Web Services: TopDown vs. BottomUp

As I am going through some more web-services related work, I came across two arguments to favor TodDown (or WSDL first) design pattern:

1) Including the partner link information that BPEL is expecting to find is trivial when you own the WSDL document. Try to get this added at the end of your document, using code first...

<plnk:partnerLinkType name="StepTransform"
xmlns:plnk="http://schemas.xmlsoap.org/ws/2003/05/partner-link/">
<plnk:role name="XmlStepTransformPort">
<plnk:portType name="tns:XmlStepTransformPort"/>
</plnk:role>
</plnk:partnerLinkType>

2)Adding wsdl:documentation element within wsdl:portType/wsdl:operation will improve the end-user experience, and should be done always. It's like arguing against the value of javadoc on external APIs....

Today, the mood is WSDL first: Design, then code.

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