Rake tasks for cutting a branch and deploying to a Heroku target. This works best when you have the Heroku Labs "preboot" feature enabled. Primarily, this is for deploys that do not have migrations. Migration deploys is still a work in progress and depends on the contents of the migration. (See http://pedro.herokuapp.com/past/2011/7/13/rails_mig…

heroku.rake

def migrate_db(remote)
  # sh %{heroku maintenance:on --remote #{remote}} || fail
  sh %{heroku run --remote #{remote} bundle exec rake db:migrate} || fail
  # sh %{heroku maintenance:off --remote #{remote}} || fail
end

def zero_deploy(environment, remote, branch)
  original_path = pwd
  deploy_name = "#{environment}_#{Time.now.strftime("%Y-%m-%d-%H-%M")}"
  puts "-> bundle exec rake deploy:monitor[#{deploy_name}]"
  Dir.mktmpdir do |dir|
    cd dir
    sh %{git clone --no-hardlinks -b #{branch} --local #{original_path}} || fail
    cd "qcast"
    sh %{git checkout -b #{deploy_name}} || fail
    File.open("deploy.txt", 'w') do |f|
      f.puts(deploy_name)
      f.puts(`git log --pretty=format:'%h' -n 1`)
    end
    sh %{bundle exec rake assets:precompile RAILS_ENV=#{environment} } || fail
    sh %{git add .} || fail
    sh %{git commit -m 'Created deploy #{deploy_name}'} || fail
    sh %{git push origin #{deploy_name}} || fail
    cd original_path
    sh %{git push -f #{remote} #{deploy_name}:master} || fail
  end
end

namespace :deploy do
  desc "Deploy code to heroku"
  task :production, :branch do |t, args|
    args.with_defaults(:branch => "master")
    zero_deploy("production", "heroku", args[:branch])
  end
  
  task :staging, :branch do |t, args|
    args.with_defaults(:branch => "master")
    zero_deploy("staging", "staging", args[:branch])
  end
  
  task :monitor, :deployment do |t, args|
    while !system %{curl -s http://#{args[:deployment][/production/] ? "www.nextread.me" : "staging-qcast.herokuapp.com"}/admin/monitor | grep #{args[:deployment]}}
      print '*'
      sleep 5
    end
    puts " Done \a\a\a"
  end
  
  namespace :db do
    desc "Migrate the DB on Heroku"
    task :production do
      migrate_db("heroku")
    end
    
    task :staging do
      migrate_db("staging")
    end
  end
end

Nice, I'll review and see how we'd like to proceed :D