PB & web service : how to manipulate soap envelop ?

Question

Hi all,
I am in the process of testing PB's ability to consume an existing web service. I have done some reading left and right.
I can create the proxy , but i always end up having the Cannot invoke webservice messagebox.
Here's my little piece of PB code 
PB CODE START
soapconnection conn // Define SoapConnection
checkvatport proxy_obj // Declare proxy
long rVal, lLog
real amount
date date_a
string ls_a,ls_b,ls_c
conn = create soapconnection  //Instantiated connection
lLog = conn.SetSoapLogFile ("C:\mySoapLog.log")
rVal = Conn.CreateInstance(proxy_obj, "checkvatport", "")
messagebox("test rval",string(rval))
// Create proxy object
try
   date_a = today()
  boolean w_t
  w_t = TRUE
   str_checkvat str1
   tns1__checkvatresponse str2
  str1.countrycode = "BE"
  str1.vatnumber = "0810416786"
  ls_a  = proxy_obj.checkvat(str1.countryCode,str1.vatNumber,str2.requestdate,str2.valid,str2.address)
  messagebox("LS-a",ls_a)
catch ( SoapException e )
   messagebox ("Error", "Cannot invoke Web service")
   // error handling  
end try
destroy conn
PB CODE END
And here's the soaplog contents
SOAPLOG START
CLOSED
REQUEST:
CLOSED
POST /taxation_customs/vies/services/checkVatService HTTP/1.1
Host: ec.europa.eu
Connection: Keep-Alive
User-Agent: EasySoap++/0.6
Content-Type: text/xml; charset=utf-8
SOAPAction: "urn:ec.europa.eu:taxud:vies:services:checkVat#checkVat"
Content-Length: 654
<E:Envelope
  xmlns:E="http://schemas.xmlsoap.org/soap/envelope/"
  xmlns:A="http://schemas.xmlsoap.org/soap/encoding/"
  xmlns:s="http://www.w3.org/2001/XMLSchema-instance"
  xmlns:y="http://www.w3.org/2001/XMLSchema"
  E:encodingStyle="http://schemas.xmlsoap.org/soap/encoding/">
<E:Body>
<m:checkVat
  xmlns:m="urn:ec.europa.eu:taxud:vies:services:checkVat:types">
<ns1:countryCode
  xmlns:ns1="urn:ec.europa.eu:taxud:vies:services:checkVat"
  s:type="y:string">BE</ns1:countryCode>
<ns2:vatNumber
  xmlns:ns2="urn:ec.europa.eu:taxud:vies:services:checkVat"
  s:type="y:string">0810416786</ns2:vatNumber>
</m:checkVat>
</E:Body>
</E:Envelope>
RESPONSE:
HTTP/1.1 500 Internal Server Error
Date: Wed, 04 Jun 2014 09:33:11 GMT
Transfer-Encoding: chunked
Content-Type: text/xml; charset=UTF-8
Server: Europa
Connection: Keep-Alive
Transfer is Chunked!
01d7
<soap:Envelope xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/"><soap:Body><soap:Fault><faultcode>soap:Client</faultcode><faultstring>Unmarshalling Error: unexpected element (uri:"urn:ec.europa.eu:taxud:vies:services:checkVat", local:"countryCode"). Expected elements are &lt;{urn:ec.europa.eu:taxud:vies:services:checkVat:types}vatNumber>,&lt;{urn:ec.europa.eu:taxud:vies:services:checkVat:types}countryCode> </faultstring></soap:Fault></soap:Body></soap:Envelope>
0000
GetChunkLength: 01d7 = 471
Connection Disconnected
SOAPLOG END
Now i tried the to cut and paste the above soap envelop in SOAPUI , and it gives me the exact same error message as in the soaplog.
I then tried creating a request through SOAPUI but based on the wdsl ,SOAPUI is giving me a different soap envelop as the one PB generated ?
<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/" xmlns:urn="urn:ec.europa.eu:taxud:vies:services:checkVat:types">
   <soapenv:Header/>
   <soapenv:Body>
      <urn:checkVat>
         <urn:countryCode>?</urn:countryCode>
         <urn:vatNumber>?</urn:vatNumber>
      </urn:checkVat>
   </soapenv:Body>
</soapenv:Envelope>
If i enter parameters in the above envelop and check it through SOAPUI , i end up having the result i want.
Is there any way we can manipulate the soap envelop contents ? Or does anyone have any idea why the soap envelop generated by PB ends up having the above mentioned error in the soaplog file ?
What am i missing ?
TIA
John

Answer 1

You're using the EasySOAP proxy.  You didn't mention what version of PowerBuilder, but if you're using a version that supports the .Net engine instead use that.  The EasySOAP web service support is quite old.
Once you do that you won't be able to use the log.  Instead, use something like Fiddler to trap the request and response.