tail_log.rb

# Capistrano task for tailing logs on multiple servers

desc "tail log files, use '-s grep=[search text]' and '-s file=[file name]' to grep and tail specific file respectively" 
task :tail_logs, :roles => :app do
  set :grep, fetch(:grep, "")
  set :file, fetch(:file,"~/current/log/production.log")
  set(:g) { (grep == "") ? "" : " | grep #{grep}" }
  run "tail -f #{file} #{g}" do |channel, stream, data|
    #put hostname in front of each line 
    puts "#{data}".gsub( /(^)/i,"#{channel[:host]} \\1")
    break if stream == :err    
  end
end