package Business::PayPal::API;
$Business::PayPal::API::VERSION = '0.76';
use 5.008001;
use strict;
use warnings;
use Data::Printer;
use SOAP::Lite 0.67; # +trace => 'all';
use Carp qw(carp);
our $Debug = $ENV{WPP_DEBUG} || 0;
## NOTE: This package exists only until I can figure out how to use
## NOTE: SOAP::Lite's WSDL support for complex types and importing
## NOTE: type definitions, at which point this module will become much
## NOTE: smaller (or non-existent).
sub C_api_sandbox () { 'https://api.sandbox.paypal.com/2.0/' }
sub C_api_sandbox_3t () { 'https://api-3t.sandbox.paypal.com/2.0/' }
sub C_api_live () { 'https://api.paypal.com/2.0/' }
sub C_api_live_3t () { 'https://api-3t.paypal.com/2.0/' }
sub C_xmlns_pp () { 'urn:ebay:api:PayPalAPI' }
sub C_xmlns_ebay () { 'urn:ebay:apis:eBLBaseComponents' }
sub C_version () { '61.0' } ## 3.0 adds RecurringPayments
## this is an inside-out object. Make sure you 'delete' additional
## members in DESTROY() as you add them.
my %Soap;
my %Header;
my %H_PKCS12File; ## path to certificate file (pkc12)
my %H_PKCS12Password; ## password for certificate file (pkc12)
my %H_CertFile; ## PEM certificate
my %H_KeyFile; ## PEM private key
sub import {
my $self = shift;
my @modules = @_;
for my $module (@modules) {
eval("use Business::PayPal::API::$module;");
if ($@) {
warn $@;
next;
}
## import 'exported' subroutines into our namespace
no strict 'refs';
for my $sub (
@{ "Business::PayPal::API::" . $module . "::EXPORT_OK" } ) {
*{ "Business::PayPal::API::" . $sub }
= *{ "Business::PayPal::API::" . $module . "::" . $sub };
}
}
}
sub new {
my $class = shift;
my %args = @_;
my $self = bless \( my $fake ), $class;
## if you add new args, be sure to update the test file's @variables array
$args{Username} ||= '';
$args{Password} ||= '';
$args{Signature} ||= '';
$args{Subject} ||= '';
$args{sandbox} = 1 unless exists $args{sandbox};
$args{timeout} ||= 30;
$H_PKCS12File{$self} = $args{PKCS12File} || '';
$H_PKCS12Password{$self} = $args{PKCS12Password} || '';
$H_CertFile{$self} = $args{CertFile} || '';
$H_KeyFile{$self} = $args{KeyFile} || '';
my $proxy = (
$args{sandbox}
? (
$args{Signature}
? C_api_sandbox_3t
: C_api_sandbox
)
: (
$args{Signature}
? C_api_live_3t
: C_api_live
)
);
$Soap{$self} = SOAP::Lite->proxy(
$proxy,
timeout => $args{timeout},
(
exists $args{proxy_url}
? ( proxy => [ [ 'http', 'https' ] => $args{proxy_url} ] )
: ()
)
)->uri(C_xmlns_pp);
$Header{$self} = SOAP::Header->name(
RequesterCredentials => \SOAP::Header->value(
SOAP::Data->name(
Credentials => \SOAP::Data->value(
SOAP::Data->name( Username => $args{Username} )->type(''),
SOAP::Data->name( Password => $args{Password} )->type(''),
SOAP::Data->name( Signature => $args{Signature} )
->type(''),
SOAP::Data->name( Subject => $args{Subject} )->type(''),
),
)->attr( { xmlns => C_xmlns_ebay } )
)
)->attr( { xmlns => C_xmlns_pp } )->mustUnderstand(1);
return $self;
}
sub DESTROY {
my $self = $_[0];
delete $Soap{$self};
delete $Header{$self};
delete $H_PKCS12File{$self};
delete $H_PKCS12Password{$self};
delete $H_CertFile{$self};
delete $H_KeyFile{$self};
my $super = $self->can("SUPER::DESTROY");
goto &$super if $super;
}
sub version_req {
return SOAP::Data->name( Version => C_version )->type('xs:string')
->attr( { xmlns => C_xmlns_ebay } );
}
sub doCall {
my $self = shift;
my $method_name = shift;
my $request = shift;
my $method
= SOAP::Data->name($method_name)->attr( { xmlns => C_xmlns_pp } );
my $som;
{
$H_PKCS12File{$self}
and local $ENV{HTTPS_PKCS12_FILE} = $H_PKCS12File{$self};
$H_PKCS12Password{$self}
and local $ENV{HTTPS_PKCS12_PASSWORD} = $H_PKCS12Password{$self};
$H_CertFile{$self}
and local $ENV{HTTPS_CERT_FILE} = $H_CertFile{$self};
$H_KeyFile{$self} and local $ENV{HTTPS_KEY_FILE} = $H_KeyFile{$self};
if ($Debug) {
print STDERR SOAP::Serializer->envelope(
method => $method,
$Header{$self}, $request
),
"\n";
}
no warnings 'redefine';
local *SOAP::Deserializer::typecast = sub { shift; return shift };
eval {
$som = $Soap{$self}->call( $Header{$self}, $method => $request );
};
if ($@) {
carp $@;
return;
