[MOBY-l] MobyRequest problem

[Paul Gordon]

Hey folks,

    Now that we have different clients, and different servers running, 
we see the ugly face of interoperability :-P
The major issue here is that the Java client is not finding the SOAP 
base64 encoded payload because the XPath expression used to find it in 
the SOAP envelope is

//*[@xsi:type="SOAP-ENC:base64"]

This has two issues, one is easy to fix, the other not so.  XML Schema 
Instances are wierd because they use prefixes like SOAP-ENC to describe 
the namespace of tags.  But that prefix is not part of the syntax of the 
XML document, it's just CDATA in an attribute.  But the prefix 
declaration is done in the document (xmlns:SOAP-ENC="http://....").  
There is no systematic way to apply the declared prefix to the 
xsi:type="SOAP-ENC:base64" bit, since it's just CDATA.  Anyhow, we can 
avoid this whole match-the-variable-prefix-to-a-XSI-meta-data-namespace 
problem by changing the XPath to be more inclusive. Just looking at the 
local name (i.e. unprefixed) part of the CDATA after the colon

//*[substring-after(@xsi:type, ':')=\"base64\"]"

at the very slight risk that you have other top-level SOAP envelope XSI 
declarations of "base64" that aren't SOAP (i.e. you're doing some very 
wierd handtweaking of the SOAP envelope with element name collision).

The second problem is that Perl service providers use as module that 
uses the XML Schema Instance namespace of 
http://www.w3.org/1999/XMLSchema-instance, whereas Apache's Java Axis 
uses http://www.w3.org/2001/XMLSchema-instance.  So should the XPath 
bind xsi: to the the former or the latter?  For now I had hardcoded in 
the 1999 version, since most service providers were using the Perl 
modules.  See the MobyPrefixResover code and its accompanying comment

else if(XSI_PREFIX.equals(prefix)){
    return XSI_NAMESPACE1999;  //Crappy Perl XML Schema namespace usage 
is out of date
}

You see, I precompile the XPath statements for speed, so I need to know 
beforehand if 1999 or 2001 namespace will be used.  Ben, can you make 
your Echo service available with a real IP address? That way I can try 
to fix this with multiple XSI resolutions and test it before commiting.