How to excute commands with in Rake tasks

Question

I have the rake tasks in my rails application. i want to run a commandline commands with in rake task. how can i do this. i tried by the following but fails

desc "Sending the newsletter to all the users"

task :sending_mail do

run "cd #{RAILS_ROOT} && ar_sendmail -o -t NewsLetters -v"

system "cd #{RAILS_ROOT} && ar_sendmail -o -t NewsLetters -v &"

end

The above run command throws run method undefined & System command not throwing any errors but not executed.

i want to do this.. can any please correct me on this. how can defined correctly to run command lind commands

Answer 1

run is used by Capistrano and other things for launching commands, but Rake often makes use of Kernel#system instead.

Your command might be being run, but not working. Why not make a wrapper shell script you can test independently, or try and kick off using the full path:

newsletter_script = File.expand_path('ar_sendmail', RAILS_ROOT)

if (File.exist?(newsletter_script))
  unless (system(newsletter_script + ' -o -t NewsLetters -v &'))
    STDERR.puts("Script #{newsletter_script} returned error condition")
  end
else
  STDERR.puts("Could not find newsletter sending script #{newsletter_script}")
end

It would seem odd to have your script not in scripts/

The system call should return true on success. If this is not the case, either the script returned an error code, or the command could't be run.

Answer 2

This links may help you run command line command into ruby ...

http://zhangxh.net/programming/ruby/6-ways-to-run-shell-commands-in-ruby/

http://stackoverflow.com/questions/2232/calling-bash-commands-from-ruby

http://blog.jayfields.com/2006/06/ruby-kernel-system-exec-and-x.html

%x[command].each do |f|
  value = f
end