v1alpha1

type AuditAnnotation struct {
	// 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.
	Key string `json:"key" protobuf:"bytes,1,opt,name=key"`

	// 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.
	ValueExpression string `json:"valueExpression" protobuf:"bytes,2,opt,name=valueExpression"`
}

type ExpressionWarning struct {
	// The path to the field that refers the expression.
	// For example, the reference to the expression of the first item of
	// validations is "spec.validations[0].expression"
	FieldRef string `json:"fieldRef" protobuf:"bytes,2,opt,name=fieldRef"`
	// 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.
	Warning string `json:"warning" protobuf:"bytes,3,opt,name=warning"`
}

type FailurePolicyType string

type MatchCondition v1.MatchCondition

type MatchPolicyType string

type MatchResources struct {
	// 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.
	// +optional
	NamespaceSelector *metav1.LabelSelector `json:"namespaceSelector,omitempty" protobuf:"bytes,1,opt,name=namespaceSelector"`
	// 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.
	// +optional
	ObjectSelector *metav1.LabelSelector `json:"objectSelector,omitempty" protobuf:"bytes,2,opt,name=objectSelector"`
	// ResourceRules describes what operations on what resources/subresources the ValidatingAdmissionPolicy matches.
	// The policy cares about an operation if it matches _any_ Rule.
	// +listType=atomic
	// +optional
	ResourceRules []NamedRuleWithOperations `json:"resourceRules,omitempty" protobuf:"bytes,3,rep,name=resourceRules"`
	// 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)
	// +listType=atomic
	// +optional
	ExcludeResourceRules []NamedRuleWithOperations `json:"excludeResourceRules,omitempty" protobuf:"bytes,4,rep,name=excludeResourceRules"`
	// 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"
	// +optional
	MatchPolicy *MatchPolicyType `json:"matchPolicy,omitempty" protobuf:"bytes,7,opt,name=matchPolicy,casttype=MatchPolicyType"`
}

type NamedRuleWithOperations struct {
	// ResourceNames is an optional white list of names that the rule applies to.  An empty set means that everything is allowed.
	// +listType=atomic
	// +optional
	ResourceNames []string `json:"resourceNames,omitempty" protobuf:"bytes,1,rep,name=resourceNames"`
	// RuleWithOperations is a tuple of Operations and Resources.
	RuleWithOperations `json:",inline" protobuf:"bytes,2,opt,name=ruleWithOperations"`
}

type OperationType = v1.OperationType

type ParamKind struct {
	// APIVersion is the API group version the resources belong to.
	// In format of "group/version".
	// Required.
	APIVersion string `json:"apiVersion,omitempty" protobuf:"bytes,1,rep,name=apiVersion"`

	// Kind is the API kind the resources belong to.
	// Required.
	Kind string `json:"kind,omitempty" protobuf:"bytes,2,rep,name=kind"`
}

type ParamRef struct {
	// `name` is the name of the resource being referenced.
	//
	// `name` and `selector` are mutually exclusive properties. If one is set,
	// the other must be unset.
	//
	// +optional
	Name string `json:"name,omitempty" protobuf:"bytes,1,rep,name=name"`

	// namespace is the namespace of the referenced resource. Allows limiting
	// the search for params to a specific namespace. Applies to both `name` and
	// `selector` fields.
	//
	// A per-namespace parameter may be used by specifying a namespace-scoped
	// `paramKind` in the policy and leaving this field empty.
	//
	// - If `paramKind` is cluster-scoped, this field MUST be unset. Setting this
	// field results in a configuration error.
	//
	// - If `paramKind` is namespace-scoped, the namespace of the object being
	// evaluated for admission will be used when this field is left unset. Take
	// care that if this is left empty the binding must not match any cluster-scoped
	// resources, which will result in an error.
	//
	// +optional
	Namespace string `json:"namespace,omitempty" protobuf:"bytes,2,rep,name=namespace"`

	// selector can be used to match multiple param objects based on their labels.
	// Supply selector: {} to match all resources of the ParamKind.
	//
	// If multiple params are found, they are all evaluated with the policy expressions
	// and the results are ANDed together.
	//
	// One of `name` or `selector` must be set, but `name` and `selector` are
	// mutually exclusive properties. If one is set, the other must be unset.
	//
	// +optional
	Selector *metav1.LabelSelector `json:"selector,omitempty" protobuf:"bytes,3,rep,name=selector"`

