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NAME

ZMQ::FFI - zeromq bindings using libffi and FFI::Raw

VERSION

version 0.09

SYNOPSIS

    #### send/recv ####

    use v5.10;
    use ZMQ::FFI;
    use ZMQ::FFI::Constants qw(ZMQ_REQ ZMQ_REP);

    my $endpoint = "ipc://zmq-ffi-$$";
    my $ctx      = ZMQ::FFI->new( threads => 1 );

    my $s1 = $ctx->socket(ZMQ_REQ);
    $s1->connect($endpoint);

    my $s2 = $ctx->socket(ZMQ_REP);
    $s2->bind($endpoint);

    $s1->send('ohhai');

    say $s2->recv();
    # ohhai


    #### pub/sub ####

    use v5.10;
    use ZMQ::FFI;
    use ZMQ::FFI::Constants qw(ZMQ_PUB ZMQ_SUB);
    use Time::HiRes q(usleep);

    my $endpoint = "ipc://zmq-ffi-$$";
    my $ctx      = ZMQ::FFI->new();

    my $s = $ctx->socket(ZMQ_SUB);
    my $p = $ctx->socket(ZMQ_PUB);

    $s->connect($endpoint);
    $p->bind($endpoint);

    # all topics
    {
        $s->subscribe('');
        $p->send('ohhai');

        until ($s->has_pollin) {
            # compensate for slow subscriber
            usleep 100_000;
            $p->send('ohhai');
        }

        say $s->recv();
        # ohhai

        $s->unsubscribe('');
    }

    # specific topics
    {
        $s->subscribe('topic1');
        $s->subscribe('topic2');

        $p->send('topic1 ohhai');
        $p->send('topic2 ohhai');

        until ($s->has_pollin) {
            usleep 100_000;
            $p->send('topic1 ohhai');
            $p->send('topic2 ohhai');
        }

        while ($s->has_pollin) {
            say join ' ', $s->recv();
            # topic1 ohhai
            # topic2 ohhai
        }
    }


    #### multipart ####

    use v5.10;
    use ZMQ::FFI;
    use ZMQ::FFI::Constants qw(ZMQ_DEALER ZMQ_ROUTER);

    my $endpoint = "ipc://zmq-ffi-$$";
    my $ctx      = ZMQ::FFI->new();

    my $d = $ctx->socket(ZMQ_DEALER);
    $d->set_identity('dealer');

    my $r = $ctx->socket(ZMQ_ROUTER);

    $d->connect($endpoint);
    $r->bind($endpoint);

    $d->send_multipart([qw(ABC DEF GHI)]);

    say join ' ', $r->recv_multipart;
    # dealer ABC DEF GHI


    #### nonblocking ####

    use v5.10;
    use ZMQ::FFI;
    use ZMQ::FFI::Constants qw(ZMQ_PUSH ZMQ_PULL);
    use AnyEvent;
    use EV;

    my $endpoint = "ipc://zmq-ffi-$$";
    my $ctx      = ZMQ::FFI->new();
    my @messages = qw(foo bar baz);


    my $pull = $ctx->socket(ZMQ_PULL);
    $pull->bind($endpoint);

    my $fd = $pull->get_fd();

    my $recv = 0;
    my $w = AE::io $fd, 0, sub {
        while ( $pull->has_pollin ) {
            say $pull->recv();
            # foo, bar, baz

            $recv++;
            if ($recv == 3) {
                EV::unloop();
            }
        }
    };


    my $push = $ctx->socket(ZMQ_PUSH);
    $push->connect($endpoint);

    my $sent = 0;
    my $t;
    $t = AE::timer 0, .1, sub {
        $push->send($messages[$sent]);

        $sent++;
        if ($sent == 3) {
            undef $t;
        }
    };

    EV::run();


    #### specifying versions ####

    use ZMQ::FFI;

    # 2.x context
    my $ctx = ZMQ::FFI->new( soname => 'libzmq.so.1' );
    my ($major, $minor, $patch) = $ctx->version;

    # 3.x context
    my $ctx = ZMQ::FFI->new( soname => 'libzmq.so.3' );
    my ($major, $minor, $patch) = $ctx->version;

DESCRIPTION

ZMQ::FFI exposes a high level, transparent, OO interface to zeromq independent of the underlying libzmq version. Where semantics differ, it will dispatch to the appropriate backend for you. As it uses ffi, there is no dependency on XS or compilation.

