ValidatingAdmissionPolicy

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

apiVersion: admissionregistration.k8s.io/v1

import "k8s.io/api/admissionregistration/v1"

ValidatingAdmissionPolicy

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

Field	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	metadata is the standard object metadata; More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#metadata.
`spec` ValidatingAdmissionPolicySpec	spec defines the desired behavior of the ValidatingAdmissionPolicy.
`status` ValidatingAdmissionPolicyStatus	status represents the current status of the ValidatingAdmissionPolicy, including warnings that are useful to determine if the policy behaves in the expected way. Populated by the system. Read-only.

ValidatingAdmissionPolicySpec

ValidatingAdmissionPolicySpec is the specification of the desired behavior of the AdmissionPolicy.

Field	Description
`auditAnnotations` AuditAnnotation array	auditAnnotations contains CEL expressions which are used to produce audit annotations for the audit event of the API request. validations and auditAnnotations may not both be empty; a least one of validations or auditAnnotations is required.
`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 spec.paramKind refers to a non-existent Kind. A binding is invalid if spec.paramRef.name refers to a non-existent resource. failurePolicy does not define how validations that evaluate to false are handled. When failurePolicy is set to Fail, ValidatingAdmissionPolicyBinding validationActions define how failures are enforced. Allowed values are Ignore or Fail. Defaults to Fail. Possible enum values: - `"Fail"` means that an error calling the webhook causes the admission to fail. - `"Ignore"` means that an error calling the webhook is ignored.
`matchConditions` MatchCondition array patch strategy: merge on key `name`	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 rules, namespaceSelector, and objectSelector. 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
`matchConstraints` MatchResources	matchConstraints specifies what resources this policy is designed to validate. The AdmissionPolicy 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 ValidatingAdmissionPolicy cannot match ValidatingAdmissionPolicy and ValidatingAdmissionPolicyBinding. Required.
`paramKind` ParamKind	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 ValidatingAdmissionPolicyBinding, the params variable will be null.
`validations` Validation array	validations contain CEL expressions which is used to apply the validation. Validations and AuditAnnotations may not both be empty; a minimum of one Validations or AuditAnnotations is required.
`variables` Variable array patch strategy: merge on key `name`	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.

ValidatingAdmissionPolicyStatus

ValidatingAdmissionPolicyStatus represents the status of an admission validation policy.

Field	Description
`conditions` Condition array	conditions represent the latest available observations of a policy's current state.
`observedGeneration` integer	observedGeneration is the generation observed by the controller.
`typeChecking` TypeChecking	typeChecking contains the results of type checking for each expression. Presence of this field indicates the completion of the type checking.

ValidatingAdmissionPolicyList

ValidatingAdmissionPolicyList is a list of ValidatingAdmissionPolicy.

Field	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
`items` * ValidatingAdmissionPolicy array	List of ValidatingAdmissionPolicy.
`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` ListMeta	metadata is the standard list metadata. More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#types-kinds

AuditAnnotation

AuditAnnotation describes how to produce an audit annotation for an API request.

Field Description

key *
string key specifies the audit annotation key. The audit annotation keys of a ValidatingAdmissionPolicy must be unique. The key must be a qualified name ([A-Za-z0-9][-A-Za-z0-9_.]*) no more than 63 bytes in length. The key is combined with the resource name of the ValidatingAdmissionPolicy to construct an audit annotation key: "{ValidatingAdmissionPolicy name}/{key}". If an admission webhook uses the same resource name as this ValidatingAdmissionPolicy and the same audit annotation key, the annotation key will be identical. In this case, the first annotation written with the key will be included in the audit event and all subsequent annotations with the same key will be discarded. Required.

valueExpression *
string valueExpression represents the expression which is evaluated by CEL to produce an audit annotation value. The expression must evaluate to either a string or null value. If the expression evaluates to a string, the audit annotation is included with the string value. If the expression evaluates to null or empty string the audit annotation will be omitted. The valueExpression may be no longer than 5kb in length. If the result of the valueExpression is more than 10kb in length, it will be truncated to 10kb. If multiple ValidatingAdmissionPolicyBinding resources match an API request, then the valueExpression will be evaluated for each binding. All unique values produced by the valueExpressions will be joined together in a comma-separated list. Required.

Field	Description
`key` * string	key specifies the audit annotation key. The audit annotation keys of a ValidatingAdmissionPolicy must be unique. The key must be a qualified name ([A-Za-z0-9][-A-Za-z0-9_.]*) no more than 63 bytes in length. The key is combined with the resource name of the ValidatingAdmissionPolicy to construct an audit annotation key: "{ValidatingAdmissionPolicy name}/{key}". If an admission webhook uses the same resource name as this ValidatingAdmissionPolicy and the same audit annotation key, the annotation key will be identical. In this case, the first annotation written with the key will be included in the audit event and all subsequent annotations with the same key will be discarded. Required.
`valueExpression` * string	valueExpression represents the expression which is evaluated by CEL to produce an audit annotation value. The expression must evaluate to either a string or null value. If the expression evaluates to a string, the audit annotation is included with the string value. If the expression evaluates to null or empty string the audit annotation will be omitted. The valueExpression may be no longer than 5kb in length. If the result of the valueExpression is more than 10kb in length, it will be truncated to 10kb. If multiple ValidatingAdmissionPolicyBinding resources match an API request, then the valueExpression will be evaluated for each binding. All unique values produced by the valueExpressions will be joined together in a comma-separated list. Required.

