Description

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

Type

object

Specification

Property Type 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

.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

.metadata

ObjectMeta meta/v1

Standard object metadata; More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#metadata.

.webhooks

array

Webhooks is a list of webhooks and the affected resources and operations.

.webhooks[]

object

ValidatingWebhook describes an admission webhook and the resources and operations it applies to.

.webhooks
Description

Webhooks is a list of webhooks and the affected resources and operations.

Type

array

.webhooks[]
Description

ValidatingWebhook describes an admission webhook and the resources and operations it applies to.

Type

object

Required
  • name

  • clientConfig

  • sideEffects

  • admissionReviewVersions

Property Type Description

admissionReviewVersions

array (string)

AdmissionReviewVersions is an ordered list of preferred AdmissionReview versions the Webhook expects. API server will try to use first version in the list which it supports. If none of the versions specified in this list supported by API server, validation will fail for this object. If a persisted webhook configuration specifies allowed versions and does not include any versions known to the API Server, calls to the webhook will fail and be subject to the failure policy.

clientConfig

object

WebhookClientConfig contains the information to make a TLS connection with the webhook

failurePolicy

string

FailurePolicy defines how unrecognized errors from the admission endpoint are handled - allowed values are Ignore or Fail. Defaults to Fail.

matchPolicy

string

matchPolicy defines how the "rules" 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 webhook.

- 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 webhook.

Defaults to "Equivalent"

name

string

The name of the admission webhook. Name should be fully qualified, e.g., imagepolicy.kubernetes.io, where "imagepolicy" is the name of the webhook, and kubernetes.io is the name of the organization. Required.

namespaceSelector

LabelSelector meta/v1

NamespaceSelector decides whether to run the webhook 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 webhook.

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 webhook 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.

objectSelector

LabelSelector meta/v1

ObjectSelector decides whether to run the webhook based on if the object has matching labels. objectSelector is evaluated against both the oldObject and newObject that would be sent to the webhook, 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.

rules

array

Rules describes what operations on what resources/subresources the webhook cares about. The webhook cares about an operation if it matches any Rule. However, in order to prevent ValidatingAdmissionWebhooks and MutatingAdmissionWebhooks from putting the cluster in a state which cannot be recovered from without completely disabling the plugin, ValidatingAdmissionWebhooks and MutatingAdmissionWebhooks are never called on admission requests for ValidatingWebhookConfiguration and MutatingWebhookConfiguration objects.

rules[]

object

RuleWithOperations is a tuple of Operations and Resources. It is recommended to make sure that all the tuple expansions are valid.

sideEffects

string

SideEffects states whether this webhook has side effects. Acceptable values are: None, NoneOnDryRun (webhooks created via v1beta1 may also specify Some or Unknown). Webhooks with side effects MUST implement a reconciliation system, since a request may be rejected by a future step in the admission change and the side effects therefore need to be undone. Requests with the dryRun attribute will be auto-rejected if they match a webhook with sideEffects == Unknown or Some.

timeoutSeconds

integer

TimeoutSeconds specifies the timeout for this webhook. After the timeout passes, the webhook call will be ignored or the API call will fail based on the failure policy. The timeout value must be between 1 and 30 seconds. Default to 10 seconds.

.webhooks[].clientConfig
Description

WebhookClientConfig contains the information to make a TLS connection with the webhook

Type

object

Property Type Description

caBundle

string

caBundle is a PEM encoded CA bundle which will be used to validate the webhook’s server certificate. If unspecified, system trust roots on the apiserver are used.

service

object

ServiceReference holds a reference to Service.legacy.k8s.io

url

string

url gives the location of the webhook, in standard URL form (scheme://host:port/path). Exactly one of url or service must be specified.

The host should not refer to a service running in the cluster; use the service field instead. The host might be resolved via external DNS in some apiservers (e.g., kube-apiserver cannot resolve in-cluster DNS as that would be a layering violation). host may also be an IP address.

Please note that using localhost or 127.0.0.1 as a host is risky unless you take great care to run this webhook on all hosts which run an apiserver which might need to make calls to this webhook. Such installs are likely to be non-portable, i.e., not easy to turn up in a new cluster.

