Using helpers in model: how do I include helper dependencies?

Question

I'm writing a model that handles user input from a text area. Following the advice from http://blog.caboo.se/articles/2008/8/25/sanitize-your-users-html-input, I'm cleaning up the input in the model before saving to database, using the before_validate callback.

The relevant parts of my model look like this:

include ActionView::Helpers::SanitizeHelper  class Post < ActiveRecord::Base {   before_validation :clean_input    ...    protected    def clean_input     self.input = sanitize(self.input, :tags => %w(b i u))   end end 

Needless to say, this doesn't work. I get the following error when I try and save a new Post.

undefined method `white_list_sanitizer' for #<Class:0xdeadbeef> 

Apparently, SanitizeHelper creates an instance of HTML::WhiteListSanitizer, but when I mix it into my model it can't find HTML::WhiteListSanitizer. Why? What can I do about this to fix it?

Answer 1

Just change the first line as follows :

include ActionView::Helpers 

that will make it works.

UPDATE: For Rails 3 use:

ActionController::Base.helpers.sanitize(str) 

Credit goes to lornc's answer

Answer 2

This gives you just the helper method without the side effects of loading every ActionView::Helpers method into your model:

ActionController::Base.helpers.sanitize(str)