NAME

Test::Stream::IPC - Base class for Test::Stream IPC drivers.

EXPERIMENTAL CODE WARNING

This is an experimental release! Test-Stream, and all its components are still in an experimental phase. This dist has been released to cpan in order to allow testers and early adopters the chance to write experimental new tools with it, or to add experimental support for it into old tools.

PLEASE DO NOT COMPLETELY CONVERT OLD TOOLS YET. This experimental release is very likely to see a lot of code churn. API's may break at any time. Test-Stream should NOT be depended on by any toolchain level tools until the experimental phase is over.

SYNOPSIS

    package Test::Stream::IPC::MyDriver;

    use base 'Test::Stream::IPC';

    ...

CLASS METHODS

@drivers = $class->drivers

Obtain the list of drivers that have been registered, in the order they were registered. If no driver has been loaded this will load, register, and return Test::Stream::IPC::Files.

$class->register_driver($DRIVER)

This is an alias to register_driver

$class->register_drivers($DRIVER1, $DRIVER2)

Use this to register an IPC driver. The driver shoudl already be loaded.

$class->enable_polling

This turns on IPC polling. Essentially this adds a global callback on context initialization. Every time a context is obtained from Test::Stream::Context the IPC driver will have a chance to poll for pending events.

This can only be turned on once, and it can not be turned off. The effects are global.

INSTANCE METHODS

$self->abort($msg)

If an IPC encounters a fatal error it should use this. This will print the message to STDERR with 'IPC Fatal Error: ' prefixed to it, then it will forcefully exit 255. IPC errors may occur in threads or processes other than the main one, this method provides the best chance of the harness noticing the error.

$self->abort_trace($msg)

This is the same as $ipc->abort($msg) except that it uses Carp::longmess to add a stack trace to the message.

LOADING DRIVERS

Test::Stream::IPC has an import() method. All drivers inherit this import method. This import method registers the driver with the main IPC module.

In most cases you just need to load the desired IPC driver to make it work. You should load this driver as early as possible. A warning will be issued if you load it too late for it to be effective.

    use Test::Stream::IPC::MyDriver;
    ...

WRITING DRIVERS

    package Test::Stream::IPC::MyDriver;
    use strict;
    use warnings;

    use base 'Test::Stream::IPC';

    sub is_viable {
        return 0 if $^O eq 'win32'; # Will not work on windows.
        return 1;
    }

    sub add_hub {
        my $self = shift;
        my ($hid) = @_;

        ... # Make it possible to contact the hub
    }

    sub drop_hub {
        my $self = shift;
        my ($hid) = @_;

        ... # Nothing should try to reach the hub anymore.
    }

    sub send {
        my $self = shift;
        my ($hid, $e) = @_;

        ... # Send the event to the proper hub.
    }

    sub cull {
        my $self = shift;
        my ($hid) = @_;

        my @events = ...; # Here is where you get the events for the hub

        return @events;
    }

    sub waiting {
        my $self = shift;

        ... # Notify all listening procs and threads that the main
        ... # process/thread is waiting for them to finish.
    }

    1;

METHODS SUBCLASSES MUST IMPLEMENT

$ipc->is_viable

This should return true if the driver works in the current environment. This should return false if it does not. This is a CLASS method.

$ipc->add_hub($hid)

This is used to alert the driver that a new hub is expecting events. The driver should keep track of the process and thread ids, the hub should only be dropped by the proc+thread that started it.

    sub add_hub {
        my $self = shift;
        my ($hid) = @_;

        ... # Make it possible to contact the hub
    }

$ipc->drop_hub($hid)

This is used to alert the driver that a hub is no longer accepting events. The driver should keep track of the process and thread ids, the hub should only be dropped by the proc+thread that started it (This is the drivers responsibility to enforce).

    sub drop_hub {
        my $self = shift;
        my ($hid) = @_;

        ... # Nothing should try to reach the hub anymore.
    }

$ipc->send($hid, $event);

Used to send events from the current process/thread to the specified hub in its process+thread.

    sub send {
        my $self = shift;
        my ($hid, $e) = @_;

        ... # Send the event to the proper hub.
    }

@events = $ipc->cull($hid)

Used to collect events that have been sent to the specified hub.

    sub cull {
        my $self = shift;
        my ($hid) = @_;

        my @events = ...; # Here is where you get the events for the hub

        return @events;
    }

$ipc->waiting()

This is called in the parent process when it is complete and waiting for all child processes and threads to complete.

    sub waiting {
        my $self = shift;

        ... # Notify all listening procs and threads that the main
        ... # process/thread is waiting for them to finish.
    }

SOURCE

The source code repository for Test::Stream can be found at http://github.com/Test-More/Test-Stream/.

MAINTAINERS

Chad Granum <exodist@cpan.org>

AUTHORS

Chad Granum <exodist@cpan.org>

COPYRIGHT

Copyright 2015 Chad Granum <exodist7@gmail.com>.

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

See http://www.perl.com/perl/misc/Artistic.html