Class: Workers::System

Inherits:
Object
  • Object
show all
Extended by:
Resque::Plugins::Result
Defined in:
lib/workers/quorum.rb

Class Method Summary collapse

Class Method Details

.perform(meta_id, cmd, remote, ssh_host, ssh_user, ssh_options = {}, stdout = false) ⇒ Object

Resque worker method.



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# File 'lib/workers/quorum.rb', line 10

def self.perform(meta_id, cmd, remote, ssh_host, ssh_user, ssh_options = {}, stdout = false)
  unless ssh_options.empty?
    # Convert each key in ssh_options to a symbol.
    ssh_options = ssh_options.inject({}) do |memo, (k, v)|
      memo[k.to_sym] = v
    memo
    end
  end

  exit_status = 1
  out         = ""

  if remote
    # Execute command on remote machine.
    Net::SSH.start(ssh_host, ssh_user, ssh_options) do |ssh|
      ssh.open_channel do |ch|
        ch.exec(cmd) do |ch, success|
          if success
            # Capture STDOUT from ch.exec()
            if stdout
              ch.on_data do |ch, data|
                out = data
              end
            end
            # Read the exit status of the remote process.
            ch.on_request("exit-status") do |ch, data|
              exit_status = data.read_long
            end
          else
            Rails.logger.warn "Channel Net::SSH exec() failed. :'("
          end
        end
      end
      ssh.loop
    end
  else
    out         = `#{cmd}`
    exit_status = $?.exitstatus
  end
  if exit_status > 0
    raise "Worker failed :'(. See quorum/log/quorum.log for more information."
  end
  out if stdout
end