NAME
IO::Async::Protocol::Stream
- base class for stream-based protocols
SYNOPSIS
Most likely this class will be subclassed to implement a particular network protocol.
package Net::Async::HelloWorld;
use strict;
use warnings;
use base qw( IO::Async::Protocol::Stream );
sub on_read
{
my $self = shift;
my ( $buffref, $eof ) = @_;
return 0 unless $$buffref =~ s/^(.*)\n//;
my $line = $1;
if( $line =~ m/^HELLO (.*)/ ) {
my $name = $1;
$self->invoke_event( on_hello => $name );
}
return 1;
}
sub send_hello
{
my $self = shift;
my ( $name ) = @_;
$self->write( "HELLO $name\n" );
}
This small example elides such details as error handling, which a real protocol implementation would be likely to contain.
DESCRIPTION
This subclass of IO::Async::Protocol is intended to stand as a base class for implementing stream-based protocols. It provides an interface similar to IO::Async::Stream, primarily, a write
method and an on_read
event handler.
It contains an instance of an IO::Async::Stream
object which it uses for actual communication, rather than being a subclass of it, allowing a level of independence from the actual stream being used. For example, the stream may actually be an IO::Async::SSLStream to allow the protocol to be used over SSL.
As with IO::Async::Stream
, it is required that by the time the protocol object is added to a Loop, that it either has an on_read
method, or has been configured with an on_read
callback handler.
EVENTS
The following events are invoked, either using subclass methods or CODE references in parameters:
$ret = on_read \$buffer, $eof
on_read_eof
on_write_eof
The event handlers are invoked identically to IO::Async::Stream
.
on_closed
The on_closed
handler is optional, but if provided, will be invoked after the stream is closed by either side (either because the close()
method has been invoked on it, or on an incoming EOF).
PARAMETERS
The following named parameters may be passed to new
or configure
:
on_read => CODE
on_read_eof => CODE
on_write_eof => CODE
CODE references for the events.
handle => IO
A shortcut for the common case where the transport only needs to be a plain IO::Async::Stream
object. If this argument is provided without a transport
object, a new IO::Async::Stream
object will be built around the given IO handle, and used as the transport.
METHODS
$protocol->write( $data )
Writes the given data by calling the write
method on the contained transport stream.
$protocol->connect( %args )
Sets up a connection to a peer, and configures the underlying transport
for the Protocol. Calls IO::Async::Protocol
connect
with socktype
set to "stream"
.
AUTHOR
Paul Evans <leonerd@leonerd.org.uk>