Traefik Has a Free API: The Cloud-Native Reverse Proxy That Auto-Discovers Services

#traefik #devops #docker #kubernetes

Nginx needs manual config updates for every service. Traefik discovers your Docker containers and Kubernetes services automatically.

What Is Traefik?

Traefik is a modern reverse proxy and load balancer that auto-discovers services from Docker, Kubernetes, Consul, and more. Add a label to your container — Traefik routes traffic to it.

Docker Auto-Discovery

# docker-compose.yml
services:
  traefik:
    image: traefik:v3.0
    command:
      - "--api.insecure=true"
      - "--providers.docker=true"
      - "--entrypoints.web.address=:80"
      - "--entrypoints.websecure.address=:443"
      - "--certificatesresolvers.le.acme.email=you@example.com"
      - "--certificatesresolvers.le.acme.storage=/letsencrypt/acme.json"
      - "--certificatesresolvers.le.acme.httpchallenge.entrypoint=web"
    ports:
      - "80:80"
      - "443:443"
    volumes:
      - /var/run/docker.sock:/var/run/docker.sock

  my-app:
    image: my-app:latest
    labels:
      - "traefik.enable=true"
      - "traefik.http.routers.myapp.rule=Host(\`myapp.example.com\`)"
      - "traefik.http.routers.myapp.tls.certresolver=le"

Start the container → Traefik detects it → routes myapp.example.com → auto-HTTPS. No config reload.

Kubernetes Auto-Discovery

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: my-app
  annotations:
    traefik.ingress.kubernetes.io/router.entrypoints: websecure
spec:
  rules:
    - host: myapp.example.com
      http:
        paths:
          - path: /
            pathType: Prefix
            backend:
              service:
                name: my-app
                port:
                  number: 80

Middleware

labels:
  # Rate limiting
  - "traefik.http.middlewares.ratelimit.ratelimit.average=100"
  # Basic auth
  - "traefik.http.middlewares.auth.basicauth.users=admin:$$apr1$$..."
  # Redirect HTTP to HTTPS
  - "traefik.http.middlewares.redirect.redirectscheme.scheme=https"
  # Strip prefix
  - "traefik.http.middlewares.strip.stripprefix.prefixes=/api"