TABLE OF CONTENTS

NAME

Mojo::IOLoop::Delay - 管理回调和控制事件流顺序

SYNOPSIS

use Mojo::IOLoop::Delay;

# 同步多个事件
my $delay = Mojo::IOLoop::Delay->new;
$delay->on(finish => sub { say 'BOOM!' });
for my $i (1 .. 10) {
  my $end = $delay->begin;
  Mojo::IOLoop->timer($i => sub {
    say 10 - $i;
    $end->();
  });
}
$delay->wait unless Mojo::IOLoop->is_running;

# 顺序化多个事件
my $delay = Mojo::IOLoop::Delay->new;
$delay->steps(

  # First step (simple timer)
  sub {
    my $delay = shift;
    Mojo::IOLoop->timer(2 => $delay->begin);
    say 'Second step in 2 seconds.';
  },

  # Second step (parallel timers)
  sub {
    my ($delay, @args) = @_;
    Mojo::IOLoop->timer(1 => $delay->begin);
    Mojo::IOLoop->timer(3 => $delay->begin);
    say 'Third step in 3 seconds.';
  },

  # Third step (the end)
  sub {
    my ($delay, @args) = @_;
    say 'And done after 5 seconds total.';
  }
);
$delay->wait unless Mojo::IOLoop->is_running;

DESCRIPTION

Mojo::IOLoop::Delay manages callbacks and controls the flow of events for Mojo::IOLoop.

EVENTS

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

error

$delay->on(error => sub {
  my ($delay, $err) = @_;
  ...
});

Emitted if an error occurs in one of the steps, breaking the chain.

finish

$delay->on(finish => sub {
  my ($delay, @args) = @_;
  ...
});

Emitted once the active event counter reaches zero and there are no more steps.

ATTRIBUTES

Mojo::IOLoop::Delay implements the following attributes.

ioloop

my $ioloop = $delay->ioloop;
$delay     = $delay->ioloop(Mojo::IOLoop->new);

Event loop object to control, defaults to the global Mojo::IOLoop singleton.

METHODS

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

begin

my $without_first_arg = $delay->begin;
my $with_first_arg    = $delay->begin(0);

Increment active event counter, the returned callback can be used to decrement the active event counter again. Arguments passed to the callback are queued in the right order for the next step or finish event and wait method, the first argument will be ignored by default.

# Capture all arguments
my $delay = Mojo::IOLoop->delay;
Mojo::IOLoop->client({port => 3000} => $delay->begin(0));
my ($loop, $err, $stream) = $delay->wait;

steps

$delay = $delay->steps(sub {...}, sub {...});

Sequentialize multiple events, the first callback will run right away, and the next one once the active event counter reaches zero. This chain will continue until there are no more callbacks, a callback does not increment the active event counter or an error occurs in a callback.

wait

my $arg  = $delay->wait;
my @args = $delay->wait;

Start ioloop and stop it again once an error or finish event gets emitted, only works when ioloop is not running already.

# Use the "finish" event to synchronize portably
$delay->on(finish => sub {
  my ($delay, @args) = @_;
  ...
});
$delay->wait unless $delay->ioloop->is_running;

SEE ALSO

Mojolicious, Mojolicious::Guides, http://mojolicio.us.