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Mojo::Reactor::POE - POE backend for Mojo::Reactor


  use Mojo::Reactor::POE;

  # Watch if handle becomes readable or writable
  my $reactor = Mojo::Reactor::POE->new;
  $reactor->io($first => sub {
    my ($reactor, $writable) = @_;
    say $writable ? 'First handle is writable' : 'First handle is readable';

  # Change to watching only if handle becomes writable
  $reactor->watch($first, 0, 1);

  # Turn file descriptor into handle and watch if it becomes readable
  my $second = IO::Handle->new_from_fd($fd, 'r');
  $reactor->io($second => sub {
    my ($reactor, $writable) = @_;
    say $writable ? 'Second handle is writable' : 'Second handle is readable';
  })->watch($second, 1, 0);

  # Add a timer
  $reactor->timer(15 => sub {
    my $reactor = shift;
    say 'Timeout!';

  # Start reactor if necessary
  $reactor->start unless $reactor->is_running;

  # Or in an application using Mojo::IOLoop
  use POE qw(Loop::IO_Poll);
  use Mojo::Reactor::POE;
  use Mojo::IOLoop;
  # Or in a Mojolicious application
  $ MOJO_REACTOR=Mojo::Reactor::POE POE_EVENT_LOOP=POE::Loop::IO_Poll hypnotoad script/myapp


Mojo::Reactor::POE is an event reactor for Mojo::IOLoop that uses POE. The usage is exactly the same as other Mojo::Reactor implementations such as Mojo::Reactor::Poll. Mojo::Reactor::POE will be used as the default backend for Mojo::IOLoop if it is loaded before Mojo::IOLoop or any module using the loop. However, when invoking a Mojolicious application through morbo or hypnotoad, the reactor must be set as the default by setting the MOJO_REACTOR environment variable to Mojo::Reactor::POE.

Note that if POE detects multiple potential event loops it will fail. This includes IO::Poll and Mojo::IOLoop (loaded by Mojolicious) if the appropriate POE::Loop modules are installed. To avoid this, load POE before any Mojolicious module, or specify the POE event loop explicitly. This means that for Mojolicious applications invoked through morbo or hypnotoad, the POE event loop may also need to be set in the environment. See "Using POE with Other Event Loops" in POE::Kernel.


Mojo::Reactor::POE inherits all events from Mojo::Reactor::Poll.


Mojo::Reactor::POE inherits all methods from Mojo::Reactor::Poll and implements the following new ones.


  my $reactor = Mojo::Reactor::POE->new;

Construct a new Mojo::Reactor::POE object.


  $reactor->again($id, 0.5);

Restart timer and optionally change the invocation time. Note that this method requires an active timer.



Run reactor until an event occurs or no events are being watched anymore. Note that this method can recurse back into the reactor, so you need to be careful.

  # Don't block longer than 0.5 seconds
  my $id = $reactor->timer(0.5 => sub {});


  my $id = $reactor->recurring(0.25 => sub {...});

Create a new recurring timer, invoking the callback repeatedly after a given amount of time in seconds.


  my $bool = $reactor->remove($handle);
  my $bool = $reactor->remove($id);

Remove handle or timer.



Remove all handles and timers.


  my $id = $reactor->timer(0.5 => sub {...});

Create a new timer, invoking the callback after a given amount of time in seconds.


  $reactor = $reactor->watch($handle, $readable, $writable);

Change I/O events to watch handle for with true and false values. Note that this method requires an active I/O watcher.

  # Watch only for readable events
  $reactor->watch($handle, 1, 0);

  # Watch only for writable events
  $reactor->watch($handle, 0, 1);

  # Watch for readable and writable events
  $reactor->watch($handle, 1, 1);

  # Pause watching for events
  $reactor->watch($handle, 0, 0);


When using Mojo::IOLoop with POE, the event loop must be controlled by Mojo::IOLoop or Mojo::Reactor::POE, such as with the methods "start" in Mojo::Reactor::Poll, "stop" in Mojo::Reactor::Poll, and "one_tick". Starting or stopping the event loop through POE will not provide required functionality to Mojo::IOLoop applications.

Externally-added sessions will not keep the Mojo::IOLoop running if Mojo::Reactor::POE has nothing left to watch. This can be worked around by adding a recurring timer for the reactor to watch.


POE has a complex session system which may lead to bugs when used in this manner. Report any issues on the public bugtracker.


Dan Book,


Copyright 2015, Dan Book.

This library is free software; you may redistribute it and/or modify it under the terms of the Artistic License version 2.0.


Mojolicious, Mojo::IOLoop, POE