run the shell script from rails application after login to the remote system

Question

I want to run a shell script from my Rails application. The script is started on the remote server via the net-ssh Gem. Here is my code:

Net::SSH.start('localhost', 'user', :password => '1234', :port => port) do |session|
  session.exec!("#{Rails.root}/script/myscript")
end

I have checked that the script is present in my local application. Script is taking about 1 hour for completion. I have two questions:

1. Is this the right way for doing this?
2. How can I run the script in the background?

Answer 1

1. The sample doc says that the simple, and quite proper way to run the Net::SSH session is the following:

   HOST = '192.168.1.113'
   USER = 'username'
   PASS = 'password'
   
   Net::SSH.start( HOST, USER, :password => PASS ) do| ssh |
      result = ssh.exec! 'ls'
      puts result
   end
   

   I recomment to pass at least password argument via shell environment to don't store it in the script plainly. Also you could use micro-optparse gem to pass other argument via command line. So it could be as follows:

   require 'micro-optparse'
   
   options = Parser.new do |p|
      p.banner = "This is a fancy script, for usage see below"
      p.version = "fancy script 0.0 alpha"
      p.option :host, "set host", :default => 'localhost'
      p.option :host, "set user", :default => ''
   end.parse!
   
   Net::SSH.start( options[ :host ], options[ :user ], :password => ENV[ 'PASSWORD' ] ) do| ssh |
      result = ssh.exec! 'ls'
      puts result
   end
   

   And run from command line:

   $ bundle exec ./1.rb --host=111.ru --user=user
   {:host=>"111.ru", :user=>"user"}
   

   Of course the support for :port argument can be added in the same manner.

2. Use nohup or screen utitilies to run a script as a service in linux:

   result = ssh.exec! "nohup #{Rails.root}/script/myscript"