How to secure a published site on the Internet?

Question

Ruby on Rails

Hello. There is a written application in Ruby on rails. I'm going to transfer it to hosting, in connection with this I have a question, how about security? What would you recommend to read on this topic? What do you do when you publish your application?

Answer 1

Question from the category "How to protect yourself when you go out?" :)
Protect from what:
Need more specifics. And so a good guide to start rusrails.ru/ruby-on-rails-security-guide

Answer 2

Nothing when posting.
It was necessary to do something earlier, when writing.
The most common errors are incorrectly specifying fields for bulk assignment, and not checking access to the resource (especially for modification) for the current user.