Having trouble accessing object's instance variable in Perl SOAP server code - perl

Question

I'm working through example SOAP client/server code using SOAP::Transport::HTTP:Daemon and SOAP::Lite, and I've noticed that I cannot access an instance variable declared in an object's new() method. I'm sure I'm doing something wrong, but I'm not sure what (although it has been years since I was a half-decent Perl programmer).
Here's my server:
#! /usr/bin/env perl
use lib '/a/valid/directory/modules';
use SOAP::Transport::HTTP;
my $port = 9810;
my $dispatchers = {
'urn:remote_call' => 'ExampleLibrary::MyExample'
};
my $daemon = SOAP::Transport::HTTP::Daemon
-> new (LocalAddr => 'localhost', LocalPort => $port)
-> dispatch_with($dispatchers)
-> on_action(sub {return})
;
print "Connect to SOAP server at ", $daemon->url, "\n";
$daemon->handle;
Here's my client (located in a directory specified in the server's use lib line, modules/ExampleLibrary/MyExample.pm):
package ExampleLibrary::MyExample;
use vars qw(#ISA);
#ISA = qw(Exporter SOAP::Server::Parameters);
use SOAP::Lite;
sub new {
my($class, %args) = #_;
my $self = bless({}, $class);
$self->{somevar} = 'somedata';
return $self;
}
sub remote_call {
my $self = shift;
my $envelope = pop;
# Swap out return statements and the data is returned correctly
# return SOAP::Data->type('xml' => 'foo');
return SOAP::Data->type('xml' => "$self->{somevar}");
}
1;
I'm sure I'm hitting the client correctly--I can put in static text in the remote_call's return statement (the commented out code) and see it--but the object data specified as $self->{somevar} is never visible, with or without quotes. (I'm using SoapUI to hit the server.)
Does anyone see what I'm missing? (Oh, I'm using Perl v5.10.1 on Cygwin.)
Thanks...

Answer 1

The docs say
dispatch_with({
URI => MODULE, # 'http://www.soaplite.com/' => 'My::Class',
SOAPAction => MODULE, # 'http://www.soaplite.com/method' => 'Another::Class',
URI => object, # 'http://www.soaplite.com/obj' => My::Class->new,
})
You have
my $dispatchers = {
'urn:remote_call' => 'ExampleLibrary::MyExample'
};
maybe that should be
my $dispatchers = {
'urn:remote_call' => 'ExampleLibrary::MyExample->new'
};
Otherwise (I speculate that) your method may be being invoked as a static method not as an instance method (no instance having been instantiated).
P.S. The absence of single-quotes for the object instantiation string in the docs puzzles me as it suggests that a single instance is used to handle all requests (and that seems wrong to me) but maybe that is indeed what this experimental feature needs and you should omit the single quotes too.

Answer 2

I got this working after tweaking the code a bit from #RedGrittyBrick's suggestion (or perhaps it's exactly what he suggested and I just didn't understand it). Thanks also to #Axeman--you came back multiple times to try and help out--I appreciate that very much. I put comments in the server to indicate the two lines that fixed things.
Here's the revised server:
#! /usr/bin/env perl
use lib '/a/valid/directory/modules';
use ExampleLibrary::MyExample; # new!
use SOAP::Transport::HTTP;
my $port = 9810;
my $dispatchers = {
# new--no quotes around the hash value
'urn:remote_call' => ExampleLibrary::MyExample->new
};
my $daemon = SOAP::Transport::HTTP::Daemon
-> new (LocalAddr => 'localhost', LocalPort => $port)
-> dispatch_with($dispatchers)
-> on_action(sub {return})
;
print "Connect to SOAP server at ", $daemon->url, "\n";
$daemon->handle;
Here's the revised client. Really, the only changes were to put localtime() calls in so that I could verify that variables set in new() remained unchanged over the lifetime of the server.
package ExampleLibrary::MyExample;
use vars qw(#ISA);
#ISA = qw(Exporter SOAP::Server::Parameters);
use SOAP::Lite;
sub new {
my($class, %args) = #_;
my $self = bless({}, $class);
$self->{'somevar'} = localtime();
return $self;
}
sub remote_call {
my $self = shift;
my $envelope = pop;
$now = localtime();
return SOAP::Data->type('xml' => "now = $now, started at $self->{somevar}");
}
1;