Minikube Nginx Kubernetes Ingress 正在改变请求的方法答案

【问题标题】：Minikube Nginx Kubernetes Ingress is Changing the Method of RequestsMinikube Nginx Kubernetes Ingress 正在改变请求的方法
【发布时间】：2021-04-29 16:46:46
【问题描述】：

我有这个入口配置文件：

apiVersion: extensions/v1beta1
kind: Ingress
metadata:
  name: my-ingress
  annotations:
    kubernetes.io/ingress.class: "nginx"
    nginx.ingress.kubernetes.io/enable-cors: "true"
    nginx.ingress.kubernetes.io/use-regex: "true"
spec:
  rules:
  - host: mylocalhost.info
    http:
      paths:
      # NOTE: this one should come after all other routes. To avoid hijacking requests.
      - path: /api/*
        pathType: Prefix
        backend:
          serviceName: backend-default
          servicePort: 8080
      - path: /*
        pathType: Prefix
        backend:
          serviceName: frontend
          servicePort: 8080

当我打开它时，我可以让前端服务正常工作。问题是当我的前端对后端进行 API 调用时，由于某种原因，入口将请求从 GET 更改为 POST，因此我的后端返回服务器错误 (405)。

如何配置入口以保持相同的 HTTP 方法而不将其更改为 GET？

前端服务/部署

apiVersion: apps/v1
kind: Deployment
metadata:
  labels:
    app: frontend
  name: frontend
  namespace: default
spec:
  replicas: 2
  selector:
    matchLabels:
      app: frontend
  template:
    metadata:
      labels:
        app: frontend
    spec:
      imagePullSecrets:
      - name: mysecret
      containers:
      - image: gcr.io/myimage/frontend:latest
        imagePullPolicy: IfNotPresent
        name: frontend
#        resources:
#          requests:
#            cpu: "1.0"
#            memory: "1G"
#          limits:
#            cpu: "1.0"
#            memory: "1G"

apiVersion: v1
kind: Service
metadata:
  labels:
    app: frontend
  name: frontend
  namespace: default
spec:
  ports:
  - port: 8080
    protocol: TCP
    targetPort: 80
  selector:
    app: frontend
  type: ClusterIP

后端服务和部署

apiVersion: apps/v1
kind: Deployment
metadata:
  labels:
    app: backend-default
  name: backend-default
  namespace: default
spec:
  replicas: 1
  selector:
    matchLabels:
      app: backend-default
  template:
    metadata:
      labels:
        app: backend-default
    spec:
      imagePullSecrets:
      - name: mysecret
      volumes:
      - name: service-account-credentials-volume
        secret:
          secretName: gcp-service-account-credentials
          items:
          - key: sa_json
            path: sa_credentials.json
      containers:
      - image: gcr.io/mybackendimage/default:latest
        imagePullPolicy: Always
        name: backend-default
        ports:
        - containerPort: 8080
        volumeMounts:
        - name: service-account-credentials-volume
          mountPath: /etc/gcp
          readOnly: true
        envFrom:
        - configMapRef:
            name: backend-default-configmap
        - secretRef:
            name: backend-default-secrets
#        resources:
#          requests:
#            cpu: "1.0"
#            memory: "1G"
#          limits:
#            cpu: "1.0"
#            memory: "1G"
apiVersion: v1
kind: Service
metadata:
  labels:
    app: backend-default
  name: backend-default
  namespace: default
spec:
  ports:
  - port: 8080
    protocol: TCP
    targetPort: 8080
  selector:
    app: backend-default
  type: ClusterIP

