CKeditor file path or url issue on server

This error is in all cases that CKEDITOR.getUrl() is called. Most notably the language file that CKEditor grabs first is from the wrong resource URL. In this case

Error can be like that :
GET http://localhost:3000/assets/admin/skins/moono/editor.css?t=EAPE  ckeditor.js?body=1:78
GET http://localhost:3000/assets/admin/lang/en.js?t=EAPE  ckeditor.js?body=1:78
Uncaught TypeError: Cannot set property 'dir' of undefined ckeditor.js?body=1:221

You can solve that using that javascript

<script>
 window.CKEDITOR_BASEPATH="//localhost:3000/ckeditor/4.0.1.1/ckeditor/"
</script>