CONTEXT API

new([threads, max_sockets, soname])

    ZMQ::FFI->new( threads => 42, max_sockets => 42 )

returns a new context object, appropriate for the version of libzmq found on your system. It accepts the following optional attributes:

threads

zeromq thread pool size. Default: 1

max_sockets

only for zeromq 3.x

max number of sockets allowed for context. Default: 1024

soname

specify the libzmq library name to load. By default ZMQ::FFI will try the linker name, libzmq.so, and then the sonames libzmq.so.3 and libzmq.so.1, in that order. soname can also be the path to a particular libzmq so file

It is technically possible to have multiple contexts of different versions in the same process, though the utility of doing such a thing is dubious

($major, $minor, $patch) = version()

return the libzmq version as the list ($major, $minor, $patch)

get($option)

only for zeromq 3.x

    $ctx->get(ZMQ_IO_THREADS)

get a context option value

set($option, $option_value)

only for zeromq 3.x

    $ctx->set(ZMQ_MAX_SOCKETS, 42)

set a context option value

socket($type)

    $ctx->socket(ZMQ_REQ)

returns a socket of the specified type. See "SOCKET API" below

destroy()

destroys the underlying zmq context. This is called automatically when the object gets reaped

SOCKET API

The following API is available on socket objects created by $ctx->socket.

For core attributes and functions, common across all versions of zeromq, convenience methods are provided. Otherwise, generic get/set methods are provided that will work independent of version.

As attributes are constantly being added/removed from zeromq, it is unlikely the 'static' accessors will grow much beyond the current set.

($major, $minor, $patch) = version()

same as Context version() above

connect($endpoint)

does socket connect on the specified endpoint

bind($endpoint)

does socket bind on the specified endpoint

get_linger(), set_linger($millis)

get or set the current socket linger period

get_identity(), set_identity($ident)

get or set the socket identity for request/reply patterns

get_fd()

get the file descriptor associated with the socket

subscribe($topic)

add $topic to the subscription list

unsubscribe($topic)

remove $topic from the subscription list

send($msg, [$flags])

    $socket->send('ohhai')

sends a message using the optional flags

send_multipart($parts_aref, [$flags])

    $socket->send([qw(foo bar baz)])

given an array ref of message parts, sends the multipart message using the optional flags. ZMQ_SNDMORE semantics are handled for you

recv([$flags])

receive a message

@parts = recv_multipart([$flags])

receives a multipart message, returning an array of parts. ZMQ_RCVMORE semantics are handled for you

has_pollin, has_pollout

checks ZMQ_EVENTS for ZMQ_POLLIN and ZMQ_POLLOUT respectively, and returns true/false depending on the state

get($option, $option_type)

    $socket->get(ZMQ_LINGER, 'int')

return the value for the specified socket option. $option_type is the type associated with the option value in the zeromq API (zmq_getsockopt man page)

set($option, $option_type, $option_value)

    $socket->set(ZMQ_IDENTITY, 'binary', 'foo')

set the socket option to the specified value. $option_type is the type associated with the option value in the zeromq API (zmq_setsockopt man page)

close()

close the underlying zmq socket. This is called automatically when the object gets reaped

ERROR HANDLING

ZMQ::FFI checks the return codes of underlying zmq functions for you, and in the case of an error it will die with the plain english system error message.

    $ctx->socket(-1);
    # dies with 'zmq_socket: Invalid argument'

SEE ALSO

AUTHOR

Dylan Cali <calid1984@gmail.com>

COPYRIGHT AND LICENSE

This software is copyright (c) 2014 by Dylan Cali.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.