Deploy via FluxCD

FluxCD is a continuous delivery tool for Kubernetes. It is used to keep Kubernetes in sync with configuration sources such as Git repositories.

StarlingX does not have FluxCD CLI, but it does have FluxCD resources which can be used to deploy applications.

Using FluxCD resources you can deploy your applications and apply GitOps to them.

Create a Source Controller

The Source Controller is a FluxCD resource that serves as the pivotal point for acquiring artifacts necessary for deployment. It is crucial for ensuring easy access to important elements such as source code, configuration files, and other essential components for deploying your application. Essentially, it acts as the gateway facilitating the acquisition process, guaranteeing that your application has the requisite resources for deployment.

There are five types of Source Controllers, in this example GitRepository will be used. The GitRepository is a type of Source Controller that is used to manage applications defined within Git repositories.

In the active controller, run:

cat <<EOF > gitrepository.yaml
apiVersion: source.toolkit.fluxcd.io/v1
kind: GitRepository
metadata:
  name: <source-controller-name>
spec:
  interval: 5m
  url: <git-repository-url>
  ref:
    branch: <branch>

EOF

$ kubectl apply -f gitrepository.yaml

The above command creates a GitRepository resource, you can check by running:

$ kubectl get gitrepositories

Create a Helm Controller

For deploying applications via FluxCD, create a Helm Controller or Kustomize Controller, each one has its specifications.

For deploying via Helm, create a HelmRelease resource.

cat <<EOF > helmrelease.yaml
apiVersion: "helm.toolkit.fluxcd.io/v2"
kind: HelmRelease
metadata:
  name: <helm-release-name>
spec:
  releaseName: <helm-release-name>
  interval: 5m
  chart:
    spec:
      chart: <helm-chart-path> # Relative path of the Helm chart inside the repo.
      version: <helm-chart-version>
      sourceRef:
        kind: GitRepository
        name: <source-controller-name>
    values: # Override values for the Helm chart.
      foo:
        bar: value

EOF

$ kubectl apply -f helmrelease.yaml

This command creates a HelmChart and a HelmRelease resources, the HelmChart stores the Helm chart loaded from the GitRepository, and the HelmRelease is responsible for applying Helm actions, such as configuring, installing or upgrading the Helm Chart.

You can check if the resources were created by running:

$ kubectl get helmcharts

$ kubectl get helmreleases

To check the application deployment:

$ kubectl get all

Modify the Application Values

To modify values of your HelmRelease, you can edit the spec.values section of helmrelease.yaml file and apply it again:

$ kubectl apply -f helmrelease.yaml

This will cause the controller to perform Helm actions on the deployment.