使用nginx解决k8s traefik中basic auth的跨域问题

目地

目前k8s ingress是配合traefik使用的，此时需要对某一个域名添加一个basic auth安全认证，原本traefik也可以正常配置（生产环境已有不少使用traefik basic auth），但是由于此处的域名需要在其他web域中调用，涉及到跨域问题，参考traefik文档未发现在k8s有关联说明解决basic auth相关跨域问题。后来分析了下nginx下的basic auth,最终使用nginx + ingress + traefik解决了这一问题。

简要步骤

1. 生成basic auth用户密码文件 htpasswd -bc ngauth username password

2. 配置nginx的k8s configMap:

   kind: ConfigMap
   apiVersion: v1
   metadata:
   name: nginx-conf
   namespace: kube-apps
   data:
   nginx.conf: |
   user  nginx;
   worker_processes  1;
   
   
   error_log  /var/log/nginx/error.log warn;
   pid        /var/run/nginx.pid;
   
   
   events {
       worker_connections  1024;
   }
   
   
   http {
       default_type  application/octet-stream;
   
   
       log_format  main  '$remote_addr - $remote_user [$time_local] "$request" '
                         '$status $body_bytes_sent "$http_referer" '
                         '"$http_user_agent" "$http_x_forwarded_for"';
   
   
       access_log  /var/log/nginx/access.log  main;
   
   
       sendfile        on;
       #tcp_nopush     on;
   
   
       keepalive_timeout  65;
   
   
       #gzip  on;
   
   
       upstream monitors {
           server monitoring-system-service.kube-apps:8080;
       }
   
   
       server {
           listen 80;
           auth_basic           "closed site";
           auth_basic_user_file ngauth;
           location / {
             if ($request_method = OPTIONS ) {
               add_header Access-Control-Allow-Origin "null"; # <- needs to be updated
               add_header Access-Control-Allow-Methods "GET, OPTIONS";
               add_header Access-Control-Allow-Headers "Authorization";   # <- You may not need this...it's for Basic Auth
               add_header Access-Control-Allow-Credentials "true";        # <- Basic Auth stuff, again
               add_header Content-Length 0;
               add_header Content-Type text/plain;
               return 200;
             }
             proxy_pass http://monitors;
           }
       }
   }
   ngauth: |
   username:password
   

   注意:ngauth 下面的username和password需要替换为步骤1中生成文件的用户名和密码

3. 建议在本地先使用docker进行调试，如果没有问题，则可以进行下一步，部署到k8s中 “` docker run –name nginx-container -v /home/user/nginx/:/etc/nginx/nginx.conf:ro -d nginx:1.12.2

4. 部署到k8s
nginx.yaml如下：
    ```
        apiVersion: v1
        kind: Service
        metadata:
          name: nginx
          labels:
            app: nginx
          namespace: kube-apps
        spec:
          type: NodePort
          selector:
            app: nginx
          ports:
          - name: http
            port: 80
            targetPort: 80
        \---
        apiVersion: extensions/v1beta1
        kind: Deployment
        metadata:
          name: nginx
          namespace: kube-apps
          labels:
            addonmanager.kubernetes.io/mode: Reconcile
        spec:
          template:
            metadata:
              labels:
                app: nginx
            spec:
              containers:
              - name: nginx
                image: nginx:1.12.2
                ports:
                - containerPort: 80
                volumeMounts:
                - name: config-volume
                  mountPath: /etc/nginx/
              volumes:
              - name: config-volume
                configMap:
                  name: nginx-conf
                  items:
                  - key: nginx.conf
                    path: nginx.conf
                  - key: ngauth
                    path: ngauth
    ```
执行：

$ kubectl create -f configMap.yaml $ kubectl create -f nginx.yaml “` 5. 配置traefik指向地址为nginx的service地址即可

参考

http://nginx.org/en/docs/http/ngx_http_auth_basic_module.html