ArgoCD

Demo - Kubernetes ArgoCD

Install ArgoCD

Install Argo CD in the Kubernetes cluster
https://argo-cd.readthedocs.io/en/stable/getting_started?_gl=1*j1x42g*_ga*MTk3MjE0ODg5MS4xNjk0NjAyMDk3*_ga_5Z1VTPDL73*MTY5NDYwMjEwNS4xLjAuMTY5NDYwMjEwOS4wLjAuMA..
```
kubectl create namespace argocd
kubectl apply -n argocd -f https://raw.githubusercontent.com/argoproj/argo-cd/stable/manifests/install.yaml
```
This will create a new namespace, argocd, where Argo CD services and application resources will live.
Install Argo CD CLI
https://argo-cd.readthedocs.io/en/stable/cli_installation/
Access The Argo CD API Server
By default, the Argo CD API server is not exposed with an external IP. To access the API server, choose one of the following techniques to expose the Argo CD API server:
Service Type: Load Balancer
Change the argocd-server service type to LoadBalancer:
```
kubectl patch svc argocd-server -n argocd -p '{"spec": {"type": "LoadBalancer"}}'
```
Port Forwarding
Kubectl port-forwarding can also be used to connect to the API server without exposing the service.
```
kubectl port-forward svc/argocd-server -n argocd 8080:443
```
The API server can then be accessed using https://localhost:8080
Login Using The CLI
The initial password for the admin account is auto-generated and stored as clear text in the field password in a secret named argocd-initial-admin-secret in your Argo CD installation namespace. You can simply retrieve this password using the argocd CLI:
```
argocd admin initial-password -n argocd
```
Using the username admin and the password from above, login to Argo CD’s IP or hostname:
```
argocd login <ARGOCD_SERVER>
```
Change the password using the command:
```
argocd account update-password
```

Setup the Git repo

Create a git repo

https://github.com/larsappel/ArgoCD.git

Create App in ArgoCD

Point to git repo
Sync

Github Action

Enable the workflow action to update the repo:
(Repo) Settings > Actions > General > Workflow permissions > Read and write permissions > Save
Don´t forget to make the Github Package registry public
You need a PAT Personal Access Token (classic) set in secret GH_TOKEN inn the workflow below

Put the app and the manifests in the same repo but in different directories:

ToDoApp (including the Dockerfile)
ToDoApp-K8S-Manifests

The github action will be triggered by a change in the application
Build a new Docker image and upload to the Github Package registry

Update the manifest with the new image version

build-push-image.yaml

name: Build and Push Docker Image

on:
  push:
    branches:
      - main
    paths:
    - 'ToDoApp/**'
  workflow_dispatch:

jobs:
  build:
    runs-on: ubuntu-latest

    steps:
    # Checkout the repository
    - name: Checkout code
      uses: actions/checkout@v4

    # Login to GitHub Container Registry
    - name: Login to GitHub Container Registry
      uses: docker/login-action@v1
      with:
        registry: ghcr.io
        username: ${{ github.actor }}
        password: ${{ secrets.GH_TOKEN }}

    # Build and push the Docker image
    - name: Build and Push Docker image
      run: |
        cd ToDoApp
        docker build -t ghcr.io/larsappel/todoapp:${{ github.sha }} .
        docker push ghcr.io/larsappel/todoapp:${{ github.sha }}

    # Update the Kubernetes manifests to use the new image tag
    - name: Update Kubernetes manifests
      run: |
        sed -i 's|ghcr.io/larsappel/todoapp:.*|ghcr.io/larsappel/todoapp:${{ github.sha }}|' ToDoApp-K8S-Manifests/todo-deployment.yaml

    # Commit and push the updated manifests back to the repository
    - name: Commit and push updated manifests
      run: |
        git config --global user.name "GitHub Actions"
        git config --global user.email "github-actions@github.com"
        git add ToDoApp-K8S-Manifests/todo-deployment.yaml
        git commit -m "Update webapp image to ${{ github.sha }}"
        git push

Continue to create an App in ArgoCD as before

Use portforwarding to open ArgoCD at https://localhost:/login
Open in a private browser window if you encounter problems

Deploy on GKE

Prerequisites

Install Lens

Install ArgoCD with Helm in Lens
Go to secrets and check the password
Port forward the argocd-server and browse to thee UI (user: admin / password:
Create App in ArgoCD as before