Walking the SOAP/WSDL fault line

Walking the fault lines

I've been plugging away with a handful of toolkits -- .NET, SOAP::Lite, GLUE, and Radio -- trying to get a feel for where the SOAP/WSDL fault lines actually are. Today, Jake Savin articulates what I've begun to suspect also: there are a lot of ways to encode things in SOAP, and this complicates the problem of typing them in WSDL.

I don't see this as simply a static/dynamic language issue. Whether or not a toolkit can or will autogenerate WSDL for some service, you should (as Simon Fell did) be able to figure out how to write the WSDL, should you choose to provide it. And when you can successfully do so, you make your service frictionlesslessly available to a lot of people.

So far, I'm finding simple things (like arrays of strings) to be possible, and hard things (like hashes of lists, and lists of hashes) to be very difficult.

Kind of makes me wish for the good old days:

Here's an example of a two-element <struct>:

<struct>
   <member>
      <name>lowerBound</name>
     
<value><i4>18</i4></value>
      </member>
   <member>
      <name>upperBound</name>
     
<value><i4>139</i4></value>
      </member>
   </struct>

<struct>s can be recursive, any <value> may contain a <struct> or any other type, including an <array>.

What, exactly, was missing from this tiny nugget of gold?


Former URL: http://weblog.infoworld.com/udell/2002/02/19.html#a72