Hello,

I have stumbled across a problem when trying to filter a NotificationMessage
with an XPath expression containing namespace declarations (e.G.
//om:Observation/om:procedure - where om is "http://www.opengis.net/om/1.0
").
Perhaps I made some mistake while subscribing with this filter, but to me it
seems, that the MessagePatternFilter just invokes XPathUtils.isMatch().
isMatch itself invokes XPathAPI.eval(context, xpath) [from apache xalan api]
and that method has no parameter for the namespaceNode. This has the result
that the XPath expression takes its namespaces from the NotificationMessage,
which of course may differ from the ones specified in my subscribe request.

Also I noticed that namespaces in a MessagePatternFilter xml file (see
below) just get erased when parsing the xml with the FilterFactory.

Filter to parse:
<wsnt:Filter xmlns:wsnt="http://docs.oasis-open.org/wsn/b-2";>
    <wsnt:MessageContent Dialect="
http://www.w3.org/TR/1999/REC-xpath-19991116";
        xmlns:om="http://www.opengis.net/om/1.0";>

//om:Observation/om:procedure/@xlink:href='urn:ogc:object:procedure:CITE:WeatherService:LGA'
    </wsnt:MessageContent>
</wsnt:Filter>


this gets parsed in the subscribe operation of NotificationProducer (I
assume this is done before in the FilterFactory):
<wsnt:Filter xmlns:wsnt="http://docs.oasis-open.org/wsn/b-2";>
<wsnt:MessageContent Dialect="http://www.w3.org/TR/1999/REC-xpath-19991116
">//om:Observation/om:procedure/@xlink:href='urn:ogc:object:procedure:CITE:WeatherService:LGA'</wsnt:MessageContent>
</wsnt:Filter>


As you can see the namespace "om:...." is removed.

Did i make a mistake or is there any kind of solution for this problem?

Regards,
Matthes

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