Kill postgres connections upon rake db:drop

kill_postgres_connections.rake

# lib/tasks/kill_postgres_connections.rake
desc "Kills postgres connections"
task :kill_postgres_connections => :environment do
  yml_file = Rails.root.join('config/database.yml')
  db_settings = YAML::load(File.open(yml_file))[Rails.env]
  db_name = db_settings['database']
  sh = <<EOF
ps -e |
grep postgres: |
grep #{db_name} |
cut -d ':' -f 3 |
awk '{print $1}' |
xargs kill
EOF
  puts "Killing db connections to #{db_name}"
  `#{sh}`
end

task "db:drop" => :kill_postgres_connections