kubernetes ingress更改日志格式

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　Ingress Nginx默认访问日志都输出到/var/log/nginx/access.log文件中，但是对于一般的生产环境来说，不可能把所有日志都输到一个日志文件中，一般情况都是根据域名分别输出到各个文件中。所以这里区分http指令域默认配置以及单独域名的日志的配置方式。

1.默认日志格式更改为json

　　修改mandatory.yaml部署文件nginx-configuration ConfigMap配置中log-format-upstream字段，具体修改如下:

  log-format-upstream: '{"time": "$time_iso8601", "remote_addr": "$proxy_protocol_addr",
    "x-forward-for": "$proxy_add_x_forwarded_for", "request_id": "$req_id", "remote_user":
    "$remote_user", "bytes_sent": $bytes_sent, "request_time": $request_time, "status":$status,
    "vhost": "$host", "request_proto": "$server_protocol", "path": "$uri", "request_query":
    "$args", "request_length": $request_length, "duration": $request_time,"method":
    "$request_method", "http_referrer": "$http_referer", "http_user_agent": "$http_user_agent"}'

第二种：
  log-format-upstream: '{"nginx_timestamp":"$time_iso8601","clientip":"$remote_addr","nginx_host":"$server_addr","host":"$http_host","request":"$request","url":"$request_uri","upstreamhost":"$upstream_addr","status":"$status","body_bytes_sent":"$body_bytes_sent","request_time":"$request_time","upstream_response_time":"$upstream_response_time","xff":"$http_x_forwarded_for","referer":"$http_referer","http_user_agent":"$http_user_agent","request_length":"$request_length","request_method":"$request_method"}'

　　注意：mandatory.yaml是官方ingress-nginx的默认安装yaml文件,其中也有configmap的配置,这是配置为空，留给运维人员自定义发挥。这里只是截出configmap的配置。（安装ingress这里不做演示，参考本人ingress安装博客）

kind: ConfigMap
apiVersion: v1
metadata:
  name: nginx-configuration
  namespace: ingress-nginx
  labels:
    app.kubernetes.io/name: ingress-nginx
    app.kubernetes.io/part-of: ingress-nginx
data:
  log-format-upstream: '{"nginx_timestamp":"$time_iso8601","clientip":"$remote_addr","nginx_host":"$server_addr","host":"$http_host","request":"$request","url":"$request_uri","upstreamhost":"$upstream_addr","status":"$status","body_bytes_sent":"$body_bytes_sent","request_time":"$request_time","upstream_response_time":"$upstream_response_time","xff":"$http_x_forwarded_for","referer":"$http_referer","http_user_agent":"$http_user_agent","request_length":"$request_length","request_method":"$request_method"}'

　　部署了上述文件后，查看一下ingress-nginx的配置文件中发生了什么变化

#先将nginx配置文件拷贝出来比较容易查看
kubectl  cp -n ingress-nginx  nginx-ingress-controller-8f68db9b5-2flsq:/etc/nginx/nginx.conf /test/nginx.conf
#找到文件变化的配置文件

　　目前ingress-nginx配置日志文件格式为json输出已经完成了。一般默认中server指令域中如果不配置单独的日志输出，会使用http中默认的日志配置。如果需要为每一个域名独立配置文件，见如下。

2.根据域名配置访问日志输出

　　这里使用一个测试网站的ingress的yaml文件来作为演示。

cat gcc-21ldj-frontend-ingress.yaml 
---
apiVersion: extensions/v1beta1
kind: Ingress
metadata:
  name: gcc-21ldj-frontend
  namespace: dev
  annotations:
    kubernetes.io/ingress.class: nginx
    nginx.ingress.kubernetes.io/configuration-snippet: |
      access_log /var/log/nginx/gcc-h5-test01.access.log upstreaminfo if=$loggable;
      # 这里直接引用了http指令域的upstreaminfo。
      error_log  /var/log/nginx/gcc-h5-test01.error.log;
      rewrite /gcc/21ldj/(.*) /$1 break;
spec:
  tls:
    - hosts:
        - gcc-h5-test01.mbgadev.cn
      secretName: mbgadev-20210908
  rules:
    - host:  gcc-h5-test01.mbgadev.cn
      http:
        paths:
          - path: /gcc/21ldj/
            backend:
              serviceName: gcc-21ldj-frontend
              servicePort: 80

　　部署该ingress文件后，查看一下nginx文件的变化。

#将最新的nginx文件拷贝一下 
kubectl  cp -n ingress-nginx  nginx-ingress-controller-8f68db9b5-2flsq:/etc/nginx/nginx.conf /test/nginx.conf
#找到文件变化的配置文件

　　注：if=$loggable的含义

#参数 if，设置是否记录日志，当参数值的条件成立，即不为 0 或空时，才记录日志。
下面是ingress-nginx中的配置文件
map $status $loggable {
    ~^[23]  0;
    default 1;
}

access_log logs/access.log combined if=$loggable;
具体可参考：Nginx日志管理

3.参考

Log format – ingress-nginx-docs-cn

　　Ingress配置参考：https://github.com/kubernetes/ingress-nginx/blob/master/docs/user-guide/nginx-configuration/configmap.md

　　Ingress注释参考https://github.com/kubernetes/ingress-nginx/blob/master/docs/user-guide/nginx-configuration/annotations.md