SunPanel报错：attempt to index local 'obj' (a nil value)

故障现象

通过istore安装SunPanel，安装过程正常，但无法打开网页，并出现如下lua报错：

Runtime error
Unhandled exception during request dispatching
/usr/lib/lua/luci/ucodebridge.lua:23: /usr/lib/lua/luci/model/sunpanel.lua:13: attempt to index local 'obj' (a nil value)

In error(), file [C]
called from function [anonymous function] (/usr/lib/lua/luci/ucodebridge.lua:23)
called from function ((tail call))
In [anonymous function](), file /usr/share/ucode/luci/runtime.uc, line 148, byte 45:
  called from function [arrow function] (/usr/share/ucode/luci/dispatcher.uc:794:4)
  called from function render ([C])
  called from function render_action (/usr/share/ucode/luci/dispatcher.uc:768:24)
  called from function run_action (/usr/share/ucode/luci/dispatcher.uc:795:4)
  called from function [anonymous function] (/usr/share/ucode/luci/dispatcher.uc:1003:48)
  called from anonymous function (/www/cgi-bin/luci:39:13)

 `        return lcall.call(modname, method, ...args);`
  Near here ----------------------------------------^

分析并解决

经查/usr/lib/lua/luci/model/sunpanel.lua发现，导致该问题的核心源于是lsblk未返回正确结果。我所使用的系统并不自带lsblk命令，而且即使通过opkg安装也无法正常使用。

进一步读源码后认为该信息并不关键，故更改源码，从第6行起的sunpanel.blocks函数，直接返回空数组。

sunpanel.blocks = function()
  --[[
  local f = io.popen("lsblk -s -f -b -o NAME,FSSIZE,MOUNTPOINT --json", "r")
  local vals = {}
  if f then
    local ret = f:read("*all")
    f:close()
    local obj = jsonc.parse(ret)
    for _, val in pairs(obj["blockdevices"]) do
      local fsize = val["fssize"]
      if fsize ~= nil and string.len(fsize) > 10 and val["mountpoint"] then
        -- fsize > 1G
        vals[#vals+1] = val["mountpoint"]
      end
    end
  end
  return vals
  ]]--
  return {}
end

保存后刷新网页，即可正常使用。可手动指定配置文件路径为/etc/config/SunPanel。