MutatingAdmissionPolicy
admissionregistration.k8s.io/v1
Cluster
MutatingAdmissionPolicy describes the definition of an admission mutation policy that mutates the object coming into admission chain.
RBAC Verbs
create
delete
deletecollection
get
list
patch
update
watch
Properties
| Field | Type | Required? | Description |
|---|---|---|---|
| apiVersion | string | APIVersion defines the versioned schema of this representation of an object. Servers should convert recognized schemas to the latest internal value, and may reject unrecognized values. More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#resources |
| Field | Type | Required? | Description |
|---|---|---|---|
| kind | string | Kind is a string value representing the REST resource this object represents. Servers may infer this from the endpoint the client submits requests to. Cannot be updated. In CamelCase. More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#types-kinds |
| Field | Type | Required? | Description |
|---|---|---|---|
| metadata | object | metadata is the standard object metadata; More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#metadata. | |
| metadata.annotations | object | Annotations is an unstructured key value map stored with a resource that may be set by external tools to store and retrieve arbitrary metadata. They are not queryable and should be preserved when modifying objects. More info: https://kubernetes.io/docs/concepts/overview/working-with-objects/annotations | |
| metadata.creationTimestamp | string | CreationTimestamp is a timestamp representing the server time when this object was created. It is not guaranteed to be set in happens-before order across separate operations. Clients may not set this value. It is represented in RFC3339 form and is in UTC. Populated by the system. Read-only. Null for lists. More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#metadata | |
| metadata.deletionGracePeriodSeconds | integer | Number of seconds allowed for this object to gracefully terminate before it will be removed from the system. Only set when deletionTimestamp is also set. May only be shortened. Read-only. | |
| metadata.deletionTimestamp | string | DeletionTimestamp is RFC 3339 date and time at which this resource will be deleted. This field is set by the server when a graceful deletion is requested by the user, and is not directly settable by a client. The resource is expected to be deleted (no longer visible from resource lists, and not reachable by name) after the time in this field, once the finalizers list is empty. As long as the finalizers list contains items, deletion is blocked. Once the deletionTimestamp is set, this value may not be unset or be set further into the future, although it may be shortened or the resource may be deleted prior to this time. For example, a user may request that a pod is deleted in 30 seconds. The Kubelet will react by sending a graceful termination signal to the containers in the pod. After that 30 seconds, the Kubelet will send a hard termination signal (SIGKILL) to the container and after cleanup, remove the pod from the API. In the presence of network partitions, this object may still exist after this timestamp, until an administrator or automated process can determine the resource is fully terminated. If not set, graceful deletion of the object has not been requested. Populated by the system when a graceful deletion is requested. Read-only. More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#metadata | |
| metadata.finalizers | array | Must be empty before the object is deleted from the registry. Each entry is an identifier for the responsible component that will remove the entry from the list. If the deletionTimestamp of the object is non-nil, entries in this list can only be removed. Finalizers may be processed and removed in any order. Order is NOT enforced because it introduces significant risk of stuck finalizers. finalizers is a shared field, any actor with permission can reorder it. If the finalizer list is processed in order, then this can lead to a situation in which the component responsible for the first finalizer in the list is waiting for a signal (field value, external system, or other) produced by a component responsible for a finalizer later in the list, resulting in a deadlock. Without enforced ordering finalizers are free to order amongst themselves and are not vulnerable to ordering changes in the list. | |
| metadata.generateName | string | GenerateName is an optional prefix, used by the server, to generate a unique name ONLY IF the Name field has not been provided. If this field is used, the name returned to the client will be different than the name passed. This value will also be combined with a unique suffix. The provided value has the same validation rules as the Name field, and may be truncated by the length of the suffix required to make the value unique on the server. If this field is specified and the generated name exists, the server will return a 409. Applied only if Name is not specified. More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#idempotency | |
| metadata.generation | integer | A sequence number representing a specific generation of the desired state. Populated by the system. Read-only. | |
| metadata.labels | object | Map of string keys and values that can be used to organize and categorize (scope and select) objects. May match selectors of replication controllers and services. More info: https://kubernetes.io/docs/concepts/overview/working-with-objects/labels | |
