--- title: List Entry overview: A template designed to let you perform list checking operations. location: https://istio.io/docs/reference/config/template/listentry.html layout: protoc-gen-docs number_of_entries: 1 ---

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

## 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.mixer.adapter.model.v1beta1.Value, then the expression’s inferred type must match the datatype of the field.

Example config:

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

Field | Type | Description
--- | --- | ---
`value` | `string` | Specifies the entry to verify in the list.