Hello, The code that we use in engine-setup to modify JBoss AS XML configuration files uses the following pattern: datasourceStr = ''' <datasource ...> ... </datasource> ''' xmlObj.addNodes("//datasource:subsystem/datasource:datasources", datasourceStr) This looks correct but is in fact generating a incorrect XML document, as the tags being added are not associated to a namespace. The resulting XML file will be correct, but the temporary representation in memory is not. This causes problems if you later, before writing out the modified file, try to use xpath expressions matching the added nodes: there will be no match. I would suggest that we change the pattern to something like this: datasourceStr = ''' <any_dummy_tag xmlns="urn:jboss:domain:datasources:1.0"> <datasource ...> ... </datasource> </any_dummy_tag> ''' datasourceNodes = libxml2.parseDoc(datasourceStr).getRootElement().children xmlObje.addNodes("//datasource:subsystem/datasource:datasources", datasourceNodes) This way both the representation in memory and the resulting file are correct. Le me know what you think.

Regards, Juan Hernandez -- Dirección Comercial: C/Jose Bardasano Baos, 9, Edif. Gorbea 3, planta 3ºD, 28016 Madrid, Spain Inscrita en el Reg. Mercantil de Madrid – C.I.F. B82657941 - Red Hat S.L. _______________________________________________ Engine-devel mailing list Engine-devel(a)ovirt.org http://lists.ovirt.org/mailman/listinfo/engine-devel

Hello, The code that we use in engine-setup to modify JBoss AS XML configuration files uses the following pattern: datasourceStr = ''' <datasource ...> ... </datasource> ''' xmlObj.addNodes("//datasource:subsystem/datasource:datasources", datasourceStr) This looks correct but is in fact generating a incorrect XML document, as the tags being added are not associated to a namespace. The resulting XML file will be correct, but the temporary representation in memory is not. This causes problems if you later, before writing out the modified file, try to use xpath expressions matching the added nodes: there will be no match. I would suggest that we change the pattern to something like this: datasourceStr = ''' <any_dummy_tag xmlns="urn:jboss:domain:datasources:1.0"> <datasource ...> ... </datasource> </any_dummy_tag> ''' datasourceNodes = libxml2.parseDoc(datasourceStr).getRootElement().children xmlObje.addNodes("//datasource:subsystem/datasource:datasources", datasourceNodes) This way both the representation in memory and the resulting file are correct. Le me know what you think.

On 04/12/2012 07:18 AM, Daniel Veillard wrote: > On Tue, Apr 10, 2012 at 01:54:51PM +0200, Juan Hernandez wrote: >> Hello, >> >> The code that we use in engine-setup to modify JBoss AS XML >> configuration files uses the following pattern: >> >> datasourceStr = ''' >> <datasource ...> >> ... >> </datasource> >> ''' >> >> xmlObj.addNodes("//datasource:subsystem/datasource:datasources", >> datasourceStr) >> >> This looks correct but is in fact generating a incorrect XML document, >> as the tags being added are not associated to a namespace. The resulting >> XML file will be correct, but the temporary representation in memory is >> not. This causes problems if you later, before writing out the modified >> file, try to use xpath expressions matching the added nodes: there will >> be no match. >> >> I would suggest that we change the pattern to something like this: >> >> datasourceStr = ''' >> <any_dummy_tag xmlns="urn:jboss:domain:datasources:1.0"> >> <datasource ...> >> ... >> </datasource> >> </any_dummy_tag> >> ''' >> datasourceNodes = libxml2.parseDoc(datasourceStr).getRootElement().children >> >> xmlObje.addNodes("//datasource:subsystem/datasource:datasources", >> datasourceNodes) >> >> This way both the representation in memory and the resulting file are >> correct. >> >> Le me know what you think. > > I think it's dangerous to move nodes from one document to another > especially if there is namespaces (I assume you're operating in an > environment on top of libxml2 as I saw a reference to it ;-) > > For libxml2 there is an API in C: > http://xmlsoft.org/html/libxml-parser.html#xmlParseInNodeContext > which could do what you expect. Maybe there is a binding/wrapper > available you could use. Thanks Daniel, that looks certainly better/easier than what I am proposing. We use libxml2-python, but I can't locate that method there. Do you know if it is possible to use it from python?