Question

Instead of having the page include a style tag with a link where to get the css from, which I could add to my view using rails’ stylesheet_link_tag helper method, I want to have the css inline directly inside the page.

This is what I came up with so far:

%style(type="text/css")=File.read(physical_asset_path("email.css"))

But I can’t find any rails’ helper method which gives me the physical path of an asset – physical_asset_path is just a dummy method invented by me.

Anybody knows how to get the physical path of an asset when using rails 3.2.x?

Is there an easier/ better way to get stylesheets – from css files inside the common rails assets paths – inline?

Use case: most email clients don’t access external sources (like css, images) without user confirmation. So to get the emails properly displayed I need to embed the CSS inside the emails’ HTML.

Answer 1

Use premailer or premailer-rails3

https://github.com/fphilipe/premailer-rails3
or
https://github.com/alexdunae/premailer

Joe’s Nerd Party say:

We also used the Premailer gem to automatically inline the linked
stylesheet in the email views. Our email layout looks something like:

%html
  %head
    = stylesheet_link_tag 'email'

    %style{:type => "text/css"}
      :sass
        @media all and (max-width: 480px)
          table#container
            width: auto !important
            max-width: 600px !important
         ... and so on for the mobile code

    %body 
      Email body here.
      %table
        Lots of tables.

We include a stylesheet in the HTML. Premailer downloads it, processes
it, and inserts the css rules inline in the HTML.

The @media rules need to be inline in the email layout, since
Premailer can’t handle those being in a separate css file yet.

We use premailer-rails3 to integrate Premailer into Rails 3.
Unfortunately, we found a bunch of bugs in premailer and
premailer-rails3. Our forks of the projects are at
https://github.com/joevandyk/premailer and
https://github.com/joevandyk/premailer-rails3. The forks fix some
encoding bugs, remove some weird css processing stuff done by
premailer-rails3, allow premailer to not strip out embedded
rules in the email layouts, and some other things.

We also found a bug in sass-rails, where you can’t embed image-urls in
inline sass code. See https://github.com/rails/sass-rails/issues/71
Premailer-rails3 hooks into ActionMailer when the email actually being
delivered, not just generated. When running tests, email is not
actually sent, so the premailer-rails3 hooks don’t get ran during
tests. I haven’t spent the time to see if it’s possible to get the
premailer processing to run during tests, but that would be a nice
thing to do.

Also, our forks on premailer-rails3 assume that you want premailer to
go out and actually download the linked CSS files. It should be
possible to use the Rails 3.1 asset pipeline to get the processed css
without downloading it. A very special thanks goes to Jordan Isip who
did the super annoying job of making sure the emails look great in all
the different clients out there. Writing that CSS/HTML did not look
fun.

Update:

Roadie appears to be a better option. Thanks to Seth Bro for pointing it out.