}
}
if ($Debug) {
## FIXME: would be nicer to dump a SOM to XML, but how to do that?
p( $som->envelope );
}
if ( ref($som) && $som->fault ) {
carp "Fault: "
. $som->faultstring
. ( $som->faultdetail ? " (" . $som->faultdetail . ")" : '' )
. "\n";
return;
}
return $som;
}
sub getFieldsList {
my $self = shift;
my $som = shift;
my $path = shift;
my $fields = shift;
return unless $som;
my %trans_id = ();
my @records = ();
for my $rec ( $som->valueof($path) ) {
my %response = ();
@response{ keys %$fields } = @{$rec}{ keys %$fields };
## avoid duplicates
if ( defined $response{TransactionID} ) {
if ( $trans_id{ $response{TransactionID} } ) {
next;
}
else {
$trans_id{ $response{TransactionID} } = 1;
}
}
push @records, \%response;
}
return \@records;
}
sub getFields {
my $self = shift;
my $som = shift;
my $path = shift;
my $response = shift;
my $fields = shift;
return unless $som;
## kudos to Erik Aronesty via email, Drew Simpson via rt.cpan.org (#28596)
## Erik wrote:
## <snip>
## If you want me to write the code for the "flagged" version, i
## can .. i think the '/@' flag is a pretty safe, and obvious flag.
##
## the advantage of the flagged version would be that the caller
## doesn't have to check the returned value ... in the case of a
## field where multiple values are expected.
## </snip>
##
## I agree with this on principle and would prefer it, but I voted
## against a special flag, now forcing the caller to check the
## return value, but only for the sake of keeping everything
## consistent with the rest of the API. If Danny Hembree wants to
## go through and implement Erik's suggestion, I'd be in favor of
## it.
for my $field ( keys %$fields ) {
my @vals = grep { defined } $som->valueof("$path/$fields->{$field}");
next unless @vals;
if ( scalar(@vals) == 1 ) {
$response->{$field} = $vals[0];
}
else {
$response->{$field} = \@vals;
}
}
}
sub getBasic {
my $self = shift;
my $som = shift;
my $path = shift;
my $details = shift;
return unless $som;
for my $field (qw( Ack Timestamp CorrelationID Version Build )) {
$details->{$field} = $som->valueof("$path/$field") || '';
}
return $details->{Ack} =~ /Success/;
}
sub getErrors {
my $self = shift;
my $som = shift;
my $path = shift;
my $details = shift;
return unless $som;
my @errors = ();
for my $enode ( $som->valueof("$path/Errors") ) {
push @errors,
{
LongMessage => $enode->{LongMessage},
ErrorCode => $enode->{ErrorCode},
};
}
$details->{Errors} = \@errors;
return;
}
1;
# ABSTRACT: PayPal SOAP API client with sandbox support
__END__
=pod
=encoding UTF-8
=head1 NAME
Business::PayPal::API - PayPal SOAP API client with sandbox support
=head1 VERSION
version 0.76
=head1 SYNOPSIS
use Business::PayPal::API qw( ExpressCheckout GetTransactionDetails );
## certificate authentication
my $pp = Business::PayPal::API->new(
Username => 'my_api1.domain.tld',
Password => 'this_is_my_password',
PKCS12File => '/path/to/cert.pkcs12',
PKCS12Password => '(pkcs12 password)',
sandbox => 1,
);
## PEM cert authentication
my $pp = Business::PayPal::API->new(
Username => 'my_api1.domain.tld',
Password => 'this_is_my_password',
CertFile => '/path/to/cert.pem',
KeyFile => '/path/to/cert.pem',
sandbox => 1,
);
## 3-token (Signature) authentication
my $pp = Business::PayPal::API->new(
Username => 'my_api1.domain.tld',
Password => 'Xdkis9k3jDFk39fj29sD9', ## supplied by PayPal
Signature =>
'f7d03YCpEjIF3s9Dk23F2V1C1vbYYR3ALqc7jm0UrCcYm-3ksdiDwjfSeii', ## ditto
sandbox => 1,
);
my %response = $pp->SetExpressCheckout( ... );
=head1 DESCRIPTION
B<Business::PayPal::API> supports both certificate authentication and
the new 3-token "Signature" authentication.
