#!/bin/bash

PATTERN='for-example-a-kafka-topic-name-to-look-for'

for ns in $(kubectl get ns | awk '{if ($1 !~ /^NAME|kube-/) {print $1}}')
do
  echo "Looking into $ns"
  kubectl exec -n "$ns" -c nifi nifi-0 -- zgrep "$PATTERN" permanent_configs/flow.xml.gz 2>/dev/null
done