deploy.rb

namespace :deploy do

  def format_column(str, length)
    (length - str.length).times do
      str += ' '
    end
    str
  end
  
  def table_display(table_hsh, columns)
    rows = [columns]
    max_values = columns.map{|i| i.length }
    table_hsh.each_pair do |key, row_arr|
      row_arr.each do |row_hsh|
        row = [key]
        columns.each_with_index do |column, index|
          row << row_hsh[column] if row_hsh.has_key?(column)
        end
        row.each_with_index do |col, index|
          max_values[index] = col.to_s.length if col.to_s.length > max_values[index]
        end
        rows << row
      end
    end
    rows = rows.map do |row|
      formatted_row = []
      row.each_with_index do |col, index|
        formatted_row << format_column(col, max_values[index])
      end
      formatted_row
    end
    first = rows.delete_at(0)
    puts ''
    rows.sort{|x,y| x[0] <=> y[0]}.insert(0, first).each {|row| puts row.join(' | ')}
    puts ''
  end
  
  def extract_from_console(command, headers, remove_indexes=[])
    report = {}
    run("#{command}; true") do |channel, stream, data|
      if stream == :out
        data.split(/\n/).each do |raw_row|
          row = raw_row.split(' ')
          remove_indexes.each {|i| row.delete_at(i)}
          row[headers.count - 1] = row[headers.count - 1..row.length-1].join(' ') if headers.count < row.count  # join the rest of the array in the last column 
          report[channel[:server].to_s] ||= []
          report[channel[:server].to_s] << Hash[*headers.zip(row).flatten]
        end
      end
    end
    report
  end
  
  def extract_from_console_and_display(command, headers, remove_indexes=[])
    table_display(extract_from_console(command, headers, remove_indexes), ['Server'] + headers)
  end

  namespace :servers do 
    
    desc "clear logs"
    task :clear_logs, :roles => :jobs do
      run "rm #{shared_path}/log/*"
    end

    desc "Display free memory" 
    task :memory_usage, :roles => :jobs do
      headers = "Total Used Free Shared Buffers Cached".split
      extract_from_console_and_display("free -m | grep Mem", headers, [0])
    end
    
    desc "Display swap usage" 
    task :swap_usage, :roles => :jobs do
      headers = "total used free".split
      extract_from_console_and_display("free -m | grep Swap", headers, [0])
    end 
    
    desc "Display current disk usage"
    task :disk_space, :roles => :jobs do
      headers = ["Total Size","Used","Available","% Uses"]
      extract_from_console_and_display("df -h | grep ^/dev/", headers, [5, 0])
    end

    desc "Display all forever job instances currently running"
    task :running_forever_jobs, :roles => :jobs do
      headers = ["User", 'PID', '% CPU', '% Memory', 'VSZ', 'RSS', 'TTY', 'Stat', 'Start', 'Time', 'Command']
      extract_from_console_and_display("ps faux | grep 'Forever' | grep -v grep", headers)
    end
    
    desc "Display all delayed_job instances currently running"
    task :running_delayed_jobs, :roles => :jobs do
      headers = ["User", 'PID', '% CPU', '% Memory', 'VSZ', 'RSS', 'TTY', 'Stat', 'Start', 'Time', 'Command']
      extract_from_console_and_display("ps faux | grep 'delayed_job' | grep -v grep", headers)
    end
    
    task :kill_all_dj_jobs, :roles => :jobs do
      run("kill -9 `ps -ef | grep delayed_job | grep -v grep | awk '{print $2}'`; true")      
    end
    
    task :delayed_jobs_log, :roles => :jobs do
      trap("INT") { puts 'Interupted'; exit 0; }
      run "tail -f #{shared_path}/log/delayed_job.log" do |channel, stream, data|
        if stream == :out
          data.split(/\n/).each do |row|
            puts "#{channel[:host]}: #{row}" 
          end
        end
      end
    end
    
    task :missing_agent_errors, :roles => :jobs do
      puts (extract_from_console("tail -n 1000 #{shared_path}/log/red_file_updates.log | grep missing", [''])).to_yaml
    end

    task :dj_errors, :roles => :jobs do
      puts (extract_from_console("tail -n 1000 #{shared_path}/log/cdn_exception.log", [''])).to_yaml
    end
    
  end

end