GetSpeech Worked - Using SOAP::Data Class and on

SOAP Web Service Tutorials - Herong's Tutorial Examples

∟Perl SOAP::Lite for GetSpeech SOAP 1.1 Web Service

∟GetSpeech Worked - Using SOAP::Data Class and on_action() Function

This section provides a tutorial example on how to use the SOAP::Data class to build the request parameter element with correct element name and a namespace. My first SOAP::Lite program works now with the GetSpeech Web service.

In the previous tutorial, I confirmed that the parameter name "c-gensym3" generated with SOAP::Lite default setting is the root cause of the exception of "System.Web.Services.Protocols.SoapException: Server was unable to process request. ---> System.NullReferenceException: Object reference not set to an instance of an object."

What SOAP::Lite function should I use to fix this issue? Looking at the ActivePerl SOAP::Lite manual again, I found this class:

SOAP::Data
   You can use this class if you want to specify a value, a name, 
   atype, a uri or attributes for SOAP elements (use value(), name(), 
   type(), uri() and attr() methods correspondingly). For example, 
   SOAP::Data->name('abc')->value(123) will be serialized into 
   <abc>123</abc>, as well as will SOAP::Data->name(abc => 123). Each 
   of them (except the value() method) can accept a value as the 
   second parameter. All methods return the current value if you call 
   them without parameters. The return the object otherwise, so you 
   can stack them.

Based on the above description I revised my test program as GetSpeech_Parameter_Name.pl:

#- GetSpeech_Parameter_Name.pl
#- Copyright (c) 2009 HerongYang.com. All Rights Reserved.
#- All rights reserved
#
   use SOAP::Lite +trace;
   my $client = SOAP::Lite->new();
   $client->proxy('http://www.xmlme.com/WSShakespeare.asmx');

#- Fixing the SOAPAction header line - join uri and method name with /
   $client->uri('http://xmlme.com/WebServices');
   $client->on_action(sub { join '/', @_ });

#- Building the parameter element with name and namespace
   my $parameter = SOAP::Data
        ->uri('http://xmlme.com/WebServices')
        ->name(Request)
        ->value("To be, or not to be");

#- Calling the server
   my $som = $client->GetSpeech($parameter);
   my $output = $som->result;
   print $output . "\n";

Here is what I did in this program:

The string parameter is replaced with a SOAP::Date object, $parameter, when calling the Web service method GetSpeech().
A URI string is added with uri() as the namespace for $parameter.
"Request" is added with name() as the name for $parameter.
"To be, or not to be" is added with value() as the value for $parameter.
When calling GetSpeech($parameter), $parameter will be serialized as the parameter element.

When executing GetSpeech_Parameter_Name.pl, I got this:

herong> GetSpeech_Parameter_Name.pl
...
POST http://www.xmlme.com/WSShakespeare.asmx
Accept: text/xml
Accept: multipart/*
Content-Length: 597
Content-Type: text/xml; charset=utf-8
SOAPAction: http://xmlme.com/WebServices/GetSpeech

<?xml version="1.0" encoding="UTF-8"?>
<SOAP-ENV:Envelope
  xmlns:xsi="http://www.w3.org/1999/XMLSchema-instance"
  xmlns:SOAP-ENC="http://schemas.xmlsoap.org/soap/encoding/"
  xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/"
  xmlns:xsd="http://www.w3.org/1999/XMLSchema"
  SOAP-ENV:encodingStyle="http://schemas.xmlsoap.org/soap/encoding/">
  <SOAP-ENV:Body>
    <namesp1:GetSpeech xmlns:namesp1="http://xmlme.com/WebServices">
      <namesp2:Request xsi:type="xsd:string"
        xmlns:namesp2="http://xmlme.com/WebServices">
        To be, or not to be
      </namesp2:Request>
    </namesp1:GetSpeech>
  </SOAP-ENV:Body>
</SOAP-ENV:Envelope>
...
HTTP/1.1 200 OK
Cache-Control: private, max-age=0
Connection: close
Date: ... 2009
Server: Microsoft-IIS/6.0
Content-Length: 1942
Content-Type: text/xml; charset=utf-8
Client-Date: ... 2009
Client-Peer: ...
Client-Response-Num: 1
X-AspNet-Version: 2.0.50727
X-Powered-By: ASP.NET

<?xml version="1.0" encoding="utf-8"?>
<soap:Envelope xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xmlns:xsd="http://www.w3.org/2001/XMLSchema">
  <soap:Body>
    <GetSpeechResponse xmlns="http://xmlme.com/WebServices">
      <GetSpeechResult><SPEECH><PLAY>HAMLET</PLAY>
        <SPEAKER>HAMLET</SPEAKER>To be, or not to be: 
        that is the question: Whether 'tis nobler in the mind
        ...</SPEECH>
      </GetSpeechResult>
    </GetSpeechResponse>
  </soap:Body>
</soap:Envelope>
...