Re: Issue 6917: preliminary proposal for Event Tags; filtering

In this particular case I would expect a new FormatURI to be defined (and 
used in the Subscribe) - one that said "put the eventTag element(s) as 
soap headers" since the default formatURI (raw) doesn't tell us this.  It 
important to note that any extra data associated with an event (and there 
could be a lot of it) may, or may not, manifest itself on the wire - this 
is a choice the Subscriber can make through the choice of formatURI.

thanks
-Doug
______________________________________________________
STSM |  Standards Architect  |  IBM Software Group
(919) 254-6905  |  IBM 444-6905  |  dug@us.ibm.com
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Gilbert Pilz <gilbert.pilz@oracle.com> 
Sent by: public-ws-resource-access-request@w3.org
07/31/2009 04:45 PM

To
"public-ws-resource-access@w3.org" <public-ws-resource-access@w3.org>
cc

Subject
Issue 6917: preliminary proposal for Event Tags; filtering






Once we have a way of describing our tags and linking them to the Event 
Types to which they apply (see [1]), it is straightforward to define an 
"Event Tag Filter" that operates over the values of 
/wse:EventDescriptions/wse:eventType/wse:eventTag.

<wse:Subscribe>
  <wse:Delivery>
    <wse:NotifyTo>
      <wsa:Address>http://www.other.example.com/OnStormWarning
</wsa:Address>
      <wsa:ReferenceParameters>
        <ew:MySubscription>2597</ew:MySubscription>
      </wsa:ReferenceParameters>
    </wse:NotifyTo>
  </wse:Delivery>
  <wse:Filter Dialect="http://www.w3.org/2009/02/ws-evt/tagFilter">
    <wse:eventTag>wind</wse:eventTag>
  </wse:Filter>
</wse:Subscribe>

The above request would select the events tagged with "wind" from the set 
of the Event Types supported/produced by the Event Source. We might want 
to allow the tagFilter dialect to include multiple wse:eventTag elements 
to support the selection of multiple tags in a single subscription, but 
things get a bit complicated if we want to distinguish between selecting 
events with "this tag or that tag" and "this tag and that tag" (there are 
use cases for both).

As stated previously (and requested by Ben in the original comment) the 
tags associated with an Event appear as SOAP headers in the Notification.

<s12:Envelope xmlns:s12="http://www.w3.org/2003/05/soap-envelope"
              xmlns:wsa="http://www.w3.org/2005/08/addressing"
              xmlns:ew="http://www.example.com/warnings"
              xmlns:ow="http://www.example.org/oceanwatch" >
  <s12:Header>
    <wsa:Action>http://www.example.org/oceanwatch/2003/WindReport
</wsa:Action>
     
<wsa:MessageID>uuid:568b4ff2-5bc1-4512-957c-0fa545fd8d7f</wsa:MessageID>
     <wsa:To>http://www.other.example.com/OnStormWarning</wsa:To>
     <ew:MySubscription 
wsa:IsReferenceParameter="true">2597</ew:MySubscription>
     <wse:eventTag>weather</wse:eventTag>
     <wse:eventTag>wind</wse:eventTag>
  </s12:Header>
  <s12:Body>
    <ow:WindReport>
      <ow:Date>030701</ow:Date>
      <ow:Time>0041</ow:Time>
      <ow:Speed>65</ow:Speed>
      <ow:Location>BRADENTON BEACH</ow:Location>
      <ow:County>MANATEE</ow:County>
      <ow:State>FL</ow:State>
      <ow:Lat>2746</ow:Lat>
      <ow:Long>8270</ow:Long>
      <ow:Comments xml:lang="en-US" >
        WINDS 55 WITH GUSTS TO 65. ROOF TORN OFF BOAT HOUSE. REPORTED
        BY STORM SPOTTER. (TBW)
      </ow:Comments>
    </ow:WindReport>
  </s12:Body>
</s12:Envelope>

Among other things, this supports the use of multiple tags in a single 
subscription by providing the Event Sink with the tag information at 
Notification time.

[1] 
http://lists.w3.org/Archives/Public/public-ws-resource-access/2009Jul/0093.html


- gp