CRD Validation
These markers modify how the CRD validation schema is produced for the types and fields they modify. Each corresponds roughly to an OpenAPI/JSON schema option.
See Generating CRDs for examples.
- // +kubebuilder:default
- any
sets the default value for this field.
A default value will be accepted as any value valid for the field. Formatting for common types include: boolean:
true
, string:Cluster
, numerical:1.24
, array:{1,2}
, object:{policy: "delete"}
). Defaults should be defined in pruned form, and only best-effort validation will be performed. Full validation of a default requires submission of the containing CRD to an apiserver.- any
- // +kubebuilder:example
- any
sets the example value for this field.
An example value will be accepted as any value valid for the field. Formatting for common types include: boolean:
true
, string:Cluster
, numerical:1.24
, array:{1,2}
, object:{policy: "delete"}
). Examples should be defined in pruned form, and only best-effort validation will be performed. Full validation of an example requires submission of the containing CRD to an apiserver.- any
- // +kubebuilder:validation:EmbeddedResource
EmbeddedResource marks a fields as an embedded resource with apiVersion, kind and metadata fields.
An embedded resource is a value that has apiVersion, kind and metadata fields. They are validated implicitly according to the semantics of the currently running apiserver. It is not necessary to add any additional schema for these field, yet it is possible. This can be combined with PreserveUnknownFields.
- // +kubebuilder:validation:Enum
- any
specifies that this (scalar) field is restricted to the *exact* values specified here.
- any
- // +kubebuilder:validation:Enum
- any
specifies that this (scalar) field is restricted to the *exact* values specified here.
- any
- // +kubebuilder:validation:ExclusiveMaximum
- bool
indicates that the maximum is "up to" but not including that value.
- bool
- // +kubebuilder:validation:ExclusiveMaximum
- bool
indicates that the maximum is "up to" but not including that value.
- bool
- // +kubebuilder:validation:ExclusiveMinimum
- bool
indicates that the minimum is "up to" but not including that value.
- bool
- // +kubebuilder:validation:ExclusiveMinimum
- bool
indicates that the minimum is "up to" but not including that value.
- bool
- // +kubebuilder:validation:Format
- string
specifies additional "complex" formatting for this field.
For example, a date-time field would be marked as "type: string" and "format: date-time".
- string
- // +kubebuilder:validation:Format
- string
specifies additional "complex" formatting for this field.
For example, a date-time field would be marked as "type: string" and "format: date-time".
- string
- // +kubebuilder:validation:MaxItems
- int
specifies the maximum length for this list.
- int
- // +kubebuilder:validation:MaxItems
- int
specifies the maximum length for this list.
- int
- // +kubebuilder:validation:MaxLength
- int
specifies the maximum length for this string.
- int
- // +kubebuilder:validation:MaxLength
- int
specifies the maximum length for this string.
- int
- // +kubebuilder:validation:MaxProperties
- int
restricts the number of keys in an object
- int
- // +kubebuilder:validation:MaxProperties
- int
restricts the number of keys in an object
- int
- // +kubebuilder:validation:Maximum
specifies the maximum numeric value that this field can have.
- // +kubebuilder:validation:Maximum
specifies the maximum numeric value that this field can have.
- // +kubebuilder:validation:MinItems
- int
specifies the minimum length for this list.
- int
- // +kubebuilder:validation:MinItems
- int
specifies the minimum length for this list.
- int
- // +kubebuilder:validation:MinLength
- int
specifies the minimum length for this string.
- int
- // +kubebuilder:validation:MinLength
- int
specifies the minimum length for this string.
- int
- // +kubebuilder:validation:MinProperties
- int
restricts the number of keys in an object
- int
- // +kubebuilder:validation:MinProperties
- int
restricts the number of keys in an object
- int
- // +kubebuilder:validation:Minimum
specifies the minimum numeric value that this field can have. Negative numbers are supported.
- // +kubebuilder:validation:Minimum
specifies the minimum numeric value that this field can have. Negative numbers are supported.
- // +kubebuilder:validation:MultipleOf
specifies that this field must have a numeric value that's a multiple of this one.
- // +kubebuilder:validation:MultipleOf
specifies that this field must have a numeric value that's a multiple of this one.
- // +kubebuilder:validation:Optional
specifies that all fields in this package are optional by default.
- // +kubebuilder:validation:Optional
specifies that this field is optional, if fields are required by default.
- // +kubebuilder:validation:Pattern
- string
specifies that this string must match the given regular expression.
- string
- // +kubebuilder:validation:Pattern
- string
specifies that this string must match the given regular expression.
- string
- // +kubebuilder:validation:Required
specifies that all fields in this package are required by default.
- // +kubebuilder:validation:Required
specifies that this field is required, if fields are optional by default.
- // +kubebuilder:validation:Schemaless
marks a field as being a schemaless object.
Schemaless objects are not introspected, so you must provide any type and validation information yourself. One use for this tag is for embedding fields that hold JSONSchema typed objects. Because this field disables all type checking, it is recommended to be used only as a last resort.
- // +kubebuilder:validation:Type
- string
overrides the type for this field (which defaults to the equivalent of the Go type).
This generally must be paired with custom serialization. For example, the metav1.Time field would be marked as "type: string" and "format: date-time".
- string
- // +kubebuilder:validation:Type
- string
overrides the type for this field (which defaults to the equivalent of the Go type).
This generally must be paired with custom serialization. For example, the metav1.Time field would be marked as "type: string" and "format: date-time".
- string
- // +kubebuilder:validation:UniqueItems
- bool
specifies that all items in this list must be unique.
- bool
- // +kubebuilder:validation:UniqueItems
- bool
specifies that all items in this list must be unique.
- bool
- // +kubebuilder:validation:XEmbeddedResource
EmbeddedResource marks a fields as an embedded resource with apiVersion, kind and metadata fields.
An embedded resource is a value that has apiVersion, kind and metadata fields. They are validated implicitly according to the semantics of the currently running apiserver. It is not necessary to add any additional schema for these field, yet it is possible. This can be combined with PreserveUnknownFields.
- // +kubebuilder:validation:XEmbeddedResource
EmbeddedResource marks a fields as an embedded resource with apiVersion, kind and metadata fields.
An embedded resource is a value that has apiVersion, kind and metadata fields. They are validated implicitly according to the semantics of the currently running apiserver. It is not necessary to add any additional schema for these field, yet it is possible. This can be combined with PreserveUnknownFields.
- // +kubebuilder:validation:XIntOrString
IntOrString marks a fields as an IntOrString.
This is required when applying patterns or other validations to an IntOrString field. Knwon information about the type is applied during the collapse phase and as such is not normally available during marker application.
- // +kubebuilder:validation:XIntOrString
IntOrString marks a fields as an IntOrString.
This is required when applying patterns or other validations to an IntOrString field. Knwon information about the type is applied during the collapse phase and as such is not normally available during marker application.
- // +kubebuilder:validation:XValidation
- message
- string
- rule
- string
marks a field as requiring a value for which a given expression evaluates to true.
This marker may be repeated to specify multiple expressions, all of which must evaluate to true.
- message
- string
- rule
- string
- // +kubebuilder:validation:XValidation
- message
- string
- rule
- string
marks a field as requiring a value for which a given expression evaluates to true.
This marker may be repeated to specify multiple expressions, all of which must evaluate to true.
- message
- string
- rule
- string
- // +nullable
marks this field as allowing the "null" value.
This is often not necessary, but may be helpful with custom serialization.
- // +optional
specifies that this field is optional, if fields are required by default.