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);