回答

local function close_redis(red) 
if not red then 
return 
end 
local ok, err = red:close() 
if not ok then 
ngx.say("close redis error : ", err) 
end 
end 

local redis = require("resty.redis") 

--创建实例 
local red = redis:new() 
--设置超时（毫秒） 
red:set_timeout(1000) 
--建立连接 
local ip = "127.0.0.1" 
local port = 6379 
local ok, err = red:connect(ip, port) 
if not ok then 
ngx.say("connect to redis error : ", err) 
return close_redis(red) 
end 

local res, err = red:auth("shiyuesoft")
if not res then
ngx.say("failed to authenticate: ", err)
return
end


--调用API进行处理 
ok, err = red:set("msg", "hello world") 
if not ok then 
ngx.say("set msg error : ", err) 
return close_redis(red) 
end 

--调用API获取数据 
local resp, err = red:get("msg") 
if not resp then 
ngx.say("get msg error : ", err) 
return close_redis(red) 
end 
--得到的数据为空处理 
if resp == ngx.null then 
resp = '' --比如默认值 
end 
ngx.say("msg : ", resp) 

close_redis(red)