--- title: List Entry description: A template designed to let you perform list checking operations. location: https://istio.io/docs/reference/config/policy-and-telemetry/templates/listentry.html layout: protoc-gen-docs generator: protoc-gen-docs aliases: - /docs/reference/config/template/listentry.html number_of_entries: 1 ---

The `listentry` template is designed to let you perform list check operations with the list adapter.

Example config:

    apiVersion: "config.istio.io/v1alpha2"
    kind: instance
    metadata:
      name: appversion
      namespace: istio-system
    spec:
      compiledTemplate: listentry
      params:
        value: source.labels["version"]

## Template

The `listentry` template is used to verify the presence/absence of a string within a list.

When writing the configuration, the value for the fields associated with this template can either be a literal or an expression. Please note that if the datatype of a field is not istio.policy.v1beta1.Value, then the expression’s inferred type must match the datatype of the field.

Field | Type | Description
--- | --- | ---
`value` | `istio.policy.v1beta1.Value` | Specifies the entry to verify in the list. This value can either be a string or an IP address.