	// `parameterNotFoundAction` controls the behavior of the binding when the resource
	// exists, and name or selector is valid, but there are no parameters
	// matched by the binding. If the value is set to `Allow`, then no
	// matched parameters will be treated as successful validation by the binding.
	// If set to `Deny`, then no matched parameters will be subject to the
	// `failurePolicy` of the policy.
	//
	// Allowed values are `Allow` or `Deny`
	// Default to `Deny`
	// +optional
	ParameterNotFoundAction *ParameterNotFoundActionType `json:"parameterNotFoundAction,omitempty" protobuf:"bytes,4,rep,name=parameterNotFoundAction"`
}

type ParameterNotFoundActionType string

type Rule = v1.Rule

type RuleWithOperations = v1.RuleWithOperations

type ScopeType = v1.ScopeType

type TypeChecking struct {
	// The type checking warnings for each expression.
	// +optional
	// +listType=atomic
	ExpressionWarnings []ExpressionWarning `json:"expressionWarnings,omitempty" protobuf:"bytes,1,rep,name=expressionWarnings"`
}

type ValidatingAdmissionPolicy struct {
	metav1.TypeMeta `json:",inline"`
	// Standard object metadata; More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#metadata.
	// +optional
	metav1.ObjectMeta `json:"metadata,omitempty" protobuf:"bytes,1,opt,name=metadata"`
	// Specification of the desired behavior of the ValidatingAdmissionPolicy.
	Spec ValidatingAdmissionPolicySpec `json:"spec,omitempty" protobuf:"bytes,2,opt,name=spec"`
	// The 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.
	// +optional
	Status ValidatingAdmissionPolicyStatus `json:"status,omitempty" protobuf:"bytes,3,opt,name=status"`
}

type ValidatingAdmissionPolicyBinding struct {
	metav1.TypeMeta `json:",inline"`
	// Standard object metadata; More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#metadata.
	// +optional
	metav1.ObjectMeta `json:"metadata,omitempty" protobuf:"bytes,1,opt,name=metadata"`
	// Specification of the desired behavior of the ValidatingAdmissionPolicyBinding.
	Spec ValidatingAdmissionPolicyBindingSpec `json:"spec,omitempty" protobuf:"bytes,2,opt,name=spec"`
}

type ValidatingAdmissionPolicyBindingList struct {
	metav1.TypeMeta `json:",inline"`
	// Standard list metadata.
	// More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#types-kinds
	// +optional
	metav1.ListMeta `json:"metadata,omitempty" protobuf:"bytes,1,opt,name=metadata"`
	// List of PolicyBinding.
	Items []ValidatingAdmissionPolicyBinding `json:"items,omitempty" protobuf:"bytes,2,rep,name=items"`
}

type ValidatingAdmissionPolicyBindingSpec struct {
	// PolicyName references a ValidatingAdmissionPolicy name which the ValidatingAdmissionPolicyBinding binds to.
	// If the referenced resource does not exist, this binding is considered invalid and will be ignored
	// Required.
	PolicyName string `json:"policyName,omitempty" protobuf:"bytes,1,rep,name=policyName"`

	// paramRef specifies the parameter resource used to configure the admission control policy.
	// It should point to a resource of the type specified in ParamKind of the bound ValidatingAdmissionPolicy.
	// If the policy specifies a ParamKind and the resource referred to by ParamRef does not exist, this binding is considered mis-configured and the FailurePolicy of the ValidatingAdmissionPolicy applied.
	// If the policy does not specify a ParamKind then this field is ignored, and the rules are evaluated without a param.
	// +optional
	ParamRef *ParamRef `json:"paramRef,omitempty" protobuf:"bytes,2,rep,name=paramRef"`

	// MatchResources declares what resources match this binding and will be validated by it.
	// Note that this is intersected with the policy's matchConstraints, so only requests that are matched by the policy can be selected by this.
	// If this is unset, all resources matched by the policy are validated by this binding
	// When resourceRules is unset, it does not constrain resource matching. If a resource is matched by the other fields of this object, it will be validated.
	// Note that this is differs from ValidatingAdmissionPolicy matchConstraints, where resourceRules are required.
	// +optional
	MatchResources *MatchResources `json:"matchResources,omitempty" protobuf:"bytes,3,rep,name=matchResources"`

	// validationActions declares how Validations of the referenced ValidatingAdmissionPolicy are enforced.
	// If a validation evaluates to false it is always enforced according to these actions.
	//
	// Failures defined by the ValidatingAdmissionPolicy's FailurePolicy are enforced according
	// to these actions only if the FailurePolicy is set to Fail, otherwise the failures are
	// ignored. This includes compilation errors, runtime errors and misconfigurations of the policy.
	//
	// validationActions is declared as a set of action values. Order does
	// not matter. validationActions may not contain duplicates of the same action.
	//
	// The supported actions values are:
	//
	// "Deny" specifies that a validation failure results in a denied request.
	//
	// "Warn" specifies that a validation failure is reported to the request client
	// in HTTP Warning headers, with a warning code of 299. Warnings can be sent
	// both for allowed or denied admission responses.
	//
	// "Audit" specifies that a validation failure is included in the published
	// audit event for the request. The audit event will contain a
	// `validation.policy.admission.k8s.io/validation_failure` audit annotation
	// with a value containing the details of the validation failures, formatted as
	// a JSON list of objects, each with the following fields:
	// - message: The validation failure message string
	// - policy: The resource name of the ValidatingAdmissionPolicy
	// - binding: The resource name of the ValidatingAdmissionPolicyBinding
	// - expressionIndex: The index of the failed validations in the ValidatingAdmissionPolicy
	// - validationActions: The enforcement actions enacted for the validation failure
	// Example audit annotation:
	// `"validation.policy.admission.k8s.io/validation_failure": "[{\"message\": \"Invalid value\", {\"policy\": \"policy.example.com\", {\"binding\": \"policybinding.example.com\", {\"expressionIndex\": \"1\", {\"validationActions\": [\"Audit\"]}]"`
	//
	// Clients should expect to handle additional values by ignoring
	// any values not recognized.
	//
	// "Deny" and "Warn" may not be used together since this combination
	// needlessly duplicates the validation failure both in the
	// API response body and the HTTP warning headers.
	//
	// Required.
	// +listType=set
	ValidationActions []ValidationAction `json:"validationActions,omitempty" protobuf:"bytes,4,rep,name=validationActions"`
}

