Camel saxon Xquery : Misdeclaration of xmlns namespace - apache-camel

Question

I'm having a big problem that I can not understand.
i have a camel route that has a xquery transformation:
<transform>
<xquery>resource:file {{choregraphies.resources.directory}}/LINCASA1/xquery/getTypApr_request.xquery
</xquery>
</transform>
I put you inside the getTypApr_request.xquery file
xquery version "1.0";
declare namespace xs="http://www.w3.org/2001/XMLSchema";
declare namespace com="com.edfgdf.a21.business.impl";
declare variable $in.headers.prmId as xs:string external;
declare variable $in.headers.id as xs:string external;
<com:getTypApr>
<idClient>{$in.headers.id}</idClient>
<reference>{$in.headers.prmId}</reference>
</com:getTypApr>
Before, I was in camel 2.17 and Saxon 9.5.1-5, it works very well. I recently switched to Camel 2.21 and Saxon 9.8.0-8.
And now I see that I have an XqueryExpression in null. Camel returns to me:
 [Transform [XQuery xquery {[null]}]
I do not know what to do, could you help me
Thx
EDIT :
after research, my route starts with:
<routes xmlns="http://camel.apache.org/schema/spring">
Before, Xbuilder did'nt take into account the namespace of the road and now if, therefore, I have the error:
org.apache.camel.RuntimeExpressionException: java.lang.IllegalArgumentException: Misdeclaration of xmlns namespace
at org.apache.camel.component.xquery.XQueryBuilder.evaluate(XQueryBuilder.java:154) ~[camel-saxon-2.21.0.jar:2.21.0]
at org.apache.camel.component.xquery.XQueryBuilder.evaluate(XQueryBuilder.java:119) ~[camel-saxon-2.21.0.jar:2.21.0]
at org.apache.camel.processor.TransformProcessor.process(TransformProcessor.java:50) ~[camel-core-2.21.0.jar:2.21.0]
at org.apache.camel.processor.RedeliveryErrorHandler.process(RedeliveryErrorHandler.java:548) ~[camel-core-2.21.0.jar:2.21.0]
at org.apache.camel.processor.CamelInternalProcessor.process(CamelInternalProcessor.java:201) [camel-core-2.21.0.jar:2.21.0]
at org.apache.camel.processor.Pipeline.process(Pipeline.java:138) [camel-core-2.21.0.jar:2.21.0]
at org.apache.camel.processor.Pipeline.process(Pipeline.java:101) [camel-core-2.21.0.jar:2.21.0]
at org.apache.camel.processor.CamelInternalProcessor.process(CamelInternalProcessor.java:201) [camel-core-2.21.0.jar:2.21.0]
at org.apache.camel.component.seda.SedaConsumer.sendToConsumers(SedaConsumer.java:298) [camel-core-2.21.0.jar:2.21.0]
at org.apache.camel.component.seda.SedaConsumer.doRun(SedaConsumer.java:210) [camel-core-2.21.0.jar:2.21.0]
at org.apache.camel.component.seda.SedaConsumer.run(SedaConsumer.java:155) [camel-core-2.21.0.jar:2.21.0]
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) [na:1.8.0_162]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) [na:1.8.0_162]
at java.lang.Thread.run(Thread.java:748) [na:1.8.0_162]
Caused by: java.lang.IllegalArgumentException: Misdeclaration of xmlns namespace
at net.sf.saxon.query.StaticQueryContext.declareNamespace(StaticQueryContext.java:719) ~[Saxon-HE-9.8.0-8.jar:na]
at org.apache.camel.component.xquery.XQueryBuilder.initialize(XQueryBuilder.java:720) ~[camel-saxon-2.21.0.jar:2.21.0]
at org.apache.camel.component.xquery.XQueryBuilder.evaluateAsDOM(XQueryBuilder.java:183) ~[camel-saxon-2.21.0.jar:2.21.0]
at org.apache.camel.component.xquery.XQueryBuilder.evaluate(XQueryBuilder.java:144) ~[camel-saxon-2.21.0.jar:2.21.0]
... 13 common frames omitted

Answer 1

The error is reported by Saxon when Apache camel attempts to declare a namespace binding in which either (a) the prefix is "xmlns", or (b) the namespace URI is "http://www.w3.org/2000/xmlns/".
I have checked the 9.5 and 9.8 source code for the method StaticQueryContext.declareNamespace() and they appear to be identical: both report this error if this prefix or URI appears. So it doesn't appear to be a Saxon change that has caused the problem.
The prefix xmlns is used in declarations such as xmlns:p="my.uri". In DOM, such declarations are treated as attributes whose name has (prefix=xmlns, local-name=p, uri="http://www.w3.org/2000/xmlns/"). By contrast, in the XDM data model used by XQuery, this declaration is not considered to be an attribute node; it is a namespace node with name "p" and string value "my.uri", and there is never any namespace binding for the prefix "xmlns" or the URI "http://www.w3.org/2000/xmlns/". Section 4.13 of the XQuery 3.1 specification explicitly disallows this prefix or URI being used in a namespace declaration appearing in a query, which is why Saxon is throwing an error when StaticQueryContext.declareNamespace() is used with these values.
I've taken a look at the Camel source code at https://github.com/apache/camel/blob/master/components/camel-saxon/src/main/java/org/apache/camel/component/xquery/XQueryBuilder.java
and it seems plausible that Camel is declaring every namespace binding that it encounters in a DOM, but I would need a much deeper understanding of Camel to see exactly what's going on here.