| metadata.managedFields | array | ManagedFields maps workflow-id and version to the set of fields that are managed by that workflow. This is mostly for internal housekeeping, and users typically shouldn't need to set or understand this field. A workflow can be the user's name, a controller's name, or the name of a specific apply path like "ci-cd". The set of fields is always in the version that the workflow used when modifying the object. | |
| metadata.name | string | Name must be unique within a namespace. Is required when creating resources, although some resources may allow a client to request the generation of an appropriate name automatically. Name is primarily intended for creation idempotence and configuration definition. Cannot be updated. More info: https://kubernetes.io/docs/concepts/overview/working-with-objects/names#names | |
| metadata.namespace | string | Namespace defines the space within which each name must be unique. An empty namespace is equivalent to the "default" namespace, but "default" is the canonical representation. Not all objects are required to be scoped to a namespace - the value of this field for those objects will be empty. Must be a DNS_LABEL. Cannot be updated. More info: https://kubernetes.io/docs/concepts/overview/working-with-objects/namespaces | |
| metadata.ownerReferences | array | List of objects depended by this object. If ALL objects in the list have been deleted, this object will be garbage collected. If this object is managed by a controller, then an entry in this list will point to this controller, with the controller field set to true. There cannot be more than one managing controller. | |
| metadata.resourceVersion | string | An opaque value that represents the internal version of this object that can be used by clients to determine when objects have changed. May be used for optimistic concurrency, change detection, and the watch operation on a resource or set of resources. Clients must treat these values as opaque and passed unmodified back to the server. They may only be valid for a particular resource or set of resources. Populated by the system. Read-only. Value must be treated as opaque by clients and . More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#concurrency-control-and-consistency | |
| metadata.selfLink | string | Deprecated: selfLink is a legacy read-only field that is no longer populated by the system. | |
| metadata.uid | string | UID is the unique in time and space value for this object. It is typically generated by the server on successful creation of a resource and is not allowed to change on PUT operations. Populated by the system. Read-only. More info: https://kubernetes.io/docs/concepts/overview/working-with-objects/names#uids |
| Field | Type | Required? | Description |
|---|---|---|---|
| spec | object | spec defines the desired behavior of the MutatingAdmissionPolicy. | |
| spec.failurePolicy | string | failurePolicy defines how to handle failures for the admission policy. Failures can occur from CEL expression parse errors, type check errors, runtime errors and invalid or mis-configured policy definitions or bindings. A policy is invalid if paramKind refers to a non-existent Kind. A binding is invalid if paramRef.name refers to a non-existent resource. failurePolicy does not define how validations that evaluate to false are handled. Allowed values are Ignore or Fail. Defaults to Fail. | |
| spec.matchConditions | array | matchConditions is a list of conditions that must be met for a request to be validated. Match conditions filter requests that have already been matched by the matchConstraints. An empty list of matchConditions matches all requests. There are a maximum of 64 match conditions allowed. If a parameter object is provided, it can be accessed via the `params` handle in the same manner as validation expressions. The exact matching logic is (in order): 1. If ANY matchCondition evaluates to FALSE, the policy is skipped. 2. If ALL matchConditions evaluate to TRUE, the policy is evaluated. 3. If any matchCondition evaluates to an error (but none are FALSE): - If failurePolicy=Fail, reject the request - If failurePolicy=Ignore, the policy is skipped | |
| spec.matchConstraints | object | matchConstraints specifies what resources this policy is designed to validate. The MutatingAdmissionPolicy cares about a request if it matches _all_ Constraints. However, in order to prevent clusters from being put into an unstable state that cannot be recovered from via the API MutatingAdmissionPolicy cannot match MutatingAdmissionPolicy and MutatingAdmissionPolicyBinding. The CREATE, UPDATE and CONNECT operations are allowed. The DELETE operation may not be matched. '*' matches CREATE, UPDATE and CONNECT. Required. | |
| spec.matchConstraints.excludeResourceRules | array | excludeResourceRules describes what operations on what resources/subresources the ValidatingAdmissionPolicy should not care about. The exclude rules take precedence over include rules (if a resource matches both, it is excluded) | |
| spec.matchConstraints.matchPolicy | string | matchPolicy defines how the "MatchResources" list is used to match incoming requests. Allowed values are "Exact" or "Equivalent". - Exact: match a request only if it exactly matches a specified rule. For example, if deployments can be modified via apps/v1, apps/v1beta1, and extensions/v1beta1, but "rules" only included `apiGroups:["apps"], apiVersions:["v1"], resources: ["deployments"]`, a request to apps/v1beta1 or extensions/v1beta1 would not be sent to the ValidatingAdmissionPolicy. - Equivalent: match a request if modifies a resource listed in rules, even via another API group or version. For example, if deployments can be modified via apps/v1, apps/v1beta1, and extensions/v1beta1, and "rules" only included `apiGroups:["apps"], apiVersions:["v1"], resources: ["deployments"]`, a request to apps/v1beta1 or extensions/v1beta1 would be converted to apps/v1 and sent to the ValidatingAdmissionPolicy. Defaults to "Equivalent" | |