The scheme must be "https"; the URL must begin with "https://".

A path is optional, and if present may be any string permissible in a URL. You may use the path to pass an arbitrary string to the webhook, for example, a cluster identifier.

Attempting to use a user or basic auth e.g. "user:password@" is not allowed. Fragments ("#…​") and query parameters ("?…​") are not allowed, either.

.webhooks[].clientConfig.service
Description

ServiceReference holds a reference to Service.legacy.k8s.io

Type

object

Required
  • namespace

  • name

Property Type Description

name

string

name is the name of the service. Required

namespace

string

namespace is the namespace of the service. Required

path

string

path is an optional URL path which will be sent in any request to this service.

port

integer

If specified, the port on the service that hosting webhook. Default to 443 for backward compatibility. port should be a valid port number (1-65535, inclusive).

.webhooks[].rules
Description

Rules describes what operations on what resources/subresources the webhook cares about. The webhook cares about an operation if it matches any Rule. However, in order to prevent ValidatingAdmissionWebhooks and MutatingAdmissionWebhooks from putting the cluster in a state which cannot be recovered from without completely disabling the plugin, ValidatingAdmissionWebhooks and MutatingAdmissionWebhooks are never called on admission requests for ValidatingWebhookConfiguration and MutatingWebhookConfiguration objects.

Type

array

.webhooks[].rules[]
Description

RuleWithOperations is a tuple of Operations and Resources. It is recommended to make sure that all the tuple expansions are valid.

Type

object

Property Type Description

apiGroups

array (string)

APIGroups is the API groups the resources belong to. '' is all groups. If '' is present, the length of the slice must be one. Required.

apiVersions

array (string)

APIVersions is the API versions the resources belong to. '' is all versions. If '' is present, the length of the slice must be one. Required.

operations

array (string)

Operations is the operations the admission hook cares about - CREATE, UPDATE, or * for all operations. If '*' is present, the length of the slice must be one. Required.

resources

array (string)

Resources is a list of resources this rule applies to.

For example: 'pods' means pods. 'pods/log' means the log subresource of pods. '' means all resources, but not subresources. 'pods/' means all subresources of pods. '/scale' means all scale subresources. '/*' means all resources and their subresources.

If wildcard is present, the validation rule will ensure resources do not overlap with each other.

Depending on the enclosing object, subresources might not be allowed. Required.

scope

string

scope specifies the scope of this rule. Valid values are "Cluster", "Namespaced", and "" "Cluster" means that only cluster-scoped resources will match this rule. Namespace API objects are cluster-scoped. "Namespaced" means that only namespaced resources will match this rule. "" means that there are no scope restrictions. Subresources match the scope of their parent resource. Default is "*".

API endpoints

The following API endpoints are available:

  • /apis/admissionregistration.k8s.io/v1/validatingwebhookconfigurations

    • DELETE: delete collection of ValidatingWebhookConfiguration

    • GET: list or watch objects of kind ValidatingWebhookConfiguration

    • POST: create a ValidatingWebhookConfiguration

  • /apis/admissionregistration.k8s.io/v1/validatingwebhookconfigurations/{name}

    • DELETE: delete a ValidatingWebhookConfiguration

    • GET: read the specified ValidatingWebhookConfiguration

    • PATCH: partially update the specified ValidatingWebhookConfiguration

    • PUT: replace the specified ValidatingWebhookConfiguration

/apis/admissionregistration.k8s.io/v1/validatingwebhookconfigurations

Table 1. Global guery parameters
Parameter Type Description

pretty

string

If 'true', then the output is pretty printed.

