Rake Tutorial

http://www.railsenvy.com/2007/6/11/ruby-on-rails-rake-tutorial

Rake来自Make

Make将编译过而且没改动过的源文件与改动过的源文件区分开来，做增量build

Rake不管编译这茬事

Rake使用Ruby语言

Rails里的rake任务放在lib/tasks目录

例子:lib/tasks/something.rake

namespace :utils do
  desc "Create blank directories if they don't already exist"
  task(:create_direcotries) do
  
    # The folders I need to craete
    shared_folders = ["icons", "images", "groups"]
    
    for folder in shared_folders
    
      # Check to see if it exists
      if File.exists?("#{RAILS_ROOT}	/public/#{folder}")
        puts "#{RAILS_ROOT}/public/#{folder} exists"
      else
        puts "#{RAILS_ROOT}/public/#{folder} doesn't exist so we're creating"
        Dir.mkdir "#{RAILS_ROOT}/public/#{folder}"
      end
     
    end
     
  end
end

rake --task可以看到当前可以使用的rake任务

:environment任务让我们可以使用Rails Models

namespace :utils do
  desc "Finds soon to expire subscriptions and emails users"
  task(:send_expire_soon_emails => :environment) do
        # Find users to email
        for user in User.members_soon_to_expire
                puts "Emailing #{user.name}"
                UserNotifier.deliver_expire_soon_notification(user)
        end
  end
end