can't import less.erb file with interpolated strings

[Steven Spiel]

I'm on rails 4.2.5 with less-rails 2.7.1 and I'm having issues importing less.erb files.

My manifest file:

application.less:

@import 'base';
@import 'layout';
@import 'module';
@import 'state';
@import 'theme.less.erb';

/*
 *= require_tree .
 *= require_self
 */

and theme.less.erb is

.ui.button {
  color: <%= @branding.primary_color %>
}

Without the erb interpolation, it does fine, but otherwise, it raises:

Unrecognised input

The @branding variable is being set in application_controller.rb:

def render(*args)
  @branding = Branding.new(cookies, params)
  super
end

But the erb interpolation doesn't work even without the variable:

.ui.button {
  color: <%= '#ffffff' %>
}

I'd really like to have some per-user basis branding that is compiled (and possibly cached) on the fly. What do you suggest?

[Brendon Muir]

Since the asset is compiled at a different time to your request (i.e. when deploying into production) it won't have access to your request. I've solved this problem by inlining some override CSS in a <style> tag in the head of the page. If you use Turbolinks you'll need to add this into the body of the page.