--- 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.
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"]