I am currently working on that at the moment. I can't share the workbook yet but I will ask my manager to know if I can share it with the Tableau community.
My work is mainly based on this blog post: Tableau Zen: Custom Tableau Server Admin Views
You might find interesting information there.
All I do is basically to adapt this views to my Tableau Server environment with multiple sites.
Thanks Damien for your reply ,I am hoping someone will reply with some developed workbook or may be idea how to develop this,I am not very good on development though.