Before deploying to GKE, you should always test your application, as well as your Kubernetes resource files (secrets, deployments, services, namespaces, routerules, etc.) on minikube.
# create cluster
minikube start
minikube status
# install Istio 0.7.1 without mTLS
kubectl apply -f $ISTIO_HOME/install/kubernetes/istio.yaml
# deploy v2 to local minikube dev environment
sh ./part1-create-environment.sh
sh ./part2-deploy-v2.sh
sh ./part3-smoke-test.sh
# kubernetes dashboard
minikube dashboardbrew cask upgrade minikube
minikube version
minikube get-k8s-versions
eval $(minikube docker-env)
docker ps
kubectl config use-context minikube
kubectl get nodes
kubectl get namespaces