DEMO Setting up the MySQL Database

In this guide, we’ll walk through deploying a MySQL database on Kubernetes using Flux’s GitRepository and Kustomization controllers along with Kustomize manifests. By following these steps, you will:

1. Update the PHP application to connect to MySQL
2. Define Kubernetes manifests for MySQL
3. Use Flux GitRepository and Kustomization resources for GitOps deployment

1. Update the PHP Application

On the 7-demo branch, the PHP app has been extended to store high scores in a MySQL database. The connection logic in highscore.php now looks like:

<?php
$servername = "mysql.database.svc.cluster.local";
$username   = "root";
$password   = "mysql-password-0123456789";
$dbname     = "bricks";

// Create connection
$conn = new mysqli($servername, $username, $password, $dbname);
if ($conn->connect_error) {
    die("Connection failed: " . $conn->connect_error);
}

// Escape and use the posted high score
$highscore = mysqli_real_escape_string($conn, $_POST['highscore']);
// ... (insert logic)

Ensure you’re on the correct branch in your terminal:

git checkout 7-demo
# root ~/bb-app-source 7-demo [?]

2. Inspect the Infrastructure Branch

All MySQL manifests and namespace definitions reside in the infrastructure branch under the database/ directory:

git checkout infrastructure
ls
# bitnami-sealed-secrets/  cert-manager/  database/  ingress-nginx/  block-buster-helm-app-7.7.1.tgz

Inside database/, you’ll find:

• namespace.yaml
• configmap.yaml
• secret.yaml
• deployment.yaml
• service.yaml
• PersistentVolume and PersistentVolumeClaim manifests

# database/secret.yaml
apiVersion: v1
kind: Secret
metadata:
  name: secret-mysql
  namespace: database
stringData:
  password: mysql-password-0123456789

3. Create a Flux GitRepository Source

Define a GitRepository resource in your Flux cluster repo (flux-clusters/dev-cluster) to track the infrastructure branch:

# infra-source-git.yml
apiVersion: source.toolkit.fluxcd.io/v1beta2
kind: GitRepository
metadata:
  name: infra-source-git
  namespace: flux-system
spec:
  interval: 1m0s
  url: https://github.com/sidd-harth-2/bb-app-source
  ref:
    branch: infrastructure

Export it with the Flux CLI:

cd ~/block-buster/flux-clusters/dev-cluster
flux create source git infra-source-git \
  --url https://github.com/sidd-harth-2/bb-app-source \
  --branch infrastructure \
  --timeout 10s \
  --export > infra-source-git.yml

4. Create a Flux Kustomization

Use a Kustomization to apply resources under database/:

# infra-database-kustomize-git-mysql.yml
apiVersion: kustomize.toolkit.fluxcd.io/v1beta2
kind: Kustomization
metadata:
  name: infra-database-kustomize-git-mysql
  namespace: flux-system
spec:
  interval: 1m40s
  path: ./database
  prune: true
  sourceRef:
    kind: GitRepository
    name: infra-source-git
  targetNamespace: database

Generate via:

flux create kustomization infra-database-kustomize-git-mysql \
  --source GitRepository/infra-source-git \
  --path ./database \
  --prune true \
  --target-namespace database \
  --interval 100s \
  --export > infra-database-kustomize-git-mysql.yml

Commit and push both manifests:

git add infra-source-git.yml infra-database-kustomize-git-mysql.yml
git commit -m "Add MySQL DB source and kustomization"
git push

5. Reconcile and Verify

Force Flux to apply changes immediately:

flux reconcile source git infra-source-git
flux reconcile kustomization infra-database-kustomize-git-mysql

Check that the database namespace is created:

kubectl get ns
# NAME        STATUS   AGE
# database    Active   <age>

Inspect Flux sources and kustomizations:

flux get sources git infra-source-git
flux get kustomizations infra-database-kustomize-git-mysql

Verify MySQL resources in database namespace:

kubectl -n database get all,cm,secret
# NAME                                READY   STATUS    RESTARTS   AGE
# pod/mysql-xxxxxxxxxx-xxxxx          1/1     Running   0          <age>
# service/mysql                       ClusterIP 10.96.x.x 3306/TCP    <age>
# deployment.apps/mysql               1/1       Available   0        <age>
#
# NAME                             AGE
# configmap/mysql-initdb-config    <age>
# secret/secret-mysql              <age>

The MySQL database is now up and running! Next, we’ll pull the PHP application image from an OCI registry and deploy it with Flux.

Flux Resources Overview

Links and References

• Flux GitRepository Documentation
• Flux Kustomization Documentation
• Kubernetes Secrets
• MySQL Official Docs