It also supports PayPal's development I<sandbox> for testing. See the
B<sandbox> parameter to B<new()> below for details.
B<Business::PayPal::API> can import other B<API> derived classes:
use Business::PayPal::API qw( RefundTransaction );
This allows for much more concise and intuitive usage. For example,
these two statements are equivalent:
use Business::PayPal::API::RefundTransaction;
my $pp = Business::PayPal::API::RefundTransaction->new( ... );
$pp->RefundTransaction( ... );
and more concisely:
use Business::PayPal::API qw( RefundTransaction );
my $pp = Business::PayPal::API->new( ... );
$pp->RefundTransaction( ... );
The advantage of this becomes clear when you need to use multiple API
calls in your program; this allows you to use the same object to
invoke the various methods, instead of creating a new object for each
subclass. Here is an example of a B<API> object used to invoke various
PayPal APIs with the same object:
use Business::PayPal::API qw( GetTransactionDetails
TransactionSearch
RefundTransaction );
my $pp = Business::PayPal::API->new( ... );
my $records = $pp->TransactionSearch( ... );
my %details = $pp->GetTransactionDetails( ... );
my %resp = $pp->RefundTransaction( ... );
However, you may certainly use just the subclass if that's all you
need. Every subclass should work as its own self-contained API.
For details on B<Business::PayPal::API::*> subclasses, see each
subclass's individual documentation.
=head2 new
Creates a new B<Business::PayPal::API> object.
A note about certificate authentication: PayPal (and this module)
support either PKCS#12 certificate authentication or PEM certificate
authentication. See options below.
=over 4
=item B<Username>
Required. This is the PayPal API username, usually in the form of
'my_api1.mydomain.tld'. You can find or create your API credentials by
logging into PayPal (if you want to do testing, as you should, you
should also create a developer sandbox account) and going to:
My Account -> Profile -> API Access -> Request API Credentials
Please see the I<PayPal API Reference> and I<PayPal Sandbox User
Guide> for details on creating a PayPal business account and sandbox
account for testing.
=item B<Password>
Required. If you use certificate authentication, this is the PayPal
API password created when you setup your certificate. If you use
3-token (Signature) authentication, this is the password PayPal
assigned you, along with the "API User Name" and "Signature Hash".
=item B<Subject>
Optional. This is used by PayPal to authenticate 3rd party billers
using your account. See the documents in L<SEE ALSO>.
=item B<Signature>
Required for 3-token (Signature) authentication. This is the
"Signature Hash" you received when you did "Request API Credentials"
in your PayPal Business Account.
=item B<PKCS12File>
Required for PKCS#12 certificate authentication, unless the
B<HTTPS_PKCS12_FILE> environment variable is already set.
This contains the path to your private key for PayPal
authentication. It is used to set the B<HTTPS_PKCS12_FILE> environment
variable. You may set this environment variable yourself and leave
this field blank.
=item B<PKCS12Password>
Required for PKCS#12 certificate authentication, unless the
B<HTTPS_PKCS12_PASSWORD> environment variable is already set.
This contains the PKCS#12 password for the key specified in
B<PKCS12File>. It is used to set the B<HTTPS_PKCS12_PASSWORD>
environment variable. You may set this environment variable yourself
and leave this field blank.
=item B<CertFile>
Required for PEM certificate authentication, unless the
HTTPS_CERT_FILE environment variable is already set.
