Cannot find module '/root/tileserver/node_modules/mapnik/lib/binding/mapnik_settings.js'

[Joseph Simon]

i wanna make the tile service environment succeed,but i have gotten some problems during the procedure.Here is the trouble that calls:
Error: Cannot find module '/root/tileserver/node_modules/mapnik/lib/binding/mapnik_settings.js'
at Function.Module._resolveFilename (module.js:469:15)
at Function.Module._load (module.js:417:25)
at Module.require (module.js:497:17)
at require (internal/module.js:20:19)
at Object. (/root/tileserver/node_modules/mapnik/lib/mapnik.js:8:16)
at Module._compile (module.js:570:32)
at Object.Module._extensions..js (module.js:579:10)
at Module.load (module.js:487:32)
at tryModuleLoad (module.js:446:12)
at Function.Module._load (module.js:438:3)

I am a novice,and learn by a blog called [#link# http://www.cnblogs.com/think8848/p/6262696.html].
As a learner,i urge to get the problem and understand it.
Help me,please.

problem:
http://ww3.sinaimg.cn/large/0060lm7Tly1fp5qn3bub5j30js064mx1.jpg

package.json
http://ww4.sinaimg.cn/large/0060lm7Tly1fp5qol4n58j30et0b9gli.jpg