lua-resty-upstream-healthcheck使用

• health.txt 在每个upstream 服务器组的root 目录下创建这个文件，目录结构如下所示

  ├── html
  │   ├── 50x.html
  │   ├── index.html
  │   ├── websocket001.html
  │   └── websocket02.html
  ├── html81
  │   ├── 50x.html
  │   ├── health.txt
  │   └── index.html
  ├── html82
  │   ├── 50x.html
  │   ├── health.txt
  │   └── index.html
  ├── html83
  │   ├── 50x.html
  │   ├── health.txt
  │   └── index.html
  ├── html84
  │   ├── 50x.html
  │   └── index.html
• nginx.conf

  worker_processes  8;
  
  error_log  logs/error.log;
  pid        logs/nginx.pid;
  
  events {
      use epoll;
      worker_connections  1024;
  }
  
  http {
      include       mime.types;
      default_type  text/html;
      #lua模块路径，其中”;;”表示默认搜索路径，默认到/usr/servers/nginx下找  
      lua_package_path "/home/tinywan/Openresty_Protect/First_Protect/lualib/?.lua;;";  #lua 模块  
      lua_package_cpath "/home/tinywan/Openresty_Protect/First_Protect/lualib/?.so;;";  #c模块  
      include /home/tinywan/Openresty_Protect/First_Protect/nginx_first.conf;
  }
  
• nginx_first.conf

  upstream tomcat {
      server 127.0.0.1:8081;
      server 127.0.0.1:8082;
      server 127.0.0.1:8083;
      server 127.0.0.1:8084 backup;
  }
  
  lua_shared_dict healthcheck 1m;
  
  lua_socket_log_errors off;
  
  init_worker_by_lua_block {
      local hc = require "resty.upstream.healthcheck"
      local ok, err = hc.spawn_checker{
              shm = "healthcheck",  -- defined by "lua_shared_dict"
              upstream = "tomcat", -- defined by "upstream"
              type = "http",
  
              http_req = "GET /health.txt HTTP/1.0\r\nHost: tomcat\r\n\r\n",
                      -- raw HTTP request for checking
  
              interval = 2000,  -- run the check cycle every 2 sec
              timeout = 1000,   -- 1 sec is the timeout for network operations
              fall = 3,  -- # of successive failures before turning a peer down
              rise = 2,  -- # of successive successes before turning a peer up
              valid_statuses = {200, 302},  -- a list valid HTTP status code
              concurrency = 10,  -- concurrency level for test requests
          }
  }
  
  server {
      listen       80;
      server_name  localhost;
      
      location / {
          proxy_pass          http://tomcat;
       }
  
      location /server/status {
          access_log off;
          allow 127.0.0.1;
  
          default_type text/plain;
          content_by_lua_block {
              local hc = require "resty.upstream.healthcheck"
              ngx.say("Nginx Worker PID: ", ngx.worker.pid())
              ngx.print(hc.status_page())
          }
      }
  }
  
  server {
      listen       8081;
      server_name  localhost;
  
      location / {
          root   html81;
          index  index.html index.htm;
      }
  
      location /health_status {
  
      }
  }
  
  server {
      listen       8082;
      server_name  localhost;
  
      location / {
          root   html82;
          index  index.html index.htm;
      }
  
      location /health_status {
  
      }
  }
  
  server {
      listen       8083;
      server_name  localhost;
  
      location / {
          root   html83;
          index  index.html index.htm;
      }
  
      location /health_status {
  
      }
  }
  
  server {
      listen       8084;
      server_name  localhost;
  
      location / {
          root   html84;
          index  index.html index.htm;
      }
  }
  
• 状态查看,通过访问:http://127.0.0.1/server/status