Net::DBus::BaseObject(User Contributed Perl DocumentNet::DBus::BaseObject(3pm)NAMENet::DBus::BaseObject - base class for exporting objects to the bus
SYNOPSIS
# We're going to be a DBus object
use base qw(Net::DBus::BaseObject);
# 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 _dispatch_object {
my $self = shift;
my $connection = shift;
my $message = shift;
if (....$message refers to a object's method ... ) {
...dispatch this object's interfaces/methods...
return $reply;
}
}
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, the "_dispatch"
object should be implemented to handle processing of incoming messages.
The Net::DBus::Exporter module is used to declare which methods (and
signals) are being exported 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.
Application developers will rarely want to use this class directly,
instead either Net::DBus::Object or "Net::DBus::ProxyObject" are the
common choices. This class will only be used if wanting to write a new
approach to dispatching incoming method calls.
METHODS
my $object = Net::DBus::BaseObject->new($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 the "export_service"
method on the Net::DBus object.
my $object = Net::DBus::BaseObject->new($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::BaseObject.
$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 the "dbus_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 the "dbus_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 the "dbus_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.
$reply = $object->_dispatch_object($connection, $message);
The "_dispatch_object" method is to be used to handle dispatch of
methods implemented by the object. The default implementation is a
no-op and should be overridden by subclasses todo whatever
processing is required. If the $message could be handled then
another "Net::DBus::Binding::Message" instance should be returned
for the reply. If "undef" is returned, then a generic error will be
returned to the caller.
$currvalue = $object->_dispatch_property($name); =item
$object->_dispatch_property($name, $newvalue);
The "_dispatch_property" method is to be used to handle dispatch of
property reads and writes. The $name parameter is the name of the
property being accessed. If $newvalue is supplied then the property
is to be updated, otherwise the current value is to be returned.
The default implementation will simply raise an error, so must be
overridden in subclasses.
AUTHOR
Daniel P. Berrange
COPYRIGHT
Copyright (C) 2005-2011 Daniel P. Berrange
SEE ALSO
Net::DBus, Net::DBus::Service, Net::DBus::Object,
Net::DBus::ProxyObject, Net::DBus::Exporter, Net::DBus::RemoteObject
perl v5.26.0 2017-07-22 Net::DBus::BaseObject(3pm)
