gitops-examples

This repository is to share what I had learned in the last weeks about #ArgoCD and #GitOps.

Sugestions are welcome.

Complete examples using CR, Charts and Kustomize.

All examples using Quarkus/MicroProfile application. Simple application that exposes /hello with a customizable property quarkus.app.custom.message

• Source code: quarkus-app folder in this repository
• Image: viniciusfcf/gitops-quarkus-app-jvm

Prerequisites

The examples contained in this section require.

• OpenShift >= 4.10 up and running
• the oc OpenShift client command-line tool

Content

Folder	Comments
env	Files to configure OpenShift
quarkus-app	Quarkus application
plain-yaml	GitOps examples using managed Custom Resources
kustomize	GitOps examples using Kustomize
helm	GitOps examples using Helm Charts

Installing ArgoCD

Login into Openshift

oc login --token=<TOKEN> --server=<SERVER>

Install GitOps (ArgoCD) Operator

oc apply -f env/gitops-operator.yaml

Grant permissions for an Argo CD instance to manage cluster configuration.

oc apply -f env/cluster-role.yaml

oc apply -f env/cluster-role-binding.yaml

Print ArgoCD route

oc get route openshift-gitops-server -n openshift-gitops -o jsonpath='{.spec.host}'

Extract ArgoCD admin password

oc -n openshift-gitops extract secret/openshift-gitops-cluster --to=-

Adding applications to ArgoCD

Plain YAML

create plain-yaml application in ArgoCD

oc create -f env/argocd-app-plain-yaml.yaml

Print Route

APP_HOST=$(oc get route my-app-name-route -n my-app-ns -o jsonpath='{.spec.host}')

Call endpoint

curl $APP_HOST/hello

Serverless Plain YAML

Install Serverless (KNative) Operator

oc apply -f env/serverless-operator.yaml

Configure KnativeServing

oc apply -f env/serverless-serving.yaml

Create plain-yaml Serverless application in ArgoCD

oc apply -f env/argocd-app-serverless-plain-yaml.yaml

Print Serverless Route

oc get ksvc my-app-serverless -n my-app-ns

Kustomize

oc create -f env/argocd-app-kustomize-dev.yaml

oc create -f env/argocd-app-kustomize-qa.yaml

oc create -f env/argocd-app-kustomize-prd.yaml

Helm chart

oc create -f env/argocd-app-helm.yaml

Pros e Cons

plain-yaml

• Does not update deployment if configmap is updated
• So many files, worst, yamls files

kustomize

• Simplifies configuration, mainly with more than one environment to deploy
• Update deployment if configmap is updated using configMapGenerator
• Think twice before update base yamls, they affect all environments.

helm

• Too complex to use with ArgoCD, besides the yaml files in git we have versions of the charts. Sounds like an unnecessary step if you are going to use ArgoCD.

Building my helm chart

• Create the folder charts In my repository viniciusfcf.github.io
• Package (Working dir: <BASE>/gitops-examples/helm/dev)

  helm package -d <DIR>/viniciusfcf.github.io/charts .
  

• Generate index.yaml repo file

  helm repo index <DIR>/viniciusfcf.github.io/charts
  

• Push index.yaml and *.tgz files to git