Using FontAwesome with Rails was really easy with font-awesome-rails gem. It also had really nice helpers. Thing is this gem depends on Sprokets. I wanted to try the shiny but very light Propshaft to be inline with modern Rails.

I had 2 options:

1. Copy the SVG codes individual icons as needed and use them as part of view. (Easy)
2. Consigure FontAwesome as part of build process. (Some work, Easy to update)

I went for 2nd route, mainly because I didn't want to store bunch of SVG codes in my main codebase.

The following solution works on a Rails 7 app configured with cssbundling-rails gem.

First of all, let's install fontawesome and sass to package that.

yarn add sass
yarn add @fortawesome/fontawesome-free

I used v6, but if you need v5, specify the version.

Next, create a entrypoint for sass, call it app/assets/stylesheets/fontawesome.scss:

$fa-font-path: "./webfonts";

@import "@fortawesome/fontawesome-free/scss/regular";
@import "@fortawesome/fontawesome-free/scss/brands";
@import "@fortawesome/fontawesome-free/scss/solid";
@import "@fortawesome/fontawesome-free/scss/fontawesome";

You may comment out any of regular, brands and solid, if you're not using. The main magic here is the line $fa-font-path: "./webfonts";. Without this line, propshaft will fail to find the fonts assets.

Now let's add a task for yarn in package.json to build the files, add the following the scripts section:

"build:css:fontawesome": "cp -r ./node_modules/@fortawesome/fontawesome-free/webfonts ./app/assets/builds && sass ./app/assets/stylesheets/fontawesome.scss ./app/assets/builds/fontawesome.css --no-source-map --load-path=node_modules --quiet"

Final step, include it in the layout (application.html.erb or anywhere else):

<%= stylesheet_link_tag "fontawesome", "data-turbo-track": "reload" %>

Now you can build the assets with the following command, and propshaft will heapily serve it:

yarn build:css:fontawesome

One extra step would be adding the command as part of bin/dev. You can simple add the following line as part of your Procfile.dev:

fa: yarn build:css:fontawesome --watch

Now, whenever you would run bin/dev, fontawesome will be compiled for you.

For me, this works. If you have any nicer solution, please let me know in the comments below.

Note: If you already have a SASS setup, you may want to move the content of app/assets/stylesheets/fontawesome.scss to your application.scss or your other entrypoint file, instead of creating another entrypoint. That should work fine as well.