K3S环境下Traefik路径前缀路由后重定向失败问题咨询

针对服务内部重定向丢失前缀导致路由失败的问题，无需修改服务配置，完全通过Traefik中间件即可解决，核心思路是在请求阶段剥离前缀传给服务，同时在响应阶段修正重定向头和页面内的绝对路径。

步骤1：为每个服务创建专属中间件 #

为每个前缀（/speed、/nginx、/jenkins）单独配置中间件，同时处理请求前缀剥离和响应重定向修正：

针对openspeedtest的中间件 #

apiVersion: traefik.containo.us/v1alpha1
kind: Middleware
metadata:
  name: speed-prefix-handler
spec:
  # 剥离请求前缀，传给服务的路径不带/speed
  stripPrefix:
    prefixes:
      - /speed
  # 修改服务返回的Location重定向头，为根路径加上/speed前缀
  headersRegexReplace:
    regex: ^Location: /(.*)
    replacement: Location: /speed/$1
  # 可选：如果页面内有绝对路径链接（如<a href="/test">），添加此规则修改响应体中的路径
  responseModifier:
    body:
      replacements:
        - regex: '(href|src)="/(.*?)"'
          replacement: '$1="/speed/$2"'

针对nginx的中间件 #

apiVersion: traefik.containo.us/v1alpha1
kind: Middleware
metadata:
  name: nginx-prefix-handler
spec:
  stripPrefix:
    prefixes:
      - /nginx
  headersRegexReplace:
    regex: ^Location: /(.*)
    replacement: Location: /nginx/$1
  responseModifier:
    body:
      replacements:
        - regex: '(href|src)="/(.*?)"'
          replacement: '$1="/nginx/$2"'

针对jenkins的中间件 #

apiVersion: traefik.containo.us/v1alpha1
kind: Middleware
metadata:
  name: jenkins-prefix-handler
spec:
  stripPrefix:
    prefixes:
      - /jenkins
  headersRegexReplace:
    regex: ^Location: /(.*)
    replacement: Location: /jenkins/$1

步骤2：配置Ingress关联中间件 #

由于K8s标准Ingress不支持路径级别的中间件配置，推荐拆分每个服务为单独的Ingress，或者使用Traefik专属的IngressRoute资源（更灵活）。

方案A：拆分K8s标准Ingress #

# openspeedtest的Ingress
---
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: openspeedtest-ingress
  annotations:
    traefik.ingress.kubernetes.io/router.middlewares: default-speed-prefix-handler@kubernetescrd
spec:
  rules:
    - http:
        paths:
          - path: /speed
            pathType: Prefix
            backend:
              service:
                name: openspeedtest-service
                port:
                  number: 80

# nginx的Ingress
---
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: nginx-ingress
  annotations:
    traefik.ingress.kubernetes.io/router.middlewares: default-nginx-prefix-handler@kubernetescrd
spec:
  rules:
    - http:
        paths:
          - path: /nginx
            pathType: Prefix
            backend:
              service:
                name: nginx-service
                port:
                  number: 80

# jenkins的Ingress
---
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: jenkins-ingress
  annotations:
    traefik.ingress.kubernetes.io/router.middlewares: default-jenkins-prefix-handler@kubernetescrd
spec:
  rules:
    - http:
        paths:
          - path: /jenkins
            pathType: Prefix
            backend:
              service:
                name: jenkins-service
                port:
                  number: 80

方案B：使用Traefik IngressRoute（推荐） #

IngressRoute是Traefik的CRD资源，支持路由级别的中间件配置，结构更简洁：

apiVersion: traefik.containo.us/v1alpha1
kind: IngressRoute
metadata:
  name: services-ingressroute
spec:
  entryPoints:
    - web
  routes:
    - match: Host(`somedomain.com`) && PathPrefix(`/speed`)
      kind: Rule
      middlewares:
        - name: speed-prefix-handler
      services:
        - name: openspeedtest-service
          port: 80
    - match: Host(`somedomain.com`) && PathPrefix(`/nginx`)
      kind: Rule
      middlewares:
        - name: nginx-prefix-handler
      services:
        - name: nginx-service
          port: 80
    - match: Host(`somedomain.com`) && PathPrefix(`/jenkins`)
      kind: Rule
      middlewares:
        - name: jenkins-prefix-handler
      services:
        - name: jenkins-service
          port: 80

方案说明 #

• stripPrefix：将请求的前缀（如/speed）剥离后转发给后端服务，确保服务接收到的是预期的路径（如/）。
• headersRegexReplace：捕获服务返回的Location重定向头，将根路径开头的地址替换为带前缀的路径（如将Location: /改为Location: /speed/），解决重定向丢失前缀的问题。
• responseModifier（可选）：修正页面内的绝对路径链接，避免用户点击链接后跳转到无前缀的路径。此功能需要Traefik v2.4及以上版本支持。

内容的提问来源于stack exchange，提问作者Artem