NAME
Net::DBus::Object - Provide objects to the bus for clients to use
SYNOPSIS
# Connecting an object to the bus, under a service
package main;
use Net::DBus;
# Attach to the bus
my $bus = Net::DBus->find;
# Acquire a service 'org.demo.Hello'
my $service = $bus->export_service("org.demo.Hello");
# Export our object within the service
my $object = Demo::HelloWorld->new($service);
....rest of program...
# Define a new package for the object we're going
# to export
package Demo::HelloWorld;
# 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::Object);
# 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 $self = $class->SUPER::new($service, "/org/demo/HelloWorld");
bless $self, $class;
return $self;
}
sub Hello {
my $self = shift;
my $name = shift;
$self->emit_signal("Greeting", "Hello $name");
return "Said hello to $name";
}
# 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");
sub Goodbye {
my $self = shift;
my $name = shift;
$self->emit_signal("Greeting", "Goodbye $name");
return "Said goodbye to $name";
}
DESCRIPTION
This the base of all objects which are exported to the message bus. It provides the core support for type introspection required for objects exported to the message. When sub-classing this object, methods can be created & tested as per normal Perl modules. Then just as the Exporter module is used to export methods within a script, the Net::DBus::Exporter module is used to export methods (and signals) to the message bus.
All packages inheriting from this, will automatically have the interface org.freedesktop.DBus.Introspectable
registered with Net::DBus::Exporter, and the Introspect
method within this exported.
METHODS
- my $object = Net::DBus::Object->new($service, $path)
-
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 theexport_service
method on the Net::DBus object. - my $object = Net::DBus::Object->new($parentobj, $subpath)
-
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::Object. - $object->disconnect();
-
This method disconnects the object from the bus, such that it will no longer receive messages sent by other clients. Any child objects will be recursively disconnected too. After an object has been disconnected, it is possible for Perl to garbage collect the object instance. It will also make it possible to connect a newly created object to the same path.
- my $bool = $object->is_connected
-
Returns a true value if the object is connected to the bus, and thus capable of being accessed by remote clients. Returns false if the object is disconnected & thus ready for garbage collection. All objects start off in the connected state, and will only transition if the
disconnect
method is called. - my $service = $object->get_service
-
Retrieves the Net::DBus::Service object within which this object is exported.
- my $path = $object->get_object_path
-
Retrieves the path under which this object is exported
- $object->emit_signal_in($name, $interface, $client, @args);
-
Emits a signal from the object, with a name of
$name
. If the$interface
parameter is defined, the signal will be scoped within that interface. If the$client
parameter is defined, the signal will be unicast to that client on the bus. The signal and the data types of the arguments@args
must have been registered with Net::DBus::Exporter by calling thedbus_signal
method. - $self->emit_signal_to($name, $client, @args);
-
Emits a signal from the object, with a name of
$name
. The signal and the data types of the arguments@args
must have been registered with Net::DBus::Exporter by calling thedbus_signal
method. The signal will be sent only to the client named by the$client
parameter. - $self->emit_signal($name, @args);
-
Emits a signal from the object, with a name of
$name
. The signal and the data types of the arguments@args
must have been registered with Net::DBus::Exporter by calling thedbus_signal
method. The signal will be broadcast to all clients on the bus. - $object->connect_to_signal_in($name, $interface, $coderef);
-
Connects a callback to a signal emitted by the object. The
$name
parameter is the name of the signal within the object, and$coderef
is a reference to an anonymous subroutine. When the signal$name
is emitted by the remote object, the subroutine$coderef
will be invoked, and passed the parameters from the signal. The$interface
parameter is used to specify the explicit interface defining the signal to connect to. - $object->connect_to_signal($name, $coderef);
-
Connects a callback to a signal emitted by the object. The
$name
parameter is the name of the signal within the object, and$coderef
is a reference to an anonymous subroutine. When the signal$name
is emitted by the remote object, the subroutine$coderef
will be invoked, and passed the parameters from the signal.
AUTHOR
Daniel P. Berrange
COPYRIGHT
Copyright (C) 2005-2011 Daniel P. Berrange
SEE ALSO
Net::DBus, Net::DBus::Service, Net::DBus::RemoteObject, Net::DBus::Exporter.