diff --git a/prod/upload/upload.lua b/prod/upload/upload.lua
index 7ff1fc2..b6f176b 100644
--- a/prod/upload/upload.lua
+++ b/prod/upload/upload.lua
@@ -28,11 +28,11 @@ while true do
         local val = res[2]
         if key == "Content-Type" then
             local ext = ngx.re.match(val, [[(\w+)\/(\w+)]], "jo")[2]
-            file_name = string.format("%s/%s.%s", file_dir, uuid(), ext)
+            file_name = uuid() .. "." .. ext
         end
 
         if file_name then
-            file = io.open(file_name, "w+")
+            file = io.open(file_dir .. "/" .. file_name, "w+")
             if not file then
                 ngx.say("failed to open file ", file_name)
                 return
@@ -50,6 +50,8 @@ while true do
             file:close()
             table.insert(files, file_name)
         end
+        -- 这里要重置一下file_name，否则后面的文件保存时会导致前面已保存的文件变成空文件
+        file_name = nil
         file = nil
     elseif typ == "eof" then
         local http = require "resty.http"