nginx lua读redis

• 国内企业使用nginx的还是挺多的，我在工作的过程中，也经常使用nginx；下面就简单记录一下lua访问redis

  local cjson = require "cjson"
  local redis = require "resty.redis"
  local red = redis:new()  
  
  -- 设置后续操作的超时（以毫秒为单位）保护，包括connect方法
  red:set_timeout(60000) 
  -- 连接redis;两个参数分别是IP以及端口号
  local ok, err = red:connect("xxx.xxx.xxx.xxx", 6379) 
  if not ok then
      return
  end
  -- 设置连接密码
  red:auth("xxxx")
  -- 切换数据库，不设置，默认是0库
  red:select(1)
  
  local json_results={}
  
  local request_method = ngx.var.request_method
  if request_method == "GET" then
      json_results["userTag"] = 0
      local value = cjson.encode(json_results)
      ngx.say(value) 
      return
  elseif request_method == "POST" then
      ngx.req.read_body()
      args= ngx.req.get_body_data()
  end
  
  local arg=cjson.decode(args)
  
  if (type(arg["userIdList"]) == "nil") or (arg["userIdList"] == "") then 
      json_results["userTag"] = 0
      local value = cjson.encode(json_results)
      ngx.say(value) 
      return
  end
  
  local useridList = {}
  -- 设置为pipeline()模式；批量获取value
  red:init_pipeline()
  for k,userid in pairs(arg["userIdList"]) do
      useridList[k] = userid
      red:get("userTest_"..userid)
  end
  -- 提交所有的key
  local respTable, err = red:commit_pipeline()  
  
  -- local res, err = red:get(userid) 或者这种一次获得一个key
  
  if (not respTable) or  respTable == ngx.null then
      json_results["userTag"] = 0
      local value = cjson.encode(json_results)
      ngx.say(value) 
      return
  end
  
  local i = 0
  local res_userid={}
  -- 对有值的key的处理
  for k, v in pairs(respTable) do  
       if v ~= ngx.null then 
          res_userid[#res_userid+1] = cjson.decode(v)
          table.remove(useridList,k-i)
          i = i + 1
       end
  end 
  -- 对无值的key的处理
  for k,userid in pairs(useridList) do
      local k_v={}
      k_v["error_code"] = 101
      k_v["userid"] = userid
      res_userid[#res_userid+1] = k_v
  end
  
  json_results["userTag"] = res_userid
  local value = cjson.encode(json_results)
  ngx.say(value) 
  red:close()