Make a regexp redirect in dynamic configuration file with Traefik v2
/etc/traefik/traefik.yml:
[...]
providers:
file:
directory: "/etc/traefik/dynamic/"
watch: true
[...]
/etc/traefik/dynamic/redirect.yml:
http:
middlewares:
redir:
redirectRegex:
permanent: true
regex: "http://old.wains.be/(.*)"
replacement: "https://new.wains.be/${1}"
routers:
redir:
rule: "HostRegexp(`old.wains.be`)"
entrypoints:
- http
middlewares:
- redir
tls:
certresolver: "letsencrypt"
service: "ThisWillNeverBeUsedButNeedsToBeThere"
services:
ThisWillNeverBeUsedButNeedsToBeThere:
loadBalancer:
servers:
- url: "http://127.0.0.1"
As you can notice, we have to declare a dummy service, otherwise the redirect will never work.
NOTE: if your old address used to be as https, Traefik should have a valid certificate for the URL.
Docker labels
If you want to make the same with labels on Docker containers, you have to apply labels to a dedicated dummy container.
Here’s an Ansible playbook I’ve used to create the dummy container using whoami image.
---
- name: redirect
hosts: vps
become: true
tasks:
- name: whoami
docker_container:
name: whoami
image: 'containous/whoami'
networks:
- name: UserDefinedBridge
purge_networks: yes
labels:
traefik.enable: "true"
ansible: "true"
traefik.http.routers.prsite.rule: "HostRegexp(`old.wains.be`)"
traefik.http.routers.prsite.middlewares: "pr-redirect"
traefik.http.routers.prsite.entrypoints: "https"
traefik.http.routers.prsite.tls: "true"
traefik.http.middlewares.pr-redirect.redirectregex.regex: "^https://old.wains.be/(.*)"
traefik.http.middlewares.pr-redirect.redirectregex.replacement: "https://new.wains.be/$1"
traefik.http.middlewares.pr-redirect.redirectregex.permanent: "true"
The service part should not be defined since the labels are applied to the container which is the service.