Display current github branch name in your rails app when working with Capistrano

application.html.erb

<!-- app/views/layout/application.html.erb -->

<% if !Rails.env.production? %>
  <%= branch_info %>
<% end %>

application_helper.rb

# app/helpers/application_helper.rb

module ApplicationHelper
  def branch_info
    if Rails.env.staging?
      #this will be changed after code is deployed to staging server
      branch_name = 'BranchName'
    else
      #this works in local
      branch_name = `git rev-parse --abbrev-ref HEAD` 
    end
    content_tag :span, branch_name, :class => "label label-warning"
  end
end

deploy.rb

#config/deploy.rb

#set the branch name variable
set :branch_name, `git rev-parse --abbrev-ref HEAD`

#after the new version of app code has been uploaded to the server, edit the view file to update "BranchName" with the current branch variable as set above
#server restart is required due to caching 
after "deploy:update_code" do
  run "cd #{current_release}; sed -i 's/BranchName/#{branch_name}/g' app/helpers/application_helper.rb"
  run "cd #{current_release}; touch tmp/restart.txt"
end

staging.rb

#config/deploy/staging.rb

#this file isn't necessary for the github labelling but it's useful all the same
#set capistrano to deploy from your current branch
set :branch_name, `git rev-parse --abbrev-ref HEAD`
set :branch, "#{branch_name}"