Mojo::Reactor - Low-level event reactor base class

NAME  SYNOPSIS  DESCRIPTION  EVENTS  error  METHODS  again  detect  io  is_running  next_tick  one_tick  recurring  remove  reset  start  stop  timer  watch  SEE ALSO 

NAME

Mojo::Reactor − Low−level event reactor base class

SYNOPSIS

package Mojo::Reactor::MyEventLoop;
use Mojo::Base 'Mojo::Reactor';
sub again {...}
sub io {...}
sub is_running {...}
sub next_tick {...}
sub one_tick {...}
sub recurring {...}
sub remove {...}
sub reset {...}
sub start {...}
sub stop {...}
sub timer {...}
sub watch {...}

DESCRIPTION

Mojo::Reactor is an abstract base class for low-level event reactors, like Mojo::Reactor::EV and Mojo::Reactor::Poll.

EVENTS

Mojo::Reactor inherits all events from Mojo::EventEmitter and can emit the following new ones.

error

$reactor−>on(error => sub ($reactor, $err) {...});

Emitted for exceptions caught in callbacks, fatal if unhandled. Note that if this event is unhandled or fails it might kill your program, so you need to be careful.

$reactor−>on(error => sub ($reactor, $err) { say "Something very bad happened: $err" });

METHODS

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

again

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

Restart timer and optionally change the invocation time. Meant to be overloaded in a subclass. Note that this method requires an active timer.

detect

my $class = Mojo::Reactor−>detect;

Detect and load the best reactor implementation available, will try the value of the "MOJO_REACTOR" environment variable, Mojo::Reactor::EV or Mojo::Reactor::Poll.

# Instantiate best reactor implementation available
my $reactor = Mojo::Reactor−>detect−>new;

io

$reactor = $reactor−>io($handle => sub {...});

Watch handle for I/O events, invoking the callback whenever handle becomes readable or writable. Meant to be overloaded in a subclass.

# Callback will be executed twice if handle becomes readable and writable
$reactor−>io($handle => sub ($reactor, $writable) {
say $writable ? 'Handle is writable' : 'Handle is readable';
});

is_running

my $bool = $reactor−>is_running;

Check if reactor is running. Meant to be overloaded in a subclass.

next_tick

my $undef = $reactor−>next_tick(sub {...});

Execute callback as soon as possible, but not before returning or other callbacks that have been registered with this method, always returns "undef". Meant to be overloaded in a subclass.

one_tick

$reactor−>one_tick;

Run reactor until an event occurs. Note that this method can recurse back into the reactor, so you need to be careful. Meant to be overloaded in a subclass.

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

recurring

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

Create a new recurring timer, invoking the callback repeatedly after a given amount of time in seconds. Meant to be overloaded in a subclass.

remove

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

Remove handle or timer. Meant to be overloaded in a subclass.

reset

$reactor−>reset;

Remove all handles and timers. Meant to be overloaded in a subclass.

start

$reactor−>start;

Start watching for I/O and timer events, this will block until "stop" is called. Note that some reactors stop automatically if there are no events being watched anymore. Meant to be overloaded in a subclass.

# Start reactor only if it is not running already
$reactor−>start unless $reactor−>is_running;

stop

$reactor−>stop;

Stop watching for I/O and timer events. Meant to be overloaded in a subclass.

timer

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

Create a new timer, invoking the callback after a given amount of time in seconds. Meant to be overloaded in a subclass.

watch

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

Change I/O events to watch handle for with true and false values. Meant to be overloaded in a subclass. 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);

SEE ALSO

Mojolicious, Mojolicious::Guides, <https://mojolicious.org>.


Updated 2024-01-29 - jenkler.se | uex.se