Net::DBus::Error - Error details for remote method invocation
package Music::Player::UnknownFormat;
use base qw(Net::DBus::Error);
# Define an error type for unknown track encoding type
# for a music player service
sub new {
my $proto = shift;
my $class = ref($proto) || $proto;
my $self = $class->SUPER::new(name => "org.example.music.UnknownFormat",
message => "Unknown track encoding format");
}
package Music::Player::Engine;
...snip...
# Play either mp3 or ogg music tracks, otherwise
# thrown an error
sub play {
my $self = shift;
my $url = shift;
if ($url =~ /\.(mp3|ogg)$/) {
...play the track
} else {
die Music::Player::UnknownFormat->new();
}
}
This objects provides for strongly typed error handling. Normally a service
would simply call
die "some message text"
When returning the error condition to the calling DBus client, the
message is associated with a generic error code or
"org.freedesktop.DBus.Failed". While this suffices for many
applications, occasionally it is desirable to be able to catch and handle
specific error conditions. For such scenarios the service should create
subclasses of the "Net::DBus::Error"
object providing in a custom error name. This error name is then sent back
to the client instead of the genreic "org.freedesktop.DBus.Failed"
code.
- my $error = Net::DBus::Error->new(name => $error_name, message =>
$description);
- Creates a new error object whose name is given by the
"name" parameter, and long descriptive
text is provided by the "message"
parameter. The "name" parameter has
certain formatting rules which must be adhered to. It must only contain
the letters 'a'-'Z', '0'-'9', '-', '_' and '.'. There must be at least two
components separated by a '.', For example a valid name is
'org.example.Music.UnknownFormat'.
- $error->name
- Returns the DBus error name associated with the object.
- $error->message
- Returns the descriptive text/message associated with the error
condition.
- $error->stringify
- Formats the error as a string in a manner suitable for printing out /
logging / displaying to the user, etc.
Copyright (C) 2005-2011 Daniel P. Berrange
Net::DBus, Net::DBus::Object