copy_remote_db_to_local.rb

# this assumes that it lives in the config directory

set :db_dump_filename, "/tmp/my_app.tar.gz"

namespace :db do
  desc 'Copy a remote database to the local development db'
  task :copy, :roles => :db, :only => {:primary => true} do
    remote_database_yml = capture("cat #{current_path}/config/database.yml")
    local_database_yml = File.read(File.dirname(__FILE__) + '/database.yml')
    remote_database_config = YAML::load(remote_database_yml)[rails_env]
    local_database_config = YAML::load(local_database_yml)['development']
    
    run "mysqldump #{database_options remote_database_config} | gzip > #{db_dump_filename}"
    get db_dump_filename, db_dump_filename
    run "rm -f #{db_dump_filename}"
    
    command = "gunzip -c #{db_dump_filename} | mysql #{database_options local_database_config}"
    puts "executing `#{command}`"
    system command
  end
  
  def database_options(config)
    options = ["-u #{config['username']}"]
    options << "-p#{config['password']}" if config['password'] && !config['password'].blank?
    options << "-h #{config['host']}" if config['host'] && !config['host'].blank?
    options << "-P #{config['port']}" if config['port'] && !config['port'].blank?
    options << "#{config['database']}"
    options * ' '
  end