WS Description and "safety"

Dear TAG,

Almost a year ago, the TAG expressed some pleasure [1] at the WS
Description WG's native support for operation safety.  As we have
recently made some changes in this area, we thought it might be useful
to provide an update to the TAG.

Up through our recent public Working Drafts, we document a {safety}
property and an associated attribute @safe as a property of the WSDL
Core component model [2, esp. 6th bullet].  However, we received an
issue [3] about the inability for tools to infer useful values for this
attribute and the consequent impact on wide adoption.  This discussion
exposed significant differences remaining in the Working Group around
operation safety.  We had objectors to removing the property altogether,
yet also had significant objection to retaining the status quo.

We settled on a compromise in two parts:

1) The "safe" attribute would be moved to an extension namespace and
documented in the Adjuncts spec instead of the Core spec.  This
satisfied those who felt that a semantic extension was inappropriate in
the Core (which otherwise concerns itself with the mechanics of
communication, not the semantics.)

2) The HTTP binding would take a dependency upon the safe attribute, and
when the safe property is set to true, the HTTP method would default to
GET, though this can be overridden when other considerations (e.g. data
not easily serialized in a URI) apply.  This satisfied those who felt
safety was important enough to not only remain in the family of
Recommendations, but to have a real effect on the HTTP binding.

I took an action as chair to update you on the current situation.  I'd
be happy to answer questions or provide you more detail if you wish.

- Jonathan Marsh
  WS Description WG


Received on Tuesday, 7 June 2005 22:11:15 UTC