Re: web services & _parseFault (still lost)

FROM : Zach Wily
DATE : Wed Jun 30 22:28:22 2004

>> Not sure how you're getting 3 versions. I think that you specify when 
>> you create
>> the stubs if you want Obj-C, C++, or AppleScript.

>
> Using the XMethodsInspector example app, selecting the desired service 
> and click fetch.  I use the Obj-C stubs, and I seem to always get 3 
> (duplicate?) implementations of each class.  For example in the case 
> of this WDSL ( see URL below ), I get stubs for classes GetLicRate & 
> GetRate ( 3 implementations for each ) and 1 implementation for the 
> synchronous class CurrencywsService which has all class method 
> implementations--calling the others.  Maybe there are versions for 
> SOAP and straight XML, but I figured the service would respond to 
> either one or the other, not both??


It looks like the WSDL is declaring some variants of the methods that 
distinguish between SOAP/HTTP GET/HTTP POST requests, and the stubs 
generator (probably WSMakeStubs) isn't handling them correctly.

>> Let me know what service you're connecting to (WSDL would be nice) 
>> and I'll see
>> if I can help.

>
> http://glkev.webs.innerhost.com/glkev_ws/Currencyws.asmx?WSDL
>
> Also, when it is unclear what the parameter should be or look like, is 
> there a way to find out?  Again, inspecting the service's profile 
> online or embedded comments within the stubs often does not yield any 
> clues.


I went ahead and generated some stubs myself from that WSDL and built a 
small project. After I deleted the extra implementations of those two 
methods, I ran it, and with ethereal sniffed the server response. I 
don't have it to paste in, but it said something about the SOAPAction 
header missing. Then I remembered that WSMakeStubs seems to have a bug 
where it doesn't set those, but .NET likes (demands) them. The 
SOAPAction that the .NET service is expecting looks like 
base_url/method_name. So for example, I made -[GetRate 
genCreateInvocationRef] look like this:

- (WSMethodInvocationRef) genCreateInvocationRef
{
    return [self createInvocationRef
                /*endpoint*/: 
@"http://glkev.webs.innerhost.com/glkev_ws/Currencyws.asmx"
                  methodName: @"GetRate"
                  protocol: (NSString*) kWSSOAP2001Protocol
            // missing encoding style - defaulting to RPC
                      style: (NSString*) kWSSOAPStyleRPC
                  soapAction: @"http://www.myasptools.com/GetRate" /* No 
SOAPAction header needed (zwily: oh yes it is!!) */
            methodNamespace: NULL /* No Method Namespace specified */
        ];
}

So that sends in the right SOAPAction, but then there's ANOTHER bug 
where WSGeneratedObj that doesn't actually set that correctly. So in 
WSGeneratedObj.m on lines 174 and 175:

                        NSString* soapAction = @"SOAPAction";
                        NSDictionary* headers = [self 
copyHeaderDictionary:1 extraVals:&soapAction extraKeys:&soapAction];

Change these to:

                        NSString* soapActionKey = @"SOAPAction"; // the 
name soapAction is taken by the method parameter
                        NSDictionary* headers = [self 
copyHeaderDictionary:1 extraVals:&soapAction extraKeys:&soapActionKey];

After making all these changes, here's what the web service is 
responding with (once again, caught with ethereal):

<?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="">
  <soap:Body>
    <soap:Fault>
      <faultcode>soap:Server</faultcode>
      <faultstring>System.Web.Services.Protocols.SoapException: Server 
was unable to process request. ---&gt; System.NullReferenceException: 
Object reference not set to an instance of an object.
    at LicenseChecker.CheckSecurity()
    at Currencyws.GetRate(String srcCurrency, String destCurrency)
    --- End of inner exception stack trace ---</faultstring>
      <detail />
    </soap:Fault>
  </soap:Body>
</soap:Envelope>

The "LicenseChecker.CheckSecurity()" line leads me to believe that it's 
expecting some sort of authentication token to be passed in, but I 
could be wrong.

Anyway, I gave up on the generated stubs awhile ago and just work 
straight with the Web Services API's documented here:

http://developer.apple.com/documentation/Networking/Conceptual/
UsingWebservices/3_ref_folder/chapter_3_section_1.html#//apple_ref/doc/
uid/TP30000985-CH206-BBCFFFHC

I hope this helps...

zach
_______________________________________________
MacOSX-dev mailing list
<email_removed>
http://www.omnigroup.com/mailman/listinfo/macosx-dev