optimize _BASE.db_read()

nginx/lua/base.lua

 local _BASE = {}
 
-
 local json = require ('cjson')
+
 function _BASE.print_log(fname, ...)
   local f = io.open(string.format("/Users/zhoush/openresty/nginx/logs/%s_%s.log", fname, os.date("%Y%m%d")), "a+")
   local str = ""
@@ -15,15 +15,14 @@ function _BASE.print_log(fname, ...)
   f:close()
 end
 
-function _BASE.db_read()
-  local f = io.open("/Users/zhoush/openresty/nginx/conf/dbs.json", "r")
+function _BASE.db_read(dbpath)
+  local f = io.open("/Users/zhoush/openresty/nginx/conf/"..dbpath, "r")
   local tmp = f:read("a*")
   local db_st = json.decode(tmp)
   f:close()
   return db_st
 end
 
-
 function _BASE.close_db(db)
   if not db then
     return