| spec.matchConstraints.namespaceSelector | object | namespaceSelector decides whether to run the admission control policy on an object based on whether the namespace for that object matches the selector. If the object itself is a namespace, the matching is performed on object.metadata.labels. If the object is another cluster scoped resource, it never skips the policy. For example, to run the webhook on any objects whose namespace is not associated with "runlevel" of "0" or "1"; you will set the selector as follows: "namespaceSelector": { "matchExpressions": [ { "key": "runlevel", "operator": "NotIn", "values": [ "0", "1" ] } ] } If instead you want to only run the policy on any objects whose namespace is associated with the "environment" of "prod" or "staging"; you will set the selector as follows: "namespaceSelector": { "matchExpressions": [ { "key": "environment", "operator": "In", "values": [ "prod", "staging" ] } ] } See https://kubernetes.io/docs/concepts/overview/working-with-objects/labels/ for more examples of label selectors. Default to the empty LabelSelector, which matches everything. | |
| spec.matchConstraints.namespaceSelector.matchExpressions | array | matchExpressions is a list of label selector requirements. The requirements are ANDed. | |
| spec.matchConstraints.namespaceSelector.matchLabels | object | matchLabels is a map of {key,value} pairs. A single {key,value} in the matchLabels map is equivalent to an element of matchExpressions, whose key field is "key", the operator is "In", and the values array contains only "value". The requirements are ANDed. | |
| spec.matchConstraints.objectSelector | object | objectSelector decides whether to run the validation based on if the object has matching labels. objectSelector is evaluated against both the oldObject and newObject that would be sent to the cel validation, and is considered to match if either object matches the selector. A null object (oldObject in the case of create, or newObject in the case of delete) or an object that cannot have labels (like a DeploymentRollback or a PodProxyOptions object) is not considered to match. Use the object selector only if the webhook is opt-in, because end users may skip the admission webhook by setting the labels. Default to the empty LabelSelector, which matches everything. | |
| spec.matchConstraints.objectSelector.matchExpressions | array | matchExpressions is a list of label selector requirements. The requirements are ANDed. | |
| spec.matchConstraints.objectSelector.matchLabels | object | matchLabels is a map of {key,value} pairs. A single {key,value} in the matchLabels map is equivalent to an element of matchExpressions, whose key field is "key", the operator is "In", and the values array contains only "value". The requirements are ANDed. | |
| spec.matchConstraints.resourceRules | array | resourceRules describes what operations on what resources/subresources the ValidatingAdmissionPolicy matches. The policy cares about an operation if it matches _any_ Rule. | |
| spec.mutations | array | mutations contain operations to perform on matching objects. mutations may not be empty; a minimum of one mutation is required. mutations are evaluated in order, and are reinvoked according to the reinvocationPolicy. The mutations of a policy are invoked for each binding of this policy and reinvocation of mutations occurs on a per binding basis. | |
| spec.paramKind | object | paramKind specifies the kind of resources used to parameterize this policy. If absent, there are no parameters for this policy and the param CEL variable will not be provided to validation expressions. If paramKind refers to a non-existent kind, this policy definition is mis-configured and the FailurePolicy is applied. If paramKind is specified but paramRef is unset in MutatingAdmissionPolicyBinding, the params variable will be null. | |
| spec.paramKind.apiVersion | string | apiVersion is the API group version the resources belong to. In format of "group/version". Required. | |
| spec.paramKind.kind | string | kind is the API kind the resources belong to. Required. | |
| spec.reinvocationPolicy | string | reinvocationPolicy indicates whether mutations may be called multiple times per MutatingAdmissionPolicyBinding as part of a single admission evaluation. Allowed values are "Never" and "IfNeeded". Never: These mutations will not be called more than once per binding in a single admission evaluation. IfNeeded: These mutations may be invoked more than once per binding for a single admission request and there is no guarantee of order with respect to other admission plugins, admission webhooks, bindings of this policy and admission policies. Mutations are only reinvoked when mutations change the object after this mutation is invoked. Required. | |
| spec.variables | array | variables contain definitions of variables that can be used in composition of other expressions. Each variable is defined as a named CEL expression. The variables defined here will be available under `variables` in other expressions of the policy except matchConditions because matchConditions are evaluated before the rest of the policy. The expression of a variable can refer to other variables defined earlier in the list but not those after. Thus, variables must be sorted by the order of first appearance and acyclic. |
Sample Manifest
Minimal example generated from required fields — not hand-verified.
apiVersion: admissionregistration.k8s.io/v1
kind: MutatingAdmissionPolicy
metadata:
name: my-mutatingadmissionpolicy
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