How to insert a Ruby on Rails page into another site using an IFRAME?

Question

Ruby on Rails

Good afternoon.
Thought it would be much easier.
A Ruby on Rail application creates a page with a specific post.
I thought I could paste it on another site with a regular iframe like:

<iframe width="100%" height="580" src="http://railsapp.com/posts/4" frameborder="0" allowfullscreen></iframe>

As a result, I get an empty page:

Please, tell me the solution.
I googled, but something does not give out. Or I'm wording it wrong.

Answer 1

https://stackoverflow.com/questions/16561066/ruby-...
If it helped the author, then let it be as an answer, maybe someone will come in handy