type ValidatingAdmissionPolicyList struct {
	metav1.TypeMeta `json:",inline"`
	// Standard list metadata.
	// More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#types-kinds
	// +optional
	metav1.ListMeta `json:"metadata,omitempty" protobuf:"bytes,1,opt,name=metadata"`
	// List of ValidatingAdmissionPolicy.
	Items []ValidatingAdmissionPolicy `json:"items,omitempty" protobuf:"bytes,2,rep,name=items"`
}

type ValidatingAdmissionPolicySpec struct {
	// 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.
	// +optional
	ParamKind *ParamKind `json:"paramKind,omitempty" protobuf:"bytes,1,rep,name=paramKind"`

	// 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.
	MatchConstraints *MatchResources `json:"matchConstraints,omitempty" protobuf:"bytes,2,rep,name=matchConstraints"`

	// 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.
	// +listType=atomic
	// +optional
	Validations []Validation `json:"validations,omitempty" protobuf:"bytes,3,rep,name=validations"`

	// 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.
	// +optional
	FailurePolicy *FailurePolicyType `json:"failurePolicy,omitempty" protobuf:"bytes,4,opt,name=failurePolicy,casttype=FailurePolicyType"`

	// 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.
	// +listType=atomic
	// +optional
	AuditAnnotations []AuditAnnotation `json:"auditAnnotations,omitempty" protobuf:"bytes,5,rep,name=auditAnnotations"`

	// 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
	//
	// +patchMergeKey=name
	// +patchStrategy=merge
	// +listType=map
	// +listMapKey=name
	// +optional
	MatchConditions []MatchCondition `json:"matchConditions,omitempty" patchStrategy:"merge" patchMergeKey:"name" protobuf:"bytes,6,rep,name=matchConditions"`

	// 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.
	// +patchMergeKey=name
	// +patchStrategy=merge
	// +listType=map
	// +listMapKey=name
	// +optional
	Variables []Variable `json:"variables,omitempty" patchStrategy:"merge" patchMergeKey:"name" protobuf:"bytes,7,rep,name=variables"`
}

type ValidatingAdmissionPolicyStatus struct {
	// The generation observed by the controller.
	// +optional
	ObservedGeneration int64 `json:"observedGeneration,omitempty" protobuf:"varint,1,opt,name=observedGeneration"`
	// The results of type checking for each expression.
	// Presence of this field indicates the completion of the type checking.
	// +optional
	TypeChecking *TypeChecking `json:"typeChecking,omitempty" protobuf:"bytes,2,opt,name=typeChecking"`
	// The conditions represent the latest available observations of a policy's current state.
	// +optional
	// +listType=map
	// +listMapKey=type
	Conditions []metav1.Condition `json:"conditions,omitempty" protobuf:"bytes,3,rep,name=conditions"`
}

type Validation struct {
	// 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.
	Expression string `json:"expression" protobuf:"bytes,1,opt,name=Expression"`
	// 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}".
	// +optional
	Message string `json:"message,omitempty" protobuf:"bytes,2,opt,name=message"`
	// 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.
	// +optional
	Reason *metav1.StatusReason `json:"reason,omitempty" protobuf:"bytes,3,opt,name=reason"`
	// 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)+")"
	// +optional
	MessageExpression string `json:"messageExpression,omitempty" protobuf:"bytes,4,opt,name=messageExpression"`
}

type ValidationAction string

type Variable struct {
	// Name is the name of the variable. The name must be a valid CEL identifier and unique among all variables.
	// The variable can be accessed in other expressions through `variables`
	// For example, if name is "foo", the variable will be available as `variables.foo`
	Name string `json:"name" protobuf:"bytes,1,opt,name=Name"`

	// Expression is the expression that will be evaluated as the value of the variable.
	// The CEL expression has access to the same identifiers as the CEL expressions in Validation.
	Expression string `json:"expression" protobuf:"bytes,2,opt,name=Expression"`
}