Rakefile

require "rubygems"
require "bundler/setup"

require 'active_record'
require 'yaml'

namespace :db do
  def create_database config
    options = {:charset => 'utf8', :collation => 'utf8_unicode_ci'}

    create_db = lambda do |config|
      if config['adapter']!='sqlite3'
        ActiveRecord::Base.establish_connection config.merge('database' => nil)
        ActiveRecord::Base.connection.create_database config['database'], options
      end
      ActiveRecord::Base.establish_connection config
    end

    begin
      create_db.call config
    rescue Exception => sqlerr
      if defined? Mysql::Error and sqlerr.is_a? Mysql::Error
        if sqlerr.errno == 1405
          print "#{sqlerr.error}. \nPlease provide the root password for your mysql installation\n>"
          root_password = $stdin.gets.strip

          grant_statement = <<-SQL
          GRANT ALL PRIVILEGES ON #{config['database']}.* 
            TO '#{config['username']}'@'localhost'
            IDENTIFIED BY '#{config['password']}' WITH GRANT OPTION;
        SQL

          create_db.call config.merge('database' => nil, 'username' => 'root', 'password' => root_password)
        else
          $stderr.puts sqlerr.error
          $stderr.puts "Couldn't create database for #{config.inspect}, charset: utf8, collation: utf8_unicode_ci"
          $stderr.puts "(if you set the charset manually, make sure you have a matching collation)" if config['charset']
        end
      else
        # We rescued all Exceptions so throw the rest of them.
        # raise with no parameters reraises the exception in $!
        raise
      end
    end
  end
 
  task :environment do
    DATABASE_ENV = ENV['DATABASE_ENV'] || 'development'
    MIGRATIONS_DIR = ENV['MIGRATIONS_DIR'] || 'db/migrate'
    DATABASE_CONFIG_FILE = ENV['DATABASE_CONFIG_FILE'] || 'config/database.yml'
  end

  task :configuration => :environment do
    @config = YAML.load_file(DATABASE_CONFIG_FILE)[DATABASE_ENV]
  end

  task :configure_connection => :configuration do
    ActiveRecord::Base.establish_connection @config
    ActiveRecord::Base.logger = Logger.new STDOUT if @config['logger']
  end

  desc 'Create the database from config/database.yml (or supplied in DATABASE_CONFIG_FILE env var) for the current DATABASE_ENV'
  task :create => :configure_connection do
    create_database @config
  end

  desc 'Drops the database for the current DATABASE_ENV'
  task :drop => :configure_connection do
    ActiveRecord::Base.connection.drop_database @config['database']
  end

  desc 'Migrate the database (options: VERSION=x, VERBOSE=false).'
  task :migrate => :configure_connection do
    ActiveRecord::Migration.verbose = true
    ActiveRecord::Migrator.migrate MIGRATIONS_DIR, ENV['VERSION'] ? ENV['VERSION'].to_i : nil
  end

  desc 'Rolls the schema back to the previous version (specify steps w/ STEP=n).'
  task :rollback => :configure_connection do
    step = ENV['STEP'] ? ENV['STEP'].to_i : 1
    ActiveRecord::Migrator.rollback MIGRATIONS_DIR, step
  end

  desc "Retrieves the current schema version number"
  task :version => :configure_connection do
    puts "Current version: #{ActiveRecord::Migrator.current_version}"
  end
end