openresty+lua 动态更新upstram里的server （下）lua实现动态更新upstream

分手后的思念是犯贱 2022-05-25 03:19 329阅读 0赞

**如果基础环境没有配置的话，请到上篇，https://blog.csdn.net/u014686399/article/details/80225843**

**步骤一：更新自带的lualib/resty/upstream/healthcheck.lua**

（1）备份一下lualib/resty/upstream/healthcheck.lua

（2）在合适的地方添加一个函数，一定要在return \_M之前

--judge user_define
    local function match_user_define(host,port)
            local user_define,message=get_user_define()
            local stop_sign=false
            local server=host..':'..port
            if not user_define then
                    error(message)
            else
                 local value, flags=user_define:get(server)
                 if value == 0 then
                    stop_sign=true
                 end
            end
            return stop_sign
    end
    --end user define

（3）修改check\_peer函数，如下

--[[if peer.host then
            -- print("peer port: ", peer.port)
            ok, err = sock:connect(peer.host, peer.port)
        else
            ok, err = sock:connect(name)
        end--]]
        mathch_result=match_user_define(peer.host, peer.port)
        if not mathch_result  then
            if peer.host then
                    -- print("peer port: ", peer.port)
                    ok, err = sock:connect(peer.host, peer.port)
            else
                    ok, err = sock:connect(name)
            end
        else
            ok=nil
            peer.down=false
            err=" The user defines the state of the host to stop"
        end

（4）修改openresty的http模块，添加下面参数

lua_shared_dict user_define 1m;

（5）重启openresty，看一下errlog是不是有报错，有报错是不正常的

**步骤二**

（1）在lualib下创建upstream\_update.lua

local _M = { _VERSION = '1.0' }
    local function split( str,reps )
        local resultStrList = {}
        string.gsub(str,'[^'..reps..']+',function ( w )
            table.insert(resultStrList,w)
        end)
        return resultStrList
    end
    
    local function get_user_define()
        local user_define=ngx.shared['user_define']
        if not user_define then
        	return nil, "share memory variable[user_define] not found"
    		else
          return user_define, ""
    		end
    end
    
    --add server to user_define
    local function common_user_define(func_name)
    	 user_define,message=get_user_define()
    	 if not user_define then
    	 	   ngx.say("failed to get share memory variable [user_define]: ", message)
           return
    	 end
    	 ngx.req.read_body()
    	 local args, err = ngx.req.get_post_args()
       if err == "truncated" then
           -- one can choose to ignore or reject the current request here
       end
       if not args['server'] then
           ngx.say("failed to get post args: ", err)
           return
       else
    		  if type(args['server']) ~= 'table' then
    		 	server_list=split(args['server'],',')
    		 else
    			server_list=args['server']
    		 end
    		 func_name(server_list,user_define)
       end
    end
    
    local function add_user_func(server_list,user_define)
    		 for _,value in ipairs(server_list) do
     		 			--table.insert(user_define,value)
              				succ, err, forcible=user_define:set(value, 0)
    					if not succ then
    					    ngx.say("failed to set share memory variable [user_define]", err)
    					    return nil
    					end
    		end
                    local temp_list=user_define:get_keys()
     		ngx.say("OK,all server: ", table.concat(temp_list,", "))
    		return user_define
    end
    
    function _M.add_user_define()
    		common_user_define(add_user_func)
    end
    --del server to user_define
    local function del_user_func(server_list,user_define)
    	     for _,value in ipairs(server_list) do
    	 	     	succ, err, forcible=user_define:delete(value)
              if not succ then
                        ngx.say("failed to set share memory variable [user_define]", err)
                        break
               end
           end
           local temp_list=user_define:get_keys()
           ngx.say("OK,all server: ", table.concat(temp_list,", "))
    end
    
    function _M.del_user_define()
    		common_user_define(del_user_func)
    end
    
    return _M
    		 	server_list=split(args['server'],',')
    		 else
    			server_list=args['server']
    		 end
    		 func_name(server_list,user_define)
       end
    end
    
    local function add_user_func(server_list,user_define)
    		 for _,value in ipairs(server_list) do
     		 			--table.insert(user_define,value)
              				succ, err, forcible=user_define:set(value, 0)
    					if not succ then
    					    ngx.say("failed to set share memory variable [user_define]", err)
    					    return nil
    					end
    		end
                    local temp_list=user_define:get_keys()
     		ngx.say("OK,all server: ", table.concat(temp_list,", "))
    		return user_define
    end
    
    function _M.add_user_define()
    		common_user_define(add_user_func)
    end
    --del server to user_define
    local function del_user_func(server_list,user_define)
    	     for _,value in ipairs(server_list) do
    	 	     	succ, err, forcible=user_define:delete(value)
              if not succ then
                        ngx.say("failed to set share memory variable [user_define]", err)
                        break
               end
           end
           local temp_list=user_define:get_keys()
           ngx.say("OK,all server: ", table.concat(temp_list,", "))
    end
    
    function _M.del_user_define()
    		common_user_define(del_user_func)
    end
    
    return _M

(2)修改nginx.conf的server模块

location /add_user_define {
             content_by_lua '
                    local  user_fun = require "upstream_update"
                    user_fun.add_user_define()
                ';
                                  }
        location /del_user_define {
             content_by_lua '
                    local  user_fun = require "upstream_update"
                    user_fun.del_user_define()
                ';
                                  }

（3）重启一下openresty，看一下errlog，不出现报错是正常的状态

**步骤三：测试**

（1）访问http://192.168.0.17:8000//index.html，连续两次应该能发现，会转发到192.168.0.16和192.168.0.17

(2)curl -X POST -d "server=192.168.0.16:80&server=192.168.0.17:80" http://192.168.0.17:8000/add\_user\_define 去掉所有的server，然后再访问http://192.168.0.17:8000//index.html，会得到

errlog：

![20180507155017725][]

页面：

![20180507155103680][]

（3）curl -X POST -d "server=192.168.0.16:80" http://192.168.0.17:8000/del\_user\_define，放开192.168.0.16，然后访问http://192.168.0.17:8000//index.html，会得到192.168.0.16的页面  
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[20180507155017725]: /images/20220525/81cbae146a8c4bccb3a17da2dff22f6b.png
[20180507155103680]: /images/20220525/4d2e4c18d0304a3691d6f728b9687b2d.png