local function close_redis(red)  if not red then  returnend --释放连接(连接池实现)  local pool_max_idle_time = 10000 --毫秒  local pool_size = 100 --连接池大小  local ok, err = red:set_keepalive(pool_max_idle_time, pool_size)  if not ok then  ngx.say("set keepalive error : ", err)  end
endlocal function errlog(...)ngx.log(ngx.ERR, "redis: ", ...)
endlocal redis = require "resty.redis"  --引入redis模块
local red = redis:new()  --创建一个对象，注意是用冒号调用的--设置超时（毫秒）
red:set_timeout(1000)
--建立连接
local ip = "10.11.0.215"
local port = 6379
local ok, err = red:connect(ip, port)
if not ok then  close_redis(red)errlog("Cannot connect");return ngx.exit(ngx.HTTP_INTERNAL_SERVER_ERROR)
end  local key = "limit:frequency:login:"..ngx.var.remote_addr--得到此客户端IP的频次
local resp, err = red:get(key)
if not resp then  close_redis(red)return ngx.exit(ngx.HTTP_INTERNAL_SERVER_ERROR) --redis 获取值失败
end if resp == ngx.null then   red:set(key, 1) -- 单位时间 第一次访问red:expire(key, 10) --10秒时间 过期
end  if type(resp) == "string" then if tonumber(resp) > 10 then -- 超过10次
        close_redis(red)return ngx.exit(ngx.HTTP_FORBIDDEN) --直接返回403end
end--调用API设置key
ok, err = red:incr(key)
if not ok then  close_redis(red)return ngx.exit(ngx.HTTP_INTERNAL_SERVER_ERROR) --redis 报错
end  close_redis(red)  

# vim /usr/local/lua/access_by_limit_frequency.lualocal function close_redis(red)if not red thenreturnendlocal pool_max_idle_time = 10000local pool_size = 100local ok, err = red:set_keepalive(pool_max_idle_tme, pool_size)if not ok thenngx.say("set keepalive err : ", err)end
endlocal function errlog(...)ngx.log(ngx.ERR, "redis: ", ...)
endlocal redis = require "resty.redis"
local red = redis:new()red:set_timeout(1000)
local ip = "10.11.0.215"
local port = 6379
local ok,err = red:connect(ip, port)
if not ok thenclose_redis(red)errlog("connot connect");return ngx.exit(ngx.HTTP_INTERNAL_SERVER_ERROR)
endlocal count, err = red:get_reused_times()
if 0 == count then ----新建连接，需要认证密码ok, err = red:auth("redis123")if not ok thenngx.say("failed to auth: ", err)returnend
elseif err then  ----从连接池中获取连接，无需再次认证密码ngx.say("failed to get reused times: ", err)return
endlocal key = "limit:frequency:login: " ..ngx.var.remote_addr--得到此客户端IP的频次
local resp,err = red:get(key)
if not resp thenclose_redis(red)return ngx.exit(ngx.HTTP_INTERNAL_SERVER_ERROR)
endif resp == ngx.null thenred:set(key, 1)red:expire(key, 100) -- 设置过期时间，即返回403的时间为100秒
end--ngx.say("connect ok")
--ngx.say("resp:",resp)
if type(resp) == "string" thenif tonumber(resp) > 10 thenclose_redis(red)return ngx.exit(ngx.HTTP_FORBIDDEN)end
endok, err = red:incr(key)
if not ok thenclose_redis(red)return ngx.exit(ngx.HTTP_INTERNAL_SERVER_ERROR)
endclose_redis(red)