This contains the path to your PEM format certificate given to you
from PayPal (and accessible in the same location that your Username
and Password and/or Signature Hash are found) and is used to set the
B<HTTPS_CERT_FILE> environment variable. You may set this environment
variable yourself and leave this field blank.
You may combine both certificate and private key into one file and set
B<CertFile> and B<KeyFile> to the same path.
=item B<KeyFile>
Required for PEM certificate authentication, unless the HTTPS_KEY_FILE
environment variable is already set.
This contains the path to your PEM format private key given to you
from PayPal (and accessible in the same location that your Username
and Password and/or Signature Hash are found) and is used to set the
B<HTTPS_KEY_FILE> environment variable. You may set this environment
variable yourself and leave this field blank.
You may combine both certificate and private key into one file and set
B<CertFile> and B<KeyFile> to the same path.
=item B<sandbox>
Required. If set to true (default), B<Business::PayPal::API> will
connect to PayPal's development sandbox, instead of PayPal's live
site. *You must explicitly set this to false (0) to access PayPal's
live site*.
If you use PayPal's development sandbox for testing, you must have
already signed up as a PayPal developer and created a Business sandbox
account and a Buyer sandbox account (and make sure both of them have
B<Verified> status in the sandbox).
When testing with the sandbox, you will use different usernames,
passwords, and certificates (if using certificate authentication) than
you will when accessing PayPal's live site. Please see the PayPal
documentation for details. See L<SEE ALSO> for references.
PayPal's sandbox reference:
L<https://www.paypal.com/IntegrationCenter/ic_sandbox.html>
=back
=item B<proxy_url>
Optional. When set, the proxy at the specified URL will be used for outbound
connections.
=item B<timeout>
Optional. Set the timeout in seconds. Defaults to 30 seconds.
=head1 NAME
Business::PayPal::API - PayPal API
=head1 ERROR HANDLING
Every API call should return an B<Ack> response, whether I<Success>,
I<Failure>, or otherwise (depending on the API call). If it returns
any non-success value, you can find an I<Errors> entry in your return
hash, whose value is an arrayref of hashrefs:
[ { ErrorCode => 10002,
LongMessage => "Invalid security header" },
{ ErrorCode => 10030,
LongMessage => "Some other error" }, ]
You can retrieve these errors like this:
%response = $pp->doSomeAPICall();
if( $response{Ack} ne 'Success' ) {
for my $err ( @{$response{Errors}} ) {
warn "Error: " . $err->{LongMessage} . "\n";
}
}
=head1 TESTING
Testing the B<Business::PayPal::API::*> modules requires that you
create a file containing your PayPal Developer Sandbox authentication
credentials (e.g., API certificate authentication or 3-Token
authentication signature, etc.) and setting the B<WPP_TEST>
environment variable to point to this file.
The format for this file is as follows:
Username = your_api.username.com
Password = your_api_password
and then ONE of the following options:
a) supply 3-token authentication signature
Signature = xxxxxxxxxxxxxxxxxxxxxxxx
b) supply PEM certificate credentials
CertFile = /path/to/cert_key_pem.txt
KeyFile = /path/to/cert_key_pem.txt
c) supply PKCS#12 certificate credentials
PKCS12File = /path/to/cert.p12
PKCS12Password = pkcs12_password
You may also set the appropriate HTTPS_* environment variables for b)
and c) above (e.g., HTTPS_CERT_FILE, HTTPS_KEY_FILE,
HTTPS_PKCS12_File, HTTPS_PKCS12_PASSWORD) in lieu of putting this
information in a file.
Then use "WPP_TEST=my_auth.txt make test" (for Bourne shell derivates) or
"setenv WPP_TEST my_auth.txt && make test" (for C-shell derivates).
See 'auth.sample.*' files in this package for an example of the file
format. Variables are case-*sensitive*.
Any of the following variables are recognized:
Username Password Signature Subject
CertFile KeyFile PKCS12File PKCS12Password
BuyerEmail
Note: PayPal authentication may I<fail> if you set the certificate
environment variables and attempt to connect using 3-token
authentication (i.e., PayPal will use the first authentication
credentials presented to it, and if they fail, the connection is
aborted).
=head1 TROUBLESHOOTING
=head2 PayPal Authentication Errors
If you are experiencing PayPal authentication errors (e.g., "Security
header is not valid", "SSL negotiation failed", etc.), you should make
sure:
* your username and password match those found in your PayPal
Business account sandbox (this is not the same as your regular
account).
