what is InvalidAuthenticityToken?

I create a ruby script to submit a post to my local rails application,
but doesn't return a data. so I open a log file, saw this.

http://guides.rubyonrails.org/security.html#cross-site-request-forgery-csrf

You can use:

http://apidock.com/rails/ActionController/RequestForgeryProtection/form_authenticity_token

To get the value (or use form_for, which automatically handles it).

Cheers,

Andy