HTTP method

DELETE

Description

delete collection of ValidatingWebhookConfiguration

Table 2. Query parameters
Parameter Type Description

allowWatchBookmarks

boolean

allowWatchBookmarks requests watch events with type "BOOKMARK". Servers that do not implement bookmarks may ignore this flag and bookmarks are sent at the server's discretion. Clients should not assume bookmarks are returned at any specific interval, nor may they assume the server will send any BOOKMARK event during a session. If this is not a watch, this field is ignored. If the feature gate WatchBookmarks is not enabled in apiserver, this field is ignored.

continue

string

The continue option should be set when retrieving more results from the server. Since this value is server defined, clients may only use the continue value from a previous query result with identical query parameters (except for the value of continue) and the server may reject a continue value it does not recognize. If the specified continue value is no longer valid whether due to expiration (generally five to fifteen minutes) or a configuration change on the server, the server will respond with a 410 ResourceExpired error together with a continue token. If the client needs a consistent list, it must restart their list without the continue field. Otherwise, the client may send another list request with the token received with the 410 error, the server will respond with a list starting from the next key, but from the latest snapshot, which is inconsistent from the previous list results - objects that are created, modified, or deleted after the first list request will be included in the response, as long as their keys are after the "next key".

This field is not supported when watch is true. Clients may start a watch from the last resourceVersion value returned by the server and not miss any modifications.

dryRun

string

When present, indicates that modifications should not be persisted. An invalid or unrecognized dryRun directive will result in an error response and no further processing of the request. Valid values are: - All: all dry run stages will be processed

fieldSelector

string

A selector to restrict the list of returned objects by their fields. Defaults to everything.

gracePeriodSeconds

integer

The duration in seconds before the object should be deleted. Value must be non-negative integer. The value zero indicates delete immediately. If this value is nil, the default grace period for the specified type will be used. Defaults to a per object value if not specified. zero means delete immediately.

labelSelector

string

A selector to restrict the list of returned objects by their labels. Defaults to everything.

limit

integer

limit is a maximum number of responses to return for a list call. If more items exist, the server will set the `continue` field on the list metadata to a value that can be used with the same initial query to retrieve the next set of results. Setting a limit may return fewer than the requested amount of items (up to zero items) in the event all requested objects are filtered out and clients should only use the presence of the continue field to determine whether more results are available. Servers may choose not to support the limit argument and will return all of the available results. If limit is specified and the continue field is empty, clients may assume that no more results are available. This field is not supported if watch is true.

The server guarantees that the objects returned when using continue will be identical to issuing a single list call without a limit - that is, no objects created, modified, or deleted after the first request is issued will be included in any subsequent continued requests. This is sometimes referred to as a consistent snapshot, and ensures that a client that is using limit to receive smaller chunks of a very large result can ensure they see all possible objects. If objects are updated during a chunked list the version of the object that was present at the time the first list result was calculated is returned.

orphanDependents

boolean

Deprecated: please use the PropagationPolicy, this field will be deprecated in 1.7. Should the dependent objects be orphaned. If true/false, the "orphan" finalizer will be added to/removed from the object's finalizers list. Either this field or PropagationPolicy may be set, but not both.

propagationPolicy

string

Whether and how garbage collection will be performed. Either this field or OrphanDependents may be set, but not both. The default policy is decided by the existing finalizer set in the metadata.finalizers and the resource-specific default policy. Acceptable values are: 'Orphan' - orphan the dependents; 'Background' - allow the garbage collector to delete the dependents in the background; 'Foreground' - a cascading policy that deletes all dependents in the foreground.

resourceVersion

string

When specified with a watch call, shows changes that occur after that particular version of a resource. Defaults to changes from the beginning of history. When specified for list: - if unset, then the result is returned from remote storage based on quorum-read flag; - if it's 0, then we simply return what we currently have in cache, no guarantee; - if set to non zero, then the result is at least as fresh as given rv.

timeoutSeconds

integer

Timeout for the list/watch call. This limits the duration of the call, regardless of any activity or inactivity.

watch

boolean

Watch for changes to the described resources and return them as a stream of add, update, and remove notifications. Specify resourceVersion.