* you're not trying to use your live username and password for
sandbox testing and vice versa.
* you are using a US Business Sandbox account, you may also need to have
"PayPal Payments Pro" enabled.
* if the sandbox works but "live" does not, make sure you've turned
off the 'sandbox' parameter correctly. Otherwise you'll be
passing your PayPal sandbox credentials to PayPal's live site
(which won't work).
* if you use certificate authentication, your certificate must be
the correct one (live or sandbox) depending on what you're doing.
* if you use 3-Token authentication (i.e., Signature), you don't
have any B<PKCS12*> parameters or B<CertFile> or B<KeyFile>
parameters in your constructor AND that none of the corresponding
B<HTTPS_*> environment variables are set. PayPal prefers
certificate authentication since it occurs at connection time; if
it fails, it will not try Signature authentication.
Try clearing your environment:
## delete all HTTPS, SSL env
delete $ENV{$_} for grep { /^(HTTPS|SSL)/ } keys %ENV;
## now put our own HTTPS env back in
$ENV{HTTPS_CERT_FILE} = '/var/path/to/cert.pem';
## create our paypal object
my $pp = Business::PayPal::API->new(...)
* if you have already loaded Net::SSLeay (or IO::Socket::SSL), then
Net::HTTPS will prefer to use IO::Socket::SSL. I don't know how
to get SOAP::Lite to work with IO::Socket::SSL (e.g.,
Crypt::SSLeay uses HTTPS_* environment variables), so until then,
you can use this hack:
local $IO::Socket::SSL::VERSION = undef;
$pp->DoExpressCheckoutPayment(...);
This will tell Net::HTTPS to ignore the fact that IO::Socket::SSL
is already loaded for this scope and import Net::SSL (part of the
Crypt::SSLeay package) for its 'configure()' method.
* if you receive a message like "500 Can't connect to
api.sandbox.paypal.com:443 (Illegal seek)", you'll need to make
sure you have Crypt::SSLeay installed. It seems that other crypto
modules don't do the certificate authentication quite as well,
and LWP needs this to negotiate the SSL connection with PayPal.
See the DEBUGGING section below for further hints.
=head2 PayPal Munging URLs
PayPal seems to be munging my URLs when it returns.
SOAP::Lite follows the XML specification carefully, and encodes '&'
and '<' characters before applying them to the SOAP document. PayPal
does not properly URL-decode HTML entities '&' and '<' on the
way back, so if you have an ampersand in your ReturnURL (for example),
your customers will be redirected here:
http://domain.tld/prog?arg1=foo&arg2=bar
instead of here:
http://domain.tld/prog?arg1=foo&arg2=bar
Solution:
Use CDATA tags to wrap your request:
ReturnURL => '<![CDATA[http://domain.tld/prog?arg1=foo&arg2=bar]]>'
You may also use semicolons instead of ampersands to separate your URL
arguments:
ReturnURL => 'http://domain.tld/prog?arg1=foo;arg2=bar'
(thanks to Ollie Ready)
=head1 DEBUGGING
You can see the raw SOAP XML sent and received by
B<Business::PayPal::API> by setting its B<$Debug> variable:
$Business::PayPal::API::Debug = 1;
$pp->SetExpressCheckout( %args );
this will print the XML being sent, and dump a Perl data structure of
the SOM received on STDERR (so check your error_log if running inside
a web server).
If anyone knows how to turn a SOAP::SOM object into XML without
setting B<outputxml()>, let me know.
=head1 DEVELOPMENT
If you are a developer wanting to extend B<Business::PayPal::API> for
other PayPal API calls, you can review any of the included modules
(e.g., F<RefundTransaction.pm> or F<ExpressCheckout.pm>) for examples
on how to do this until I have more time to write a more complete
document.
But in a nutshell:
package Business::PayPal::API::SomeAPI;
use 5.008001;
use strict;
use warnings;
use SOAP::Lite 0.67;
use Business::PayPal::API ();
our @ISA = qw(Business::PayPal::API);
our @EXPORT_OK = qw( SomeAPIMethod );
sub SomeAPIMethod {
...
