SOAPAction header

asap message

Those who have gotten the demo running know that the .Net client requires there be a SOAPAction header to the HTTP request. Last week Jeff changed the .Net client/server so that it does not use this in its decision on what to do with the message. Instead it uses the first tag inside the body tag, same as the ASAP specification required.

Upon further testing, the SOAPAction header is still required. It is not required to have any value, and can be empty, but the .Net framework will complain if the header is completely missing. The SOAP 1.1 spec says that the SOAPAction header is required. To ensure interoperability, all SOAP HTTP requests must have a SOAPAction HTTP header.

The specification is vague on what this is used for. I am completely against any such construct. The complete information of the exchange should be held in the SOAP message itself, for the rather obvious reason that if the message takes several hops to be transferred, (e.g. it is sent by email and then by HTTP) information carried outside the message itself will not be reliably carried forward. The SOAPAction header is supposed to be an additional indication of the 'intent' of the message, but if the message itself does not completely specify its intent, then the correct way to solve it is to add this additional information to the message itself, and not into transport layer field which can not be described by XML Schema!

For this reason I would like to propose that all ASAP implementations, when using HTTP, MUST include a SOAPAction header, and that header MUST be an empty string value.

(And for those implementer worried about last minute changes: this does not represent a change to the spec or to any of the implementation. Anyone who got the demo running already has the SOAPAction header in place. This is simply clarifying the precise interpretation of the SOAP spec, and proposing a future (post demo) clarification to add to the spec and protocol.)

Keith D Swenson, kswenson@us.fujitsu.com
Fujitsu Software Corporation
1250 E. Arques Avenue, Sunnyvale, CA 94085
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