refactor some lua code

rootfs/etc/nginx/lua/util.lua

@@ -49,17 +49,6 @@ function _M.lua_ngx_var(ngx_var)
   return ngx.var[var_name]
 end
 
-function _M.split_pair(pair, seperator)
-  local i = pair:find(seperator)
-  if i == nil then
-    return pair, nil
-  else
-    local name = pair:sub(1, i - 1)
-    local value = pair:sub(i + 1, -1)
-    return name, value
-  end
-end
-
 -- this implementation is taken from
 -- https://web.archive.org/web/20131225070434/http://snippets.luacode.org/snippets/Deep_Comparison_of_Two_Values_3
 -- and modified for use in this project
@@ -88,30 +77,6 @@ function _M.is_blank(str)
   return str == nil or string_len(str) == 0
 end
 
--- http://nginx.org/en/docs/http/ngx_http_upstream_module.html#example
--- CAVEAT: nginx is giving out : instead of , so the docs are wrong
--- 127.0.0.1:26157 : 127.0.0.1:26157 , ngx.var.upstream_addr
--- 200 : 200 , ngx.var.upstream_status
--- 0.00 : 0.00, ngx.var.upstream_response_time
-function _M.split_upstream_var(var)
-  if not var then
-    return nil, nil
-  end
-  local t = {}
-  for v in var:gmatch("[^%s|,]+") do
-    if v ~= ":" then
-      t[#t+1] = v
-    end
-  end
-  return t
-end
-
-function _M.get_first_value(var)
-  local t = _M.split_upstream_var(var) or {}
-  if #t == 0 then return nil end
-  return t[1]
-end
-
 -- this implementation is taken from:
 -- https://github.com/luafun/luafun/blob/master/fun.lua#L33
 -- SHA: 04c99f9c393e54a604adde4b25b794f48104e0d0