Medium - Traefik as an ingress controller on minikube with kustomize & helm

0--values.yaml

# Cf. https://github.com/helm/charts/blob/master/stable/traefik/values.yaml
rbac:
  enabled: true
dashboard:
  enabled: true
  domain: traefik.local.minikube.com
  serviceType: NodePort
serviceType: NodePort

1--helm-template-to-native-k8s-resource.sh

# Pre-requisite:
# - You have minikube with kubernetes > 1.14 up & running
# - You have setup tiller on minikube
# - You **don't** have enabled the minikube ingress addon
# - You have kubectl > 1.14

# We need to have a copy of the helm chart locally
helm fetch --untar --untardir chart 'stable/traefik'

# We then export the template as native Kurbenetes resources
helm template \
    --namespace kube-system \
    --values 0--values.yaml \
    --name traefik-ingress-controller \
    helm/traefik/chart/traefik > traefik-helm-template.yaml

2--kustomization.yaml

# This is where the magic happens ✨
apiVersion: kustomize.config.k8s.io/v1beta1
kind: Kustomization

resources:
- traefik-helm-template.yaml
patches:
- minikube-ingress-controller-patch.yaml
patchesJson6902:
- target:
    group: apps
    version: v1
    kind: Deployment
    name: traefik-ingress-controller
  path: delete-useless-fields.yaml

3--minikube-ingress-controller-patch.yaml

# This file will add hostPorts and NET_BIND_SERVICE Security Context Capability
apiVersion: apps/v1
kind: Deployment
metadata:
  name: traefik-ingress-controller
spec:
  template:
    spec:
      containers:
      - name: traefik-ingress-controller
        ports:
        - containerPort: 80
          hostPort: 80
        - containerPort: 8880
          hostPort: 8880
        - containerPort: 443
          hostPort: 443
        - containerPort: 8080
          hostPort: 8080
        securityContext:
          capabilities:
            drop:
            - ALL
            add:
            - NET_BIND_SERVICE

4--delete-useless-fields.yaml

# Cf. https://kubectl.docs.kubernetes.io/pages/app_customization/customizing_arbitrary_fields.html
# This path deletes fields that we don't need using "patchesJson6902"
# The syntax is not intuitive but the proposed standard (https://tools.ietf.org/html/rfc6902) is enough to get things done

# This operation removes the port 8880 (index 1)
- op: remove
  path: /spec/template/spec/containers/0/ports/1
  
# Careful: each operation is done sequentially so you have
#          to take into account the operations before to determine
#          how to manipulate paths
# In our example we wanted to delete the port 8080 below (index 3)
# but its the index has changed since the index 1 has been deleted above
- op: remove
  path: /spec/template/spec/containers/0/ports/2

5--deploy-all-the-things.sh

# Everything is setup, we will now apply the base helm chart
# and the patches we declare in our kustomization.yaml
kubectl apply --kustomize .