8. flux tutorial

Like the tutorials in [flux-01] and [flux-02], this sets up a repository for flux and deploys podinfo, but with the following differences:

• Repositories are in gitlab

• The podinfo repository is private

8.1. Install flux and create a kubernetes cluster

• Install flux with brew (macOS):

  brew install fluxcd/tap/flux
  

• Add flux completion to fish (ref. https://fluxcd.io/docs/cmd/flux_completion_fish/ )

• Create a kubernetes cluster (for Digital Ocean ref. https://docs.digitalocean.com/products/kubernetes/how-to/create-clusters/ )

• Update kubeconfig to use created cluster (https://docs.digitalocean.com/products/kubernetes/how-to/connect-to-cluster/ )

• Check flux pre-req:

  > flux check --pre
  ► checking prerequisites
  ✔ kubectl 1.21.0 >=1.18.0-0
  ✔ Kubernetes 1.21.2 >=1.16.0-0
  ✔ prerequisites checks passed
  

8.2. Bootstrap flux

• Run flux bootstrap command

  > flux bootstrap gitlab \
     --ssh-hostname=gitlab.com \
     --owner=your_gitlab_user --personal \
     --repository=flux-test \
     --branch=master \
     --path=clusters/my-cluster
  
  ► connecting to https://gitlab.com
  ...
  ✔ all components are healthy
  

8.3. Deploy podinfo (from a private repo)

• Fork podinfo to a private repo (e.g., https://gitlab.com/your_gitlab_user/podinfo)

• Clone bootstrapped flux repository

• Create source git repository manifest for podinfo

  flux-test (master)> flux create source git podinfo \
     --url=https://gitlab.com/your_gitlab_user/podinfo \
     --branch=master \
     --interval=30s \
     --export > ./clusters/my-cluster/podinfo-source.yaml
  

• Because the podinfo repo is private, fix the url and add a secretRef in the GitRepository manifest: From:

  ---
  apiVersion: source.toolkit.fluxcd.io/v1beta1
  kind: GitRepository
  metadata:
  name: podinfo
  namespace: flux-system
  spec:
  interval: 30s
  ref:
     branch: master
  url: https://gitlab.com/your_gitlab_user/podinfo
  

  To:

  ---
  apiVersion: source.toolkit.fluxcd.io/v1beta1
  kind: GitRepository
  metadata:
  name: podinfo
  namespace: flux-system
  spec:
  interval: 30s
  ref:
     branch: master
  url: ssh://git@gitlab.com/your_gitlab_user/podinfo
  secretRef:
     name: flux-system
  

• Create kustomization for podinfo

  flux-test (master)> flux create kustomization podinfo \
     --source=podinfo \
     --path="./kustomize" \
     --prune=true \
     --validation=client \
     --interval=5m \
     --export > ./clusters/my-cluster/podinfo-kustomization.yaml
  

• Commit and push

• Check flux logs and get kustomizations

  > flux logs --kind=Kustomization --name=podinfo
  
  > flux get kustomizations
  

• Forward port to access the application

  > kubectl get deployments,svc
  NAME                      READY   UP-TO-DATE   AVAILABLE   AGE
  deployment.apps/podinfo   2/2     2            2           5m25s
  
  NAME                 TYPE        CLUSTER-IP      EXTERNAL-IP   PORT(S)             AGE
  service/kubernetes   ClusterIP   10.245.0.1      <none>        443/TCP             3d
  service/podinfo      ClusterIP   10.245.150.90   <none>        9898/TCP,9999/TCP   5m25s
  
  > kubectl port-forward service/podinfo :9898
  Forwarding from 127.0.0.1:65326 -> 9898
  Forwarding from [::1]:65326 -> 9898
  

• Access port with a web browser http://localhost:65326

8.4. References

[flux-01]

Get Started with Flux (fluxcd.io) (Retrieved 2021-07-29)

[flux-02]

How To Set Up a Continuous Delivery Pipeline with Flux on DigitalOcean Kubernetes (digitalocean.com) (Retrieved 2021-07-29)