Eye

Process monitoring tool. An alternative to God and Bluepill. With Bluepill like config syntax. Requires MRI Ruby >= 1.9.3-p194. Uses Celluloid and Celluloid::IO.

Little demo, shows general commands and how chain works:

Recommended installation on the server (system wide):

$ sudo /usr/local/ruby/1.9.3/bin/gem install eye
$ sudo ln -sf /usr/local/ruby/1.9.3/bin/eye /usr/local/bin/eye

Config example, shows some typical processes and most of the options (see in exampes/ folder):

examples/test.eye

# load submodules, here just for example
Eye.load("./eye/*.rb") 

# Eye self-configuration section
Eye.config do
  logger "/tmp/eye.log"
end

# Adding application
Eye.application "test" do
  # All options inherits down to the config leafs.
  # except `env`, which merging down

  working_dir File.expand_path(File.join(File.dirname(__FILE__), %w[ processes ]))
  stdall "trash.log" # stdout,err logs for processes by default
  env "APP_ENV" => "production" # global env for each processes
  triggers :flapping, :times => 10, :within => 1.minute, :retry_in => 10.minutes
  checks :cpu, :below => 100, :times => 3 # global check for all processes

  group "samples" do
    chain :grace => 5.seconds # chained start-restart with 5s interval, one by one.

    # eye daemonized process
    process :sample1 do
      pid_file "1.pid" # pid_path will be expanded with the working_dir
      start_command "ruby ./sample.rb"
      daemonize true
      stdall "sample1.log"

      checks :cpu, :below => 30, :times => [3, 5]
    end

    # self daemonized process
    process :sample2 do
      pid_file "2.pid"
      start_command "ruby ./sample.rb -d --pid 2.pid --log sample2.log"
      stop_command "kill -9 {PID}"

      checks :memory, :below => 300.megabytes, :times => 3
    end
  end

  # daemon with 3 childs
  process :forking do
    pid_file "forking.pid"
    start_command "ruby ./forking.rb start"
    stop_command "ruby forking.rb stop"
    stdall "forking.log"

    start_timeout 5.seconds
    stop_grace 5.seconds

    monitor_children do
      restart_command "kill -2 {PID}" # for this child process
      checks :memory, :below => 300.megabytes, :times => 3
    end
  end

  # eventmachine process, daemonized with eye
  process :event_machine do |p|
    pid_file 'em.pid'
    start_command 'ruby em.rb'
    stdout 'em.log'
    daemonize true
    stop_signals [:QUIT, 2.seconds, :KILL]

    checks :socket, :addr => "tcp://127.0.0.1:33221", :every => 10.seconds, :times => 2, 
                    :timeout => 1.second, :send_data => "ping", :expect_data => /pong/
  end

  # thin process, self daemonized
  process :thin do
    pid_file "thin.pid"
    start_command "bundle exec thin start -R thin.ru -p 33233 -d -l thin.log -P thin.pid"
    stop_signals [:QUIT, 2.seconds, :TERM, 1.seconds, :KILL]

    checks :http, :url => "http://127.0.0.1:33233/hello", :pattern => /World/, :every => 5.seconds, 
                  :times => [2, 3], :timeout => 1.second
  end

end

Start monitoring and load config:

$ eye l(oad) examples/test.eye

load folder with configs:

$ eye l examples/
$ eye l examples/*.rb

Load also uses for config synchronization and load new application into runned eye daemon. Light operation, so i recommend to use with every deploy (and than restart processes). (for processes with option stop_on_delete, load becomes a tool for full config synchronization, which stopps deleted from config processes).

Process statuses:

$ eye i(nfo)

test                       
  samples                          
    sample1 ....................... up  (21:52, 0%, 13Mb, <4107>)
    sample2 ....................... up  (21:52, 0%, 12Mb, <4142>)
  event_machine ................... up  (21:52, 3%, 26Mb, <4112>)
  forking ......................... up  (21:52, 0%, 41Mb, <4203>)
    child-4206 .................... up  (21:52, 0%, 41Mb, <4206>)
    child-4211 .................... up  (21:52, 0%, 41Mb, <4211>)
    child-4214 .................... up  (21:52, 0%, 41Mb, <4214>)
  thin ............................ up  (21:53, 2%, 54Mb, <4228>)

Commands:

start, stop, restart, delete, monitor, unmonitor

Command params (with restart for example):

$ eye r(estart) all
$ eye r test
$ eye r samples
$ eye r sample1
$ eye r sample*
$ eye r test:samples
$ eye r test:samples:sample1
$ eye r test:samples:sample*
$ eye r test:*sample*

Check config syntax:

$ eye c(heck) examples/test.eye

Log tracing:

$ eye trace 
$ eye tr test
$ eye tr sample

Quit monitoring:

$ eye q(uit)

Config explain (for debug):

$ eye explain examples/test.eye

Config api:

Waiting for pull requests ..., until that you can read examples and spec/dsl folders.