[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [xmlblaster] Querying Qos with XPath ?

Cyrille Giquello wrote: 
again on da line,

I try, but can't querying the Qos with XPath ...
Perhaps it's my Query, or querying Qos is not supported ???

XPath Query = /xmlBlaster/qos/sender['test']

Qos of message =
<qos>
   <state> OK </state>
   <sender> test </sender>
   <rcvTimestamp millis=\'1013695176202\'>2002-02-14 14:59:36.202</rcvTimestamp>
   <expiration timeToLive=\'129599762\'/>
</qos>


Query of QoS with XPath is not possible.
I even never thought of such a use case.

Hmm, is this a feature we should have?

I see some performance problems with QoS query.
The QoS timestamp changes with every message published,
this would force an update of the big DOM tree inside xmlBlaster
for every publish().

If i look at a typical qos:

    <qos>
       <sender>joe</sender>
       <rcvTimestamp millis='1013695176202'/>
       <expiration timeToLive='12000' />
       <isVolatile>false</isVolatile>
       <isDurable>true</isDurable>
       <forceUpdate>true</forceUpdate>
       <readonly>true</readonly>
    </qos>

it could be an approach to merge only more or less invariant
tags into the bigDom....


You should probably better put all queryable meta informations
into the key.
This will work with the current version.


Marcel


--
Marcel Ruff
mailto:ruff at swand.lake.de
http://www.lake.de/home/lake/swand/
http://www.xmlBlaster.org