Net::DBus::ProxyObject

Section: User Contributed Perl Documentation (3)
Updated: 2021-01-27
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NAME

Net::DBus::ProxyObject - Implement objects to export to the bus

SYNOPSIS

  # Connecting an object to the bus, under a service
  package main;

  use Net::DBus;

  # Attach to the bus
  my $bus = Net::DBus->find;

  # Create our application's object instance
  my $object = Demo::HelloWorld->new()

  # Acquire a service 'org.demo.Hello'
  my $service = $bus->export_service("org.demo.Hello");

  # Finally export the object to the bus
  my $proxy = Demo::HelloWorld::DBus->new($object);

  ....rest of program...


  # Define a new package for the object we're going
  # to export
  package Demo::HelloWorld;

  sub new {
      my $class = shift;
      my $service = shift;
      my $self = {};

      $self->{sighandler} = undef;

      bless $self, $class;

      return $self;
  }

  sub sighandler {
      my $self = shift;
      my $callback = shift;

      $self->[sighandler} = $callback;
  }

  sub Hello {
    my $self = shift;
    my $name = shift;

    &{$self->{sighandler}}("Greeting", "Hello $name");
    return "Said hello to $name";
  }

  sub Goodbye {
    my $self = shift;
    my $name = shift;

    &{$self->{sighandler}}("Greeting", "Goodbye $name");
    return "Said goodbye to $name";
  }


  # Define a new package for the object we're going
  # to export
  package Demo::HelloWorld::DBus;

  # Specify the main interface provided by our object
  use Net::DBus::Exporter qw(org.example.demo.Greeter);

  # We're going to be a DBus object
  use base qw(Net::DBus::ProxyObject);

  # Export a 'Greeting' signal taking a stringl string parameter
  dbus_signal("Greeting", ["string"]);

  # Export 'Hello' as a method accepting a single string
  # parameter, and returning a single string value
  dbus_method("Hello", ["string"], ["string"]);

  sub new {
      my $class = shift;
      my $service = shift;
      my $impl = shfit;
      my $self = $class->SUPER::new($service, "/org/demo/HelloWorld", $impl);

      bless $self, $class;

      $self->sighandler(sub {
          my $signame = shift;
          my $arg = shift;
          $self->emit_signal($signame, $arg);
      });

      return $self;
  }

  # Export 'Goodbye' as a method accepting a single string
  # parameter, and returning a single string, but put it
  # in the 'org.exaple.demo.Farewell' interface

  dbus_method("Goodbye", ["string"], ["string"], "org.example.demo.Farewell");

DESCRIPTION

This the base for creating a proxy between a bus object and an application's object. It allows the application's object model to remain separate from the RPC object model. The proxy object will forward method calls from the bus, to the implementation object. The proxy object can also register callbacks against the application object, which it can use to then emit signals on the bus.

METHODS

my $object = Net::DBus::ProxyObject->new($service, $path, $impl): This creates a new DBus object with an path of $path registered within the service $service. The $path parameter should be a string complying with the usual DBus requirements for object paths, while the $service parameter should be an instance of Net::DBus::Service. The latter is typically obtained by calling the "export_service" method on the Net::DBus object. The $impl parameter is the application object which will implement the methods being exported to the bus.
my $object = Net::DBus::ProxyObject->new($parentobj, $subpath, $impl): This creates a new DBus child object with an path of $subpath relative to its parent $parentobj. The $subpath parameter should be a string complying with the usual DBus requirements for object paths, while the $parentobj parameter should be an instance of Net::DBus::BaseObject or a subclass. The $impl parameter is the application object which will implement the methods being exported to the bus.

AUTHOR

Daniel P. Berrange

Net::DBus::ProxyObject

NAME

SYNOPSIS

DESCRIPTION

METHODS

AUTHOR

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