NAME

Plack::Middleware::ServerStatus::Lite - show server status like Apache's mod_status

SYNOPSIS

  use Plack::Builder;

  builder {
      enable "Plack::Middleware::ServerStatus::Lite",
          path => '/server-status',
          allow => [ '127.0.0.1', '192.168.0.0/16' ],
          counter_file => '/tmp/counter_file',
          scoreboard => '/var/run/server';
      $app;
  };

  % curl http://server:port/server-status
  Uptime: 1234567789
  Total Accesses: 123
  BusyWorkers: 2
  IdleWorkers: 3
  --
  pid status remote_addr host method uri protocol ss
  20060 A 127.0.0.1 localhost:10001 GET / HTTP/1.1 1
  20061 .
  20062 A 127.0.0.1 localhost:10001 GET /server-status HTTP/1.1 0
  20063 .
  20064 .

  # JSON format
  % curl http://server:port/server-status?json
  {"Uptime":"1332476669","BusyWorkers":"2",
   "stats":[
     {"protocol":null,"remote_addr":null,"pid":"78639",
      "status":".","method":null,"uri":null,"host":null,"ss":null},
     {"protocol":"HTTP/1.1","remote_addr":"127.0.0.1","pid":"78640",
      "status":"A","method":"GET","uri":"/","host":"localhost:10226","ss":0},
     ...
  ],"IdleWorkers":"3"}

DESCRIPTION

Plack::Middleware::ServerStatus::Lite is a middleware that display server status in multiprocess Plack servers such as Starman and Starlet. This middleware changes status only before and after executing the application. so cannot monitor keepalive session and network i/o wait.

CONFIGURATIONS

path

  path => '/server-status',

location that displays server status

allow

  allow => '127.0.0.1'
  allow => ['192.168.0.0/16', '10.0.0.0/8']

host based access control of a page of server status. supports IPv6 address.

scoreboard

  scoreboard => '/path/to/dir'

Scoreboard directory, Middleware::ServerStatus::Lite stores processes activity information in

counter_file

  counter_file => '/path/to/counter_file'

Enable Total Access counter

skip_ps_command

  skip_ps_command => 1 or 0

ServerStatus::Lite executes `ps command` to find all worker processes. But in some systems that does not mount "/proc" can not find any processes. IF 'skip_ps_command' is true, ServerStatus::Lite does not `ps`, and checks only processes that already did process requests.

TOTAL BYTES

The largest integer that 32-bit Perl can store without loss of precision is 2**53. So rather than getting all fancy with Math::BigInt, we're just going to be conservative and wrap that around to 0. That's enough to count 1 GB per second for a hundred days.

WHAT DOES "SS" MEAN IN STATUS

Seconds since beginning of most recent request

AUTHOR

Masahiro Nagano <kazeburo {at} gmail.com>

LICENSE

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.