NGINX Ingress 控制器的相关日志

192.168.49.1 - - [25/Jan/2021:20:41:12 +0000] "GET /static/js/131.4ccedc61d2caa2c0cdf8.js HTTP/1.1" 200 3182 "http://mylocalhost.info/" "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/87.0.4280.141 Safari/537.36" 546 0.001 [default-frontend-8080] [] 172.17.0.4:80 3182 0.000 200 fda43aed15c089c7b960f69045c891d2
192.168.49.1 - - [25/Jan/2021:20:41:24 +0000] "POST /api/v1/user/new HTTP/1.1" 302 301 "http://mylocalhost.info/user/new" "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/87.0.4280.141 Safari/537.36" 673 0.003 [default-backend-default-8080] [] 172.17.0.9:8080 301 0.004 302 63ae2df926a5acfb96202cad050248ba
192.168.49.1 - - [25/Jan/2021:20:41:24 +0000] "OPTIONS /api/v1/user/new HTTP/2.0" 204 0 "http://mylocalhost.info/user/new" "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/87.0.4280.141 Safari/537.36" 338 0.000 [default-backend-default-8080] [] - - - - 2b794c37d70b6138479a5380e0158f18
192.168.49.1 - - [25/Jan/2021:20:41:24 +0000] "GET /api/v1/user/new HTTP/2.0" 500 22 "http://mylocalhost.info/user/new" "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/87.0.4280.141 Safari/537.36" 76 0.003 [default-backend-default-8080] [] 172.17.0.9:8080 22 0.004 500 897f92a3049c81139f2e4d0ec93c2427
W0125 20:48:04.814824       8 warnings.go:67] networking.k8s.io/v1beta1 Ingress is deprecated in v1.19+, unavailable in v1.22+; use networking.k8s.io/v1 Ingress
192.168.49.1 - - [25/Jan/2021:20:51:26 +0000] "GET /user/new HTTP/1.1" 404 555 "-" "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/87.0.4280.141 Safari/537.36" 701 0.001 [default-frontend-8080] [] 172.17.0.6:80 555 0.000 404 56a62857599a4091e03f25e75b97f7cf
192.168.49.1 - - [25/Jan/2021:20:51:27 +0000] "GET /favicon.ico HTTP/1.1" 404 555 "http://mylocalhost.info/user/new" "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/87.0.4280.141 Safari/537.36" 532 0.000 [default-frontend-8080] [] 172.17.0.4:80 555 0.000 404 98bd25020f8d9e0ed8f4dc5a19419563
192.168.49.1 - - [25/Jan/2021:20:52:00 +0000] "POST /api/v1/user/new HTTP/1.1" 302 301 "http://mylocalhost.info/user/new" "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/87.0.4280.141 Safari/537.36" 673 0.003 [default-backend-default-8080] [] 172.17.0.9:8080 301 0.004 302 9d60c37ac30eabc384ee815c16940a37
192.168.49.1 - - [25/Jan/2021:20:52:00 +0000] "GET /api/v1/user/new HTTP/2.0" 500 22 "http://mylocalhost.info/user/new" "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/87.0.4280.141 Safari/537.36" 317 0.010 [default-backend-default-8080] [] 172.17.0.9:8080 22 0.008 500 6a1b724dfca5412bc24bb31c2328b01d
W0125 20:54:53.815210       8 warnings.go:67] networking.k8s.io/v1beta1 Ingress is deprecated in v1.19+, unavailable in v1.22+; use networking.k8s.io/v1 Ingress
W0125 21:02:19.816583       8 warnings.go:67] networking.k8s.io/v1beta1 Ingress is deprecated in v1.19+, unavailable in v1.22+; use networking.k8s.io/v1 Ingress
192.168.49.1 - - [25/Jan/2021:21:04:50 +0000] "POST /api/v1/user/new HTTP/1.1" 302 301 "http://mylocalhost.info/user/new" "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/87.0.4280.141 Safari/537.36" 673 0.002 [default-backend-default-8080] [] 172.17.0.9:8080 301 0.000 302 88b814fc0fadce0cfd62358c64b2fcd9
192.168.49.1 - - [25/Jan/2021:21:04:50 +0000] "GET /api/v1/user/new HTTP/2.0" 500 22 "http://mylocalhost.info/user/new" "Mozilla/5.0

请注意，/user/new 端点是前端所命中的。你可以看到有 302 响应。

【问题讨论】：

你能列出你的服务和部署清单吗？
当然我现在已经添加了。
谢谢。如何判断请求 HTTP 方法从 GET 更改为 POST？
我怀疑这是问题所在，因为如果我在我的 chrome 浏览器上检查网络，我首先会看到 302 重定向（我假设这是来自 Ingress），而下一个请求是完全相同的URL 但它现在有一个 POST 方法。此外，如果我在没有 kubernetes 的情况下使用该应用程序，则在执行 API 调用时看不到任何重定向。
您应该能够在 Ingress 日志中看到所有请求。

标签： nginx kubernetes kubernetes-ingress minikube

【解决方案1】：

前端应该通过后端 Service 而不是 Ingress 访问后端。它们默认位于相同的命名空间中，因此您只能通过服务 DNS 名称相互访问。前端 pod 可以通过 http://backend-default:8080/ 或通过 DNS http://backend-default.default.cluster.local:8080 访问后端服务

参考： DNS for Services and Pods

【讨论】：