ruby.capistrano.sheet

  This work is licensed under the Creative Commons
  Attribution-NonCommercial-NoDerivs 2.0 License. To
  view a copy of this license, visit
  http://creativecommons.org/licenses/by-nc-nd/2.0/ukn
  ########## Shell Commands ##########  
  Installation:
  $ gem install capistrano
  Add your application to Capistrano (capistranize):
  $ cap --apply-to /path/to/your/app YourApplicationName
  # NOTE: Rake access to capistrano is deprecated in Capistrano 1.3.
  #       Use the 'cap' command instead.
  Execute the setup task:
  $ rake remote:exec ACTION=setup
  Execute the cold_deploy task:
  $ rake remote:exec ACTION=cold_deploy
  Deploy your application:
  $ rake deploy
  Similar to deploy, but it runs the migrate task on the new release before updating the symlink:
  $ rake remote:deploy_with_migrations
  Rollback a release from production:
  $ rake rollback
  Execute the disable_web task:
  $ rake remote_exec ACTION=disable_web 
  UNTIL=\"tomorrow morning\" 
  REASON=\"vital upgrade\"
  Using the invoke task:
  $ rake remote_exec ACTION=invoke 
  COMMAND=\"svn up /u/apps/flipper/current/app/views\" 
  ROLES=appn
  ########## Standard Tasks ##########
  cleans up the releases directory, leaving the five most recent releases:
  $ cap cleanup 
  used when deploying an application for the first time. Starts the applicatioxE2\x80\x99s 
  spinner (via the spinner task) and then does a normal deploy:
  $ cap cold_deploy 
  updates all the code on your server (via update_code and symlink
  tasks), then restarts the FastCGI listeners on the application servers (via
  the restart task):
  $ cap deploy
  prints the difference between what was last deployed, and what is
  currently in your repository:
  $ cap diff_from_last_deploy
  puts up a static maintenance page that is displayed to visitors:
  $ cap disable_web
  removes the maintenance page:
  $ cap enable_web
  allows you to send commands directly:
  $ cap invoke
  changes to the directory of your current release (as indicated by the
  current symlink), and runs rake RAILS_ENV=production migrate:
  $ cap migrate
  restarts all FastCGI listeners for your application by calling the reaper
  command without arguments. Only executed on :app servers
  $ cap restart
  rolls your application back to the previously deployed version
  determines the previous release , updates the current symlink to point
  to that, and then deletes the latest release
  $ cap rollback
  Creates and chmods the directory tree properly:
  $ cap setup
  inspect the existing tasks and display them to standard out in
  alphabetical order, along with their descriptions:
  $ cap show_tasks
  starts the spinner process for your application:
  $ cap spinner
  updates the current symlink to the latest deployed version of the code
  $ cap symlink
  Checks out your source code, deletes the log and public/system
  directories in your new release, symlinks log to
  #{shared_path}/log, symlinks public/system to #{shared_path}/system:
  $ cap update_coden
  ########## config/deploy.rb ##########
  *Defining Tasks
  task :hello_world do  run \"echo Hello, $HOSTNAME\"
  end
  task :hello_world, :roles => [:db, :app] do  puts \"calling hello_world...\"  hello_world
  end
  *Transactions
  task :cold_deploy do  transaction do    task_one_here    task_two_here  end  task_three_not_in_transaction
  end
  *Capturing output with run
  run \"sudo ls -la\" do |channel, stream, data|  if data =~ /^Password:/    logger.info \"#{channel[:host]} asked for password\"    channel.send_data \"mypass\"  end
  end
  buffer = render(:template => 
  <<EXAMPLE_TEMPLATE)  This template will be rendered replacing variables  <%= like_this_variable =>  with their values.
  EXAMPLE_TEMPLATE
  put buffer, \"path/to/save/file.txt\", :mode => 0755
  * multi-stage
  set :stages, %w(staging production testing) # [optional] defaults to [development, test, staging?, production].
  set :default_stage, \"testing\" # [optional] if omitted, cap aborts if you don't specify in args
  require 'capistrano/ext/multistage'
  Stage-specific code in config/deploy/staging.rb and config/deploy/production.rb. 
  see: http://weblog.jamisbuck.org/2007/7/23/capistrano-multistage
  *deploy.rb variables and their defaults
  The name of your application. 
  :application  (required)  
  The location of your code\xE2\x80\x99s scm repository
  :repository  (required)  
  The address of the server to use as a gateway. 
  :gateway  nil    
  The name of the user to use when logging into the remote host(s).
  :user    current_user  
  The password to use for logging into the remote host(s).
  :password  password  
  The root of the directory tree on the remote host(s) that the 
  application should be deployed to
  :deploy_to  \xE2\x80\x9C/u/apps/#{application}\xE2\x80\x9D
  The directory under deploy_to that should contain each deployed revision.
  :version_dir  releases  
  The name to use (relative to deploy_to) for the symlink that points at 
  the current release
  :current_dir  current    
  The name of the directory under deploy_to that will contain directories and files to be shared between all releases.
  :shared_dir  shared  
  This specifies the revision you want to check out on the remote machines.
  :revision  (latest)  
  The source control module to use. 
  Current supported are :subversion, :cvs, :darcs
  :scm    subversion  
  The location on the remote host of the source control executable.
  :svn,:cvs,:darcs
  The subversion operation to use when checking out code on the remote host. 
  Can be set to \xE2\x80\x9Cexport\xE2\x80\x9D
  :checkout  \"co\"    
          
  Hash of additional options passed to the SSH connection routine.
  This lets you set (among other things) a non-standard port to connect on:
  (ssh_options[:port] = 2345)
  :ssh_options  Hash.new  
          
  Whether or not tasks that can use sudo, ought to use sudo. In a shared environment, this is typically not desirable (or possible), and 
  in that case you should set this variable to false
  :use_sudo  true    
  Sets the path to sudo.
  :sudo        
  variables are set via:
  set :application, \"flipper\"n
  ########## Interactive Shell ##########      (requires capistrano-1.2.0)
  Shell is essentially a SSH interface to your
  servers, so you can run standard commands such 
  as 'ls' or 'cp' as well as Capistrano-specific ones.
  Start the interactive Capistrano shell
  $ cap -v shell
  Execute Capistrano tasks
  cap> !deploy
  cap> !update_code symlink
  cap> !setup deploy
  cap> on app2.foo.com !setup
  cap> with app,db !setup deploy"