Traefik: non-WWW to WWW redirect

When using Traefik as your Kubernetes ingress controller you might want to redirect any requests to your top-level domain (for instance my-domain.com) to its WWW variant (www.my-domain.com). You can use this snippet to create a Traefik IngressRoute and Traefik Middleware that will do just that.

Prerequisites

• A running instance of Traefik v2 in a Kubernetes cluster
• kubectl access to the Kubernetes cluster
• External IP address of the server/VM for testing

Snippet

apiVersion: traefik.containo.us/v1alpha1
kind: IngressRoute
metadata:
  name: my-domain-com-www-redirect # Change this
  namespace: default # Change this?
spec:
  entryPoints:
    - websecure # Change this?
  routes:
    - kind: Rule
      match: Host(`my-domain.com`) # Change this
      middlewares:
        - name: redirect-to-www
          namespace: traefik
      services:
        - kind: TraefikService
          name: noop@internal
---
apiVersion: traefik.containo.us/v1alpha1
kind: Middleware
metadata:
  name: redirect-to-www
  namespace: traefik
spec:
  redirectRegex:
    permanent: true
    regex: "^https?://(?:www\\.)?(.+)"
    replacement: "https://www.${1}"

Usage

1. Save the snippet above to a file called my-domain-com-www-redirect.yaml. You can download it here

2. Make the necessary changes

3. Create the resources:

   kubectl apply -f my-domain-com-www-redirect.yaml
   

4. Try it out with:

   curl -v https://my-domain.com/ --resolve my-domain.com:443:{your server IP}
   # 301 Moved Permanently
   # Location: https://www.my-domain.com/
   

Notes

In case you’ve enabled the providers.kubernetesCRD.ingressClass in the static configuration, you will have to add the kubernetes.io/ingress.class annotation to the IngressRoute.