gRPC for microservices in Kubernetes

I have been experimenting with gRPC for some time now. I wrote some articles to cover the basics like What is gRPC? SSL/TLS Auth in gRPC, and communication patterns used in gRPC. In these topics I went through some of the advantages of gRPC over traditional REST API for inter-service communication — especially in a distributed architecture. The crux is — gRPC offers great performance using Protobuf and natively supports uni and bi directional streaming.

I used an analogy of calculator server and clients calling out arithmetic operations from this server using gRPC protocol, in all the previous blogs. In this blog, I take the same example to take the next step — deploying these services on K8s cluster to demonstrate how you can use gRPC in Kubernetes context. Specifically, in this post I will:

1. Containerize the client and server applications using Docker
2. Prepare Kubernetes deployment YAMLs for these services
3. Prepare Kubernetes service YAML to expose the calculator server
4. Make sure uni and bidirectional communication is enabled between client and server

Please note that there are multiple ways gRPC is used like — in Ingress load balancers, service meshes, etc. In fact, K8s also uses gRPC to enable efficient communication between kubelet and CRI (Container…