ExpressionWarning

ExpressionWarning is a warning information that targets a specific expression.

Field	Description
`fieldRef` * string	fieldRef is the path to the field that refers to the expression. For example, the reference to the expression of the first item of validations is "spec.validations[0].expression"
`warning` * string	warning contains the content of type checking information in a human-readable form. Each line of the warning contains the type that the expression is checked against, followed by the type check error from the compiler.

TypeChecking

TypeChecking contains results of type checking the expressions in the ValidatingAdmissionPolicy

Field	Description
`expressionWarnings` ExpressionWarning array	expressionWarnings contains the type checking warnings for each expression.

Validation

Validation specifies the CEL expression which is used to apply the validation.

Field	Description
`expression` * string	expression represents the expression which will be evaluated by CEL. ref: https://github.com/google/cel-spec CEL expressions have access to the contents of the API request/response, organized into CEL variables as well as some other useful variables: - 'object' - The object from the incoming request. The value is null for DELETE requests. - 'oldObject' - The existing object. The value is null for CREATE requests. - 'request' - Attributes of the API request([ref](/pkg/apis/admission/types.go#AdmissionRequest)). - 'params' - Parameter resource referred to by the policy binding being evaluated. Only populated if the policy has a ParamKind. - 'namespaceObject' - The namespace object that the incoming object belongs to. The value is null for cluster-scoped resources. - 'variables' - Map of composited variables, from its name to its lazily evaluated value. For example, a variable named 'foo' can be accessed as 'variables.foo'. - 'authorizer' - A CEL Authorizer. May be used to perform authorization checks for the principal (user or service account) of the request. See https://pkg.go.dev/k8s.io/apiserver/pkg/cel/library#Authz - 'authorizer.requestResource' - A CEL ResourceCheck constructed from the 'authorizer' and configured with the request resource. The `apiVersion`, `kind`, `metadata.name` and `metadata.generateName` are always accessible from the root of the object. No other metadata properties are accessible. Only property names of the form `[a-zA-Z_.-/][a-zA-Z0-9_.-/]*` are accessible. Accessible property names are escaped according to the following rules when accessed in the expression: - '__' escapes to '__underscores__' - '.' escapes to '__dot__' - '-' escapes to '__dash__' - '/' escapes to '__slash__' - Property names that exactly match a CEL RESERVED keyword escape to '__{keyword}__'. The keywords are: "true", "false", "null", "in", "as", "break", "const", "continue", "else", "for", "function", "if", "import", "let", "loop", "package", "namespace", "return". Examples: - Expression accessing a property named "namespace": {"Expression": "object.__namespace__ > 0"} - Expression accessing a property named "x-prop": {"Expression": "object.x__dash__prop > 0"} - Expression accessing a property named "redact__d": {"Expression": "object.redact__underscores__d > 0"} Equality on arrays with list type of 'set' or 'map' ignores element order, i.e. [1, 2] == [2, 1]. Concatenation on arrays with x-kubernetes-list-type use the semantics of the list type: - 'set': `X + Y` performs a union where the array positions of all elements in `X` are preserved and non-intersecting elements in `Y` are appended, retaining their partial order. - 'map': `X + Y` performs a merge where the array positions of all keys in `X` are preserved but the values are overwritten by values in `Y` when the key sets of `X` and `Y` intersect. Elements in `Y` with non-intersecting keys are appended, retaining their partial order. Required.
`message` string	message represents the message displayed when validation fails. The message is required if the Expression contains line breaks. The message must not contain line breaks. If unset, the message is "failed rule: {Rule}". e.g. "must be a URL with the host matching spec.host" If the Expression contains line breaks. Message is required. The message must not contain line breaks. If unset, the message is "failed Expression: {Expression}".
`messageExpression` string	messageExpression declares a CEL expression that evaluates to the validation failure message that is returned when this rule fails. Since messageExpression is used as a failure message, it must evaluate to a string. If both message and messageExpression are present on a validation, then messageExpression will be used if validation fails. If messageExpression results in a runtime error, the runtime error is logged, and the validation failure message is produced as if the messageExpression field were unset. If messageExpression evaluates to an empty string, a string with only spaces, or a string that contains line breaks, then the validation failure message will also be produced as if the messageExpression field were unset, and the fact that messageExpression produced an empty string/string with only spaces/string with line breaks will be logged. messageExpression has access to all the same variables as the `expression` except for 'authorizer' and 'authorizer.requestResource'. Example: "object.x must be less than max ("+string(params.max)+")"
`reason` string	reason represents a machine-readable description of why this validation failed. If this is the first validation in the list to fail, this reason, as well as the corresponding HTTP response code, are used in the HTTP response to the client. The currently supported reasons are: "Unauthorized", "Forbidden", "Invalid", "RequestEntityTooLarge". If not set, StatusReasonInvalid is used in the response to the client.

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https://kubernetes.io/docs/reference/kubernetes-api/admissionregistration/validating-admission-policy-v1/