which ImageStreams are permitted to provide extension test binaries

Type
:   ```
    `object`
    ```

## ValidatingAdmissionPolicy \[admissionregistration.k8s.io/v1\] {#_validatingadmissionpolicy_admissionregistrationk8siov1}

Description
:   ValidatingAdmissionPolicy describes the definition of an admission validation policy that accepts or rejects an object without changing it.

Type
:   ```
    `object`
    ```

## ValidatingAdmissionPolicyBinding \[admissionregistration.k8s.io/v1\] {#_validatingadmissionpolicybinding_admissionregistrationk8siov1}

Description
:   ValidatingAdmissionPolicyBinding binds the ValidatingAdmissionPolicy with paramerized resources. ValidatingAdmissionPolicyBinding and parameter CRDs together define how cluster administrators configure policies for clusters.

    For a given admission request, each binding will cause its policy to be evaluated N times, where N is 1 for policies/bindings that don’t use params, otherwise N is the number of parameters selected by the binding.

    The CEL expressions of a policy must have a computed CEL cost below the maximum CEL budget. Each evaluation of the policy is given an independent CEL cost budget. Adding/removing policies, bindings, or params can not affect whether a given (policy, binding, param) combination is within its own CEL budget.

Type
:   ```
    `object`
    ```

## ValidatingWebhookConfiguration \[admissionregistration.k8s.io/v1\] {#_validatingwebhookconfiguration_admissionregistrationk8siov1}

Description
:   ValidatingWebhookConfiguration describes the configuration of and admission webhook that accept or reject and object without changing it.

Type
:   ```
    `object`
    ```