Display current git branch in your web app

If you work with Ruby on Rails on a web application already released to production, you surely have one browser tab on the prod app, and another one on localhost:3000. You may already have tried to reproduce a bug wondering why the debugger command won’t work just to realize five long minutes later that you were on the production tab…

Here is a trick to display the current git branch you are working on in your development browser tab. That way, your eye will catch on the orange badge and figure out quicker where you are. Plus you get a nice benefit of knowing the feature context.

# app/helpers/application_helper.rb
module ApplicationHelper
  def branch_info
    branch_name = `git rev-parse --abbrev-ref HEAD`
    content_tag :li do
      content_tag :p, :class => "navbar-text" do
        content_tag :span, branch_name, :class => "label label-warning"
      end
    end
  end
end

This helper is ready to be used in your bootstrap top bar menu, inside a ul.nav.

<!-- app/views/layout/application.html.erb -->
<div class="nav-collapse collapse">
  <ul class="nav">
    <%= branch_info if Rails.env.development? %>
  </ul>
</div>

You will get a nice orange badge in the top bar of your web application reminding you that:

1. You are in your development environment.
2. Which feature branch you are working on.

Before coming with the shell approach, I was previously using the gem grit:

repository = Grit::Repo.new(Rails.root)
branch_name = repository.head.name

But I figured out that I just needed the branch name, so including a gem was a bit of overhead!

What about you? Which trick do you use in the development environment? Have you tried rails-footnotes?