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 / 
Parallol-0.1
River stage zero No dependents
3 ++
/ Mojolicious::Plugin::Parallol

NAME

Mojolicious::Plugin::Parallol - Because parallel requests should be as fun as parallololololol!

SYNOPSIS

  # Mojolicious
  $self->plugin('Parallol');

  # Mojolicious::Lite
  plugin 'Parallol';

DESCRIPTION

Mojolicious::Plugin::Parallol provides a simple helper for managing several parallel requests in the controller.

HELPERS

Mojolicious::Plugin::Parallol implements the following helpers.

parallol

Parallol optimizes for the common case: You want to call several parallel requests and render the view when they're done.

  get '/' => sub {
    my $self = shift;

    $self->ua->get('http://bbc.co.uk/', $self->parallol(sub {
      $self->stash(bbc => pop->res->dom->at('title')->text);
    }));

    $self->ua->get('http://mojolicio.us/', $self->parallol(sub {
      $self->stash(mojo => pop->res->dom->at('title')->text);
    }));
  };

By wrapping a callback in $self->parallol you mark the current response as asynchronous (see "render_later" in Mojolicious::Controller) and Parallol will render the view when all callbacks are called.

Automatic stashing

By passing a string to $self->parallol it will stash the last argument of the result instead. If we rewrite the previous example to use a helper, we can simplify our controller quite a lot.

  get '/' => sub {
    my $self = shift;

    $self->title('http://bbc.co.uk/',    $self->parallol('bbc'));
    $self->title('http://mojolicio.us/', $self->parallol('mojo'));
  };

  helpers title => sub {
    my ($self, $url, $cb) = @_;
    $self->ua->get($url, sub {
      $cb->(pop->res->dom->at('title')->text);
    });
  };

It's recommended that you move as much logic to helpers and other classes/methods so you can take advantage of automatic stashing.

Overriding "done" behavior

When you need to do more than just rendering the view you can override the "done" callback:

  get '/' => sub {
    my $self = shift;
    $self->on_parallol(sub {
      shift->render(template => 'something_else');
    });
  };

$self weakening

In order to prevent memory leaks, Parallol will automatically weaken $self. This means that if you don't refer to $self in your callback objects will magically disappear.

  # This controller will behave very strangely:
  get '/' => sub {
    my $self = shift;
    my $res = {};
    $self->ua->get('http://bbc.co.uk/', $self->parallol(sub {
      # There's no reference to $self in this block
      $res->{bbc} = pop->res->dom->at('title')->text;
    }));
  };

In these cases you can disabled weakening by passing in weaken => 0.

  # This controller is fine:
  get '/' => sub {
    my $self = shift;
    my $res = {};
    $self->ua->get('http://bbc.co.uk/', $self->parallol(weaken => 0, sub {
      # There's no reference to $self in this block
      $res->{bbc} = pop->res->dom->at('title')->text;
    }));
  };

METHODS

Mojolicious::Plugin::Parrallol inherits all methods from Mojolicious::Plugin and implements the following new ones.

register

  $plugin->register;

Register helpers in Mojolicious application.

SEE ALSO

Mojolicious, Parallol

AUTHOR

Magnus Holm mailto:magnus@nordaaker.com

LICENSE

This software is licensed under the same terms as Perl itself.