}
Notice the B<@EXPORT_OK> variable. This is I<not> used by B<Exporter>
(we don't load Exporter at all): it is a special variable used by
B<Business::PayPal::API> to know which methods to import when
B<Business::PayPal::API> is run like this:
use Business::PayPal::API qw( SomeAPI );
That is, B<Business::PayPal::API> will import any subroutine into its
own namespace from the B<@EXPORT_OK> array. Now it can be used like this:
use Business::PayPal::API qw( SomeAPI );
my $pp = Business::PayPal::API->new( ... );
$pp->SomeAPIMethod( ... );
Of course, we also do a 'use Business::PayPal::API' in the module so
that it can be used as a standalone module, if necessary:
use Business::PayPal::API::SomeAPI;
my $pp = Business::PayPal::API::SomeAPI->new( ... ); ## same args as superclass
$pp->SomeAPIMethod( ... );
Adding the B<@EXPORT_OK> array in your module allows your module to be
used in the most convenient way for the given circumstances.
=head1 EXAMPLES
Andy Spiegl <paypalcheckout.Spiegl@kascada.com> has kindly donated
some example code (in German) for the ExpressCheckout API which may be
found in the F<eg> directory of this archive. Additional code examples
for other APIs may be found in the F<t> test directory.
=head1 EXPORT
None by default.
=head1 CAVEATS
Because I haven't figured out how to make SOAP::Lite read the WSDL
definitions directly and simply implement those (help, anyone?), I
have essentially recreated all of those WSDL structures internally in
this module.
(Note - 6 Oct 2006: SOAP::Lite's WSDL support is moving ahead, but
slowly. The methods used by this API are considered "best practice"
and are safe to use).
As with all web services, if PayPal stop supporting their API
endpoint, this module *may stop working*. You can help me keep this
module up-to-date if you notice such an event occurring.
Also, I didn't implement a big fat class hierarchy to make this module
"academically" correct. You'll notice that I fudged colliding
parameter names in B<DoExpressCheckoutPayment> and similar fudging may
be found in B<GetTransactionDetails>. The good news is that this was
written quickly, works, and is dead-simple to use. The bad news is
that this sort of collision might occur again as more and more data is
sent in the API (call it 'eBay API bloat'). I'm willing to take the
risk this will be rare (PayPal--please make it rare!).
=head1 ACKNOWLEDGEMENTS
Wherein I acknowledge all the good folks who have contributed to this
module in some way:
=over 4
=item * Daniel P. Hembree
for authoring the AuthorizationRequest, CaptureRequest,
DirectPayments, ReauthorizationRequest, and VoidRequest extensions.
=item * <jshiles at base16consulting daught com>
for finding some API typos in the ExpressCheckout API
=item * Andy Spiegl <paypalcheckout.Spiegl@kascada.com>
for giving me the heads-up on PayPal's new 3-token auth URI and for a
sample command-line program (found in the 'eg' directory)
demonstrating the ExpressCheckout API.
=item * Ollie Ready <oready at drjays daught com>
for the heads-up on the newest 3-token auth URI as well as a pile of
documentation inconsistencies.
=item * Michael Hendricks <michael at ndrix daught org>
for a patch that adds ShippingTotal to the DirectPayments module.
=item * Erik Aronesty, Drew Simpson via rt.cpan.org (#28596)
for a patch to fix getFields() when multiple items are returned
=item * Sebastian Böhm via email, SDC via rt.cpan.org (#38915)
for a heads-up that the PayPal documentation for MassPay API was wrong
regarding the I<UniqueId> parameter.
=item * Jonathon Wright via email
for patches for B<ExpressCheckout> and B<RecurringPayments> that
implement I<BillingAgreement> and I<DoReferenceTransaction> API
calls.
=back
=head1 SEE ALSO
L<SOAP::Lite>,
L<PayPal User Guide|https://developer.paypal.com/webapps/developer/docs/classic/products>,
L<PayPal API Reference|https://developer.paypal.com/webapps/developer/docs/api/overview>
=head1 AUTHORS
=over 4
=item *
Scott Wiersdorf <scott@perlcode.org>
=item *
Danny Hembree <danny@dynamical.org>
=item *
Bradley M. Kuhn <bkuhn@ebb.org>
=back
=head1 COPYRIGHT AND LICENSE
This software is copyright (c) 2006-2017 by Scott Wiersdorf, Danny Hembree, Bradley M. Kuhn.
This is free software; you can redistribute it and/or modify it under
the same terms as the Perl 5 programming language system itself.
=cut