GitOps Sample

This is a sample project to demonstrate GitOps with ArgoCD.

Instructions

1. Create a K8s cluster

2. Install ingress-nginx

   helm repo add ingress-nginx https://kubernetes.github.io/ingress-nginx
   helm repo update
   helm install ingress-nginx ingress-nginx/ingress-nginx --create-namespace --namespace ingress-nginx

3. Get the nginx loadbalancer service's external IP

   $ kubectl get svc -n ingress-nginx
   NAME                                 TYPE           CLUSTER-IP      EXTERNAL-IP     PORT(S)                      AGE
   ingress-nginx-controller-admission   ClusterIP      10.43.132.65    <none>          443/TCP                      3m12s
   ingress-nginx-controller             LoadBalancer   10.43.172.201   **74.220.19.189**   80:31297/TCP,443:32408/TCP   3m12s

   Add a DNS entry of A type for your domain (in this case: gitops.arshsharma.com) to point to this IP.

4. Install ArgoCD

   kubectl create namespace argocd
   kubectl apply -n argocd -f https://raw.githubusercontent.com/argoproj/argo-cd/stable/manifests/install.yaml

   To access the Argo CD UI:

   kubectl port-forward svc/argocd-server -n argocd 8080:443

   Login to localhost:8080 with username admin and password you get via running:

   kubectl -n argocd get secret argocd-initial-admin-secret -o jsonpath="{.data.password}" | base64 -d

   Or if you have argocd CLI installed, you can run:

   argocd admin initial-password -n argocd

   This is supposed to be a one time use password and it is recommended you change this.

5. Click New App from the Argo CD UI and click edit as YAML and copy paste the config in /apps/go-server-prod.yaml and click create. And then click sync.

   Now we are at the stage when if you change the tag in chart/values.yaml and commit and push, Argo CD will detect that its out of sync and you can click sync from the UI to sync it.

6. Next step is to automate things and for that we will use GitHub Actions. Create a DockerHub token and the following repo secrets in GitHub:

   • DOCKERHUB_USERNAME
   • DOCKERHUB_TOKEN

7. In the repo settings -> Actions -> General -> Workflow permissions -> Give it read and write permissions so that our action can commit changes to the repo.

Since this is a mono repo example we would have to do:

git fetch origin   
git rebase origin/main

It is ideal to separate the application code and application config in different repos.