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>