How to display pod uid in istio-proxy access logs

Before using istio-proxy for access logs I injected k8s pod uid as env variable in my container like this :

     containers:
          env:
            - name: MY_POD_UID
              valueFrom:
                fieldRef:
                  apiVersion: v1
                  fieldPath: metadata.uid
            - name: MY_POD_NAME
              valueFrom:
                fieldRef:
                  apiVersion: v1
                  fieldPath: metadata.name

then i did “echo $MY_POD_UID” to display uid.

Now I use istio-proxy for access logs.
What is the best way to inject pod uid in istio-proxy ? how to display it with an EnvoyFilter ?

i just realized that %HOSTNAME% access log field match pod UID.
Very simple. This issue can be closed.