SOAP::Lite remote objects

[tjking]

Hi Monks,

I'm trying to create a webservices wrapper for a module whose structure doesn't seem to be compatible with direct dispatching. I need to build up a bunch of state before executing the module calls from the server, but there seems to be concurrency issues with the approach I'm taking, and wonder if anyone can spot my mistake in the following stub.

Server:

#!perl -w
use SOAP::Transport::HTTP;
SOAP::Transport::HTTP::Daemon
->new(LocalPort=>1111,ReuseAddr=>1)
-> dispatch_to('TestWrapper') 
-> handle;

package TestWrapper;
use Data::Dumper;

sub new {
        my $self = shift;
        my $class = ref($self) || $self;
        return bless {} => $class;
}

sub put {
        my ($self, $key, $val) = @_;
        $self->{_HASH}{$key} = $val;
}

sub get {
        my ($self, $key) = @_;
        return $self->{_HASH}{$key};
}

1;

Client:

use strict;
use warnings;
use SOAP::Lite;

my $soap = SOAP::Lite
-> uri('http://localhost:1111/TestWrapper')
-> proxy('http://localhost:1111/');

my $t1 = $soap->new();
$t1->put('element1', 'value1');

my $t2 = $soap->new();
$t2->put('element1', 'value2')->result;

printf("t1 : %s\n", $t1->get('element1')->result);
printf("t2 : %s\n", $t2->get('element1')->result);

I'm currently getting the following output from the client:

$ perl client.pl 
t1 : value2
t2 : value2

Both references seem to end up pointing at the same object, causing the hash entry to get overwritten, and this even happens if I create the objects in two separate scripts and run them concurrently. However, if I create the objects directly (i.e. not via SOAP), everything works as expected:

use TestWrapper;

my $t1 = new TestWrapper;
$t1->put('element1', 'value1');

my $t2 = new TestWrapper;
$t2->put('element1', 'value2');

printf("t1 : %s\n", $t1->get('element1'));
printf("t2 : %s\n", $t2->get('element1'));

output:

$ perl standalone.pl 
t1 : value1
t2 : value2

Any input would be most appreciated. I'm using ActivePerl 5.14 and SOAP::Lite 0.714.

[McA]

Hi,


I can't run the code on my side. So what I'm saying is a guess looking at your code and at the documentation.

Are you sure that the code snippet my $t1 = $soap->new(); does a remote call to 'new' to instantiate an object on the remote site? I guess not. I assume that 'new' is called on SOAP::Lite.

Is my $t1 = $soap->call('new'); the solution?

Probaby you make a cross check calling your object creation method in TestWrapper not 'new' but e.g. 'mynew'.

Best regards
McA

[tjking]

Yes, it's instantiating a TestWrapper object, or it wouldn't be giving the client output that I'm already getting. Renaming the constructor results in "Can't locate object method "put" via package "SOAP::SOM" at client.pl line 10.". Using $soap->call('new') instead of $soap->new() makes no difference either way.

The problem is, the SOAP::Lite documentation and examples that are out there are severely out of date, and many do not work at all with the current version. The only example I could find for remote instantiation was this one, which does work. However, only the constructor takes a user-defined argument, the subsequent method call is static, and only takes the object returned by call(). Unfortunately, I can't seem to figure out how to get this to work with regular methods that take additional arguments (other than the object itself).

Thanks for the input!