Table 3. Body parameters
Parameter Type Description

body

DeleteOptions meta/v1

Table 4. HTTP responses
HTTP code Reponse body

200 - OK

Status meta/v1

401 - Unauthorized

Empty

HTTP method

GET

Description

list or watch objects of kind ValidatingWebhookConfiguration

Table 5. Query parameters
Parameter Type Description

allowWatchBookmarks

boolean

allowWatchBookmarks requests watch events with type "BOOKMARK". Servers that do not implement bookmarks may ignore this flag and bookmarks are sent at the server's discretion. Clients should not assume bookmarks are returned at any specific interval, nor may they assume the server will send any BOOKMARK event during a session. If this is not a watch, this field is ignored. If the feature gate WatchBookmarks is not enabled in apiserver, this field is ignored.

continue

string

The continue option should be set when retrieving more results from the server. Since this value is server defined, clients may only use the continue value from a previous query result with identical query parameters (except for the value of continue) and the server may reject a continue value it does not recognize. If the specified continue value is no longer valid whether due to expiration (generally five to fifteen minutes) or a configuration change on the server, the server will respond with a 410 ResourceExpired error together with a continue token. If the client needs a consistent list, it must restart their list without the continue field. Otherwise, the client may send another list request with the token received with the 410 error, the server will respond with a list starting from the next key, but from the latest snapshot, which is inconsistent from the previous list results - objects that are created, modified, or deleted after the first list request will be included in the response, as long as their keys are after the "next key".

This field is not supported when watch is true. Clients may start a watch from the last resourceVersion value returned by the server and not miss any modifications.

fieldSelector

string

A selector to restrict the list of returned objects by their fields. Defaults to everything.

labelSelector

string

A selector to restrict the list of returned objects by their labels. Defaults to everything.

limit

integer

limit is a maximum number of responses to return for a list call. If more items exist, the server will set the `continue` field on the list metadata to a value that can be used with the same initial query to retrieve the next set of results. Setting a limit may return fewer than the requested amount of items (up to zero items) in the event all requested objects are filtered out and clients should only use the presence of the continue field to determine whether more results are available. Servers may choose not to support the limit argument and will return all of the available results. If limit is specified and the continue field is empty, clients may assume that no more results are available. This field is not supported if watch is true.

The server guarantees that the objects returned when using continue will be identical to issuing a single list call without a limit - that is, no objects created, modified, or deleted after the first request is issued will be included in any subsequent continued requests. This is sometimes referred to as a consistent snapshot, and ensures that a client that is using limit to receive smaller chunks of a very large result can ensure they see all possible objects. If objects are updated during a chunked list the version of the object that was present at the time the first list result was calculated is returned.

resourceVersion

string

When specified with a watch call, shows changes that occur after that particular version of a resource. Defaults to changes from the beginning of history. When specified for list: - if unset, then the result is returned from remote storage based on quorum-read flag; - if it's 0, then we simply return what we currently have in cache, no guarantee; - if set to non zero, then the result is at least as fresh as given rv.

timeoutSeconds

integer

Timeout for the list/watch call. This limits the duration of the call, regardless of any activity or inactivity.

watch

boolean

Watch for changes to the described resources and return them as a stream of add, update, and remove notifications. Specify resourceVersion.

Table 6. HTTP responses
HTTP code Reponse body

200 - OK

ValidatingWebhookConfigurationList admissionregistration.k8s.io/v1

401 - Unauthorized

Empty

HTTP method

POST

Description

create a ValidatingWebhookConfiguration

Table 7. Query parameters
Parameter Type Description

dryRun

string

When present, indicates that modifications should not be persisted. An invalid or unrecognized dryRun directive will result in an error response and no further processing of the request. Valid values are: - All: all dry run stages will be processed

fieldManager

string

fieldManager is a name associated with the actor or entity that is making these changes. The value must be less than or 128 characters long, and only contain printable characters, as defined by https://golang.org/pkg/unicode/#IsPrint.

Table 8. Body parameters
Parameter Type Description

body

ValidatingWebhookConfiguration admissionregistration.k8s.io/v1

Table 9. HTTP responses
HTTP code Reponse body

200 - OK

ValidatingWebhookConfiguration admissionregistration.k8s.io/v1

201 - Created

ValidatingWebhookConfiguration admissionregistration.k8s.io/v1

202 - Accepted

ValidatingWebhookConfiguration admissionregistration.k8s.io/v1

401 - Unauthorized

Empty

/apis/admissionregistration.k8s.io/v1/validatingwebhookconfigurations/{name}

Table 10. Global path parameters
Parameter Type Description

name

string

name of the ValidatingWebhookConfiguration

Table 11. Global guery parameters
Parameter Type Description

pretty

string

If 'true', then the output is pretty printed.

