#!/bin/sh

namespace=$1
downstreamNamespace=$2
echo $namespace
echo $downstreamNamespace

allPods=`kubectl get pods -n $namespace | awk '/Running/ {print $1}'`
allPods=($allPods)

for pod in "${allPods[@]}"
do
        containers=`kubectl get pods/${pod}  -o=jsonpath="{.spec.containers[*].name}" -n $namespace`
        containers=($containers)
        for container in "${containers[@]}"
        do
                dnsResearch=`kubectl exec -i pods/${pod} -n $namespace -- cat /etc/resolv.conf`
                isModified=0
                awkResearch=`echo $dnsResearch | awk '/'$namespace'.svc.cluster.local *'$downstreamNamespace'.*/ {print}'`
                if [ -n "$awkResearch" ]; then
                        isModified=1
                fi

                if [ $isModified -eq 0 ]; then
                        dnsResearch=`echo "${dnsResearch/$namespace.svc.cluster.local/$namespace.svc.cluster.local $downstreamNamespace.svc.cluster.local}"`
                        kubectl exec -i pods/${pod} -c ${container} -n $namespace -- /bin/sh -c "echo '${dnsResearch}'>/etc/resolv.conf"
                fi
        done
done