Deploying a monolith
This chapter is about microservices, so why are we starting with deploying monoliths in Istio? The first answer is, because we can! There’s no reason to not get the benefits of Istio’s built-in capabilities when working with monoliths in your cluster. Even though it’s not a “microservice,” it’s still good to be able to trace through application requests, manage deployments, and so on. The second answer is, because we need to. Our microservice will need to know which user in our enterprise is calling it. To do that, Istio will need a JWT to validate. We’ll use OpenUnison to generate JWTs first so that we can call our service manually, and then so we can authenticate users from a frontend and allow it to call our service securely.
Starting with your cluster from Chapter 16, we’re now going to deploy OpenUnison. Go to the chapter17/openunison-istio directory and run deploy_openunison_istio.sh:
cd chapter17...