HTTP method

DELETE

Description

delete a ValidatingWebhookConfiguration

Table 12. Query parameters
Parameter Type Description

dryRun

string

When present, indicates that modifications should not be persisted. An invalid or unrecognized dryRun directive will result in an error response and no further processing of the request. Valid values are: - All: all dry run stages will be processed

gracePeriodSeconds

integer

The duration in seconds before the object should be deleted. Value must be non-negative integer. The value zero indicates delete immediately. If this value is nil, the default grace period for the specified type will be used. Defaults to a per object value if not specified. zero means delete immediately.

orphanDependents

boolean

Deprecated: please use the PropagationPolicy, this field will be deprecated in 1.7. Should the dependent objects be orphaned. If true/false, the "orphan" finalizer will be added to/removed from the object's finalizers list. Either this field or PropagationPolicy may be set, but not both.

propagationPolicy

string

Whether and how garbage collection will be performed. Either this field or OrphanDependents may be set, but not both. The default policy is decided by the existing finalizer set in the metadata.finalizers and the resource-specific default policy. Acceptable values are: 'Orphan' - orphan the dependents; 'Background' - allow the garbage collector to delete the dependents in the background; 'Foreground' - a cascading policy that deletes all dependents in the foreground.

Table 13. Body parameters
Parameter Type Description

body

DeleteOptions meta/v1

Table 14. HTTP responses
HTTP code Reponse body

200 - OK

Status meta/v1

202 - Accepted

Status meta/v1

401 - Unauthorized

Empty

HTTP method

GET

Description

read the specified ValidatingWebhookConfiguration

Table 15. Query parameters
Parameter Type Description

exact

boolean

Should the export be exact. Exact export maintains cluster-specific fields like 'Namespace'. Deprecated. Planned for removal in 1.18.

export

boolean

Should this value be exported. Export strips fields that a user can not specify. Deprecated. Planned for removal in 1.18.

Table 16. HTTP responses
HTTP code Reponse body

200 - OK

ValidatingWebhookConfiguration admissionregistration.k8s.io/v1

401 - Unauthorized

Empty

HTTP method

PATCH

Description

partially update the specified ValidatingWebhookConfiguration

Table 17. Query parameters
Parameter Type Description

dryRun

string

When present, indicates that modifications should not be persisted. An invalid or unrecognized dryRun directive will result in an error response and no further processing of the request. Valid values are: - All: all dry run stages will be processed

fieldManager

string

fieldManager is a name associated with the actor or entity that is making these changes. The value must be less than or 128 characters long, and only contain printable characters, as defined by https://golang.org/pkg/unicode/#IsPrint. This field is required for apply requests (application/apply-patch) but optional for non-apply patch types (JsonPatch, MergePatch, StrategicMergePatch).

force

boolean

Force is going to "force" Apply requests. It means user will re-acquire conflicting fields owned by other people. Force flag must be unset for non-apply patch requests.

Table 18. Body parameters
Parameter Type Description

body

Patch meta/v1

Table 19. HTTP responses
HTTP code Reponse body

200 - OK

ValidatingWebhookConfiguration admissionregistration.k8s.io/v1

401 - Unauthorized

Empty

HTTP method

PUT

Description

replace the specified ValidatingWebhookConfiguration

Table 20. Query parameters
Parameter Type Description

dryRun

string

When present, indicates that modifications should not be persisted. An invalid or unrecognized dryRun directive will result in an error response and no further processing of the request. Valid values are: - All: all dry run stages will be processed

fieldManager

string

fieldManager is a name associated with the actor or entity that is making these changes. The value must be less than or 128 characters long, and only contain printable characters, as defined by https://golang.org/pkg/unicode/#IsPrint.

Table 21. Body parameters
Parameter Type Description

body

ValidatingWebhookConfiguration admissionregistration.k8s.io/v1

Table 22. HTTP responses
HTTP code Reponse body

200 - OK

ValidatingWebhookConfiguration admissionregistration.k8s.io/v1

201 - Created

ValidatingWebhookConfiguration admissionregistration.k8s.io/v1

401 - Unauthorized

Empty