lua_memcached_mysql_www.conf

        location /video {
            index index.html index.htm index.php
            add_header Content-Type "text/plain text/html charset=utf-8" ;
            set $oldurl  "";
            set $newurl  "";
            rewrite_by_lua '
                local aurl = "http://"..ngx.var.server_name..ngx.var.request_uri
                local access_url = "http://"..ngx.var.server_addr..ngx.var.request_uri
                local memcached = require "resty.memcached"
                local memc, err = memcached:new()
                if not memc then
                    ngx.say("failed to instantiate memc")
                    return
                end

                memc:set_timeout(1000) -- 1 sec

                local ok, err = memc:connect("192.168.xxx.xxx", 11211)
                if not ok then
                    ngx.say("failed to connect")
                    -- return
                end

                local un_access_url  = ngx.unescape_uri(access_url)
                local res, flags, err = memc:get(un_access_url)
                if err then
                    ngx.say("failed to get url")
                end

                if not res then

                    local mysql = require "resty.mysql"
                    local db, err = mysql:new()
                    if not db then
                        return ngx.exit(404)
                    end
                    db:set_timeout(1000) -- 1 sec

                    local ok, err, errno, sqlstate = db:connect{
                        host = "192.168.xxx.xxx",
                        port = 3306,
                        database = "xxxx",
                        user = "xxxx",
                        password = "xxxx",
                        max_packet_size = 1024 * 1024
                    }

                    if not ok then
                        return ngx.exit(404)
                    end

                    local un_aurl  = ngx.unescape_uri(aurl)
                    local sql_name = ngx.quote_sql_str(un_aurl)
                    local sql = "select old_url,new_url from group_plugin_fansclub_old_article_log where old_url = " .. sql_name
                    res, err, errno, sqlstate = db:query(sql)
                    if not res then
                        return ngx.exit(404)
                    end
                    for key,value in pairs(res)do
                        newurl = value.new_url
                        oldurl = value.old_url
                    end
                    if oldurl then
                        local ok, err = memc:set(oldurl,newurl)
                        return ngx.redirect(newurl,301)
                    else
                        ngx.exit(404)
                    end
                end
                local ok, err = memc:set_keepalive(10000, 100)
                if not ok then
                    ngx.say("cannot set keepalive: ", err)
                    return
                end
                -- ngx.say("memcached url")
                ngx.redirect(res,301)
                return


           ';
        }