Remoting

Remoting is a great way to turn plain rake tasks in scripts to manage your production server remotely. It provides a little framework to run remote commands over SSH along with a DSL to define remote scripts. Interactive tasks that involves sudo are supported too.

Install

gem 'remoting'

Update your bundle

bundle install

Generate remote.yml stub

rails g remoting:install

Edit config/remote.yml

remote:
  any_setting_you_like: Here you can define properties that will be available in 'config' struct inside rake tasks!
  example: Below are some tipical configuration settings you may wish to define ...
  login: user@server
  dest: /var/ror/myapp
  repo: git@gitserver:myapp.git
  ruby: 1.9.3
  gemset: myapp

Usage

Just require remoting/task inside your tasks. NOTE: you can also require it globally but is not recommended cause here String is patched to enable bash-flavoured syntax.

ex.

desc "Restart the server"
task :restart do
  require 'remoting/task'

  remote('restart', config.login) do
   mkdir '-p', config.dest.join('tmp')
   touch config.dest.join('tmp', 'restart.txt') 
  end

end

Methods invoked inside the remote block are executed inside a ssh session. remote takes two arguments: name and login. name serves only for logging purposal while login is the login string to access the server supplied in the form of user@host

DSL

By examples

remote("my task", config.login) do 

  ps("aux") | grep("mysql") 
  echo 'noise' > "/dev/null"
  echo 'setting=value' >> "settings.conf"
  tail -100 config.dir.join('log', 'logfile.log')
  command("[[ -f \"path\" ]] && run_a_command")

end

Local Tasks using DSL

You can also define local tasks using the same DSL

desc "Setup git origin"
task :init do
  require 'remoting/task'

  local('init') do
    git :init
    git :remote, :add, :origin, config.repo
  end  
end

Methods invoked inside the local block are executed locally. local takes only the name parameter.

Interactive tasks

Invoking remote with :interactive => true will tell remote to yield the process to ssh, this way you will remotely interact with the server. On the other side everithing that is supposed to be executed after remote wont run. Despite this interactive tasks are very useful.

# my_remote_task.rake

desc "Open rails console on server"
task :console do
  require 'remoting/task'

  remote('console', config.login, :interactive => true) do
    cd config.dest
    source '$HOME/.rvm/scripts/rvm'
    bundle :exec, "rails c production"
  end
end

Example 2. Reloading Apache configuration (involves sudo):

task :reload do
  require 'remoting/task'

  remote('reload', config.login, :interactive => true) do
    sudo "/etc/init.d/apache2 reload"
  end
end

Recipes

A complete deployment manager (like Capistrano even if probably not as good as it is) can be easily built over remoting. Capistrano recipes can be ordinary rake tasks packed as gems. Plus various deployment strategies can be assembled as dependencies of a main deploy task.

As from version 0.3.2 Remoting added support for recipes with a generator (rails g remoting:recipe) that basically installs recipes from remoting/recipes into lib/tasks/remote.

eg.

rails g remoting:recipe rails git bare apache slow_assets_workaround

Examples

You can find more examples under examples source directory

Coming Soon

  • Ability to define bunch of commands as functions
  • Pre-packed strategies

Copyright (c) 2012 mcasimir

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

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