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Layotto sidecar injector

Sidecar injector can inject the Layotto sidecar to your pods automatically.

Prerequisites​

This Layotto state SDK client demo requires you to have the following installed on your machine:

Remember to change your current directory to ${project_path}/demo/state/k8s.

Step 1 - Setup Layotto sidecar injector on your Kubernetes cluster​

  1. Use Kind to quickly build a local Kubernetes cluster
kind create cluster --name layotto-cluster
kubectl config use-context kind-layotto-cluster
  1. Install the layotto sidecar injector chart on your cluster in the layotto-system namespace
helm install injector oci://docker.io/layotto/injector-helm --version v0.5.0 -n layotto-system --create-namespace --wait

Step 2 - Use Helm to deploy Redis on your Kubernetes cluster​

Redis is an open source, advanced key-value store. It is often referred to as a data structure server since keys can contain strings, hashes, lists, sets and sorted sets.

Here we use Redis to persist and retrieve state.

helm repo add bitnami https://charts.bitnami.com/bitnami
helm repo update
helm install redis bitnami/redis --set image.tag=6.2 --set auth.enabled=false

Step 3 - Deploy the layotto state client with the Layotto sidecar​

  1. Create a ConfigMap named layotto-config and populate its data from the config.json file
kubectl create configmap layotto-config --from-file=./config.json
  1. Deploy Layotto state SDK client App
kubectl apply -f ./state-sdk-demo.yaml

Let's take a look at the important annotations in state-sdk-demo.yaml

  • layotto/sidecar-inject: "true" - this tells the Layotto sidecar injector to inject a sidecar to this deployment.
  • layotto/config-volume: "layotto-config-vol - this tells the Layotto sidecar injector which config Volume resource to mount into layout container.

The layotto-config ConfigMap is mounted as a volume, and all contents stored in its config.json entry are mounted into the layotto sidecar container at path /runtime/configs. The successfully mounted config.json file will be used as the configuration file when Layotto starts.

View program running results​

If the following information is printed, the demo succeeded:

pods.jpg

log.jpg