How to return HTML directly from a Rails controller?

One of my model objects has a 'text' column that contains the full HTML of a web page.

I'd like to write a controller action that simply returns this HTML directly from the controller rather than passing it through the .erb templates like the rest of the actions on the controller.

My first thought was to pull this action into a new controller and make a custom .erb template with an empty layout, and just <%= modelObject.htmlContent %> in the template - but I wondered if there were a better way to do this in Rails.

In your controller respond_to block, you can use:

render :text => @model_object.html_content

or:

render :inline => "<%= @model_object.html_content %>"

So, something like:

def show
  @model_object = ModelObject.find(params[:id])
  
  respond_to do |format|
    format.html { render :text => @model_object.html_content }
  end
end

In latest Rails (4.1.x), at least, this is much simpler than the accepted answer:

def show
  render html: '<div>html goes here</div>'.html_safe
end

Its works for me

def show
  @model_object = ModelObject.find(params[:id])

   respond_to do |format|
    format.html { render :inline => "<%== @model_object['html'] %>" }
  end
end