talos-cluster/kubernetes/components/connect/mysql

MySQL Connection Component

This Kustomize component provides a standardized way for applications to connect to the shared MySQL database cluster.

Features

• Injects standard database connection environment variables.
• Supports Deployment, StatefulSet, and HelmRelease (standard bjw-s app-template structure).
• Configurable via a local mysql-secret.

Environment Variables

The following variables are injected into the application containers:

Variable	Source / Value	Description
DB_HOST	mysql-innodbcluster-router.database-system.svc.cluster.local	The internal DNS name for the MySQL router.
DB_PORT	3306	The default MySQL port.
DB_USER	Secret mysql-secret, key DB_USER	Database username.
DB_PASSWORD	Secret mysql-secret, key DB_PASSWORD	Database password.
DB_NAME	Secret mysql-secret, key DB_NAME	Name of the database.

Usage

1. Add the component to kustomization.yaml

In your application's kustomization.yaml, add the component:

components:
  - ../../components/connect/mysql

2. Create the required secret

Ensure a secret named mysql-secret exists in the application's namespace with the following keys:

apiVersion: v1
kind: Secret
metadata:
  name: mysql-secret
stringData:
  DB_USER: "your-user"
  DB_PASSWORD: "your-password"
  DB_NAME: "your-database"

3. Overriding defaults

If you need to use a different secret name or override specific variables, you can define them directly in your resource's env section. Kustomize will prioritize or merge these depending on the patch type.

For HelmRelease using the bjw-s template, ensure your controller is named main and container is named main for the patch to apply automatically.

Resource Compatibility

• Deployments: Targets containers named app.
• StatefulSets: Targets containers named app.
• HelmReleases: Targets spec.values.controllers.main.containers.main.