searching an XML doc

[grflanagan]

On Jan 15, 9:33 pm, Gowri <gowr... at gmail.com> wrote:
> Hello,
>
> I've been reading about ElementTreee and ElementPath so I could use
> them to find the right elements in the DOM. Unfortunately neither of
> these seem to offer XPath like capabilities where I can find elements
> based on tag, attribute values etc. Are there any libraries which can
> give me XPath like functionality?
>
> Thanks in advance

Create your query like:

ns0 = '{http://a.b.com/phedex}'

query = '%srequest/%sstatus' % (ns0, ns0)

Also, although imperfect, some people have found this useful:

http://gflanagan.net/site/python/utils/elementfilter/elementfilter.py.txt

[CODE]

test = '''<phedexData xmlns="http://a.b.com/phedex"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://a.b.com/phedex requests.xsd">
        <!--  Low priority replication request -->
        <request id="1234" last_update="1060199000.0">
                <status>
                        <approved>T1_RAL_MSS</approved>
                        <approved>T2_London_ICHEP</approved>
                        <disapproved>T2_Southgrid_Bristol</
disapproved>
                        <pending/>
                        <move_pending/>
                </status>
                <subscription open="1" priority="0" type="replicate">
                        <items>
                                <dataset>/PrimaryDS1/ProcessedDS1/
Tier</dataset>
                                        <block>/PrimaryDS2/
ProcessedDS2/Tier/block</block>
                        </items>
                </subscription>
        </request>
</phedexData>
'''

from xml.etree import ElementTree as ET

root = ET.fromstring(test)

ns0 = '{http://a.b.com/phedex}'

from rattlebag.elementfilter import findall, data

#http://gflanagan.net/site/python/utils/elementfilter/
elementfilter.py.txt

query0 = '%(ns)srequest/%(ns)sstatus' % {'ns': ns0}
query1 = '%(ns)srequest/%(ns)ssubscription[@type=="replicate"]/%
(ns)sitems' % {'ns': ns0}
query2 = '%(ns)srequest[@id==1234]/%(ns)sstatus/%(ns)sapproved' %
{'ns': ns0}

print 'With ElementPath: '
print root.findall(query0)
print
print 'With ElementFilter:'
for query in [query0, query1, query2]:
    print
    print '+'*50
    print 'query: ', query
    print
    for item in findall(root, query):
        print 'item: ', item
        print 'xml:'
        ET.dump(item)

print '-'*50
print
print 'approved: ', data(root, query2)

[/CODE]

[OUTPUT]
With ElementPath:
[<Element {http://a.b.com/phedex}status at b95ad0>]

With ElementFilter:

++++++++++++++++++++++++++++++++++++++++++++++++++
query:  {http://a.b.com/phedex}request/{http://a.b.com/phedex}status

item:  <Element {http://a.b.com/phedex}status at b95ad0>
xml:
<ns0:status xmlns:ns0="http://a.b.com/phedex">
                        <ns0:approved>T1_RAL_MSS</ns0:approved>
                        <ns0:approved>T2_London_ICHEP</ns0:approved>
                        <ns0:disapproved>T2_Southgrid_Bristol</
ns0:disapproved>
                        <ns0:pending />
                        <ns0:move_pending />
                </ns0:status>


++++++++++++++++++++++++++++++++++++++++++++++++++
query:  {http://a.b.com/phedex}request/{http://a.b.com/
phedex}subscription[@type
=="replicate"]/{http://a.b.com/phedex}items

item:  <Element {http://a.b.com/phedex}items at b95eb8>
xml:
<ns0:items xmlns:ns0="http://a.b.com/phedex">
                                <ns0:dataset>/PrimaryDS1/ProcessedDS1/
Tier</ns0:
dataset>
                                        <ns0:block>/PrimaryDS2/
ProcessedDS2/Tier
/block</ns0:block>
                        </ns0:items>


++++++++++++++++++++++++++++++++++++++++++++++++++
query:  {http://a.b.com/phedex}request[@id==1234]/{http://a.b.com/
phedex}status/
{http://a.b.com/phedex}approved

item:  <Element {http://a.b.com/phedex}approved at b95cd8>
xml:
<ns0:approved xmlns:ns0="http://a.b.com/phedex">T1_RAL_MSS</
ns0:approved>

item:  <Element {http://a.b.com/phedex}approved at b95cb0>
xml:
<ns0:approved xmlns:ns0="http://a.b.com/phedex">T2_London_ICHEP</
ns0:approved>

--------------------------------------------------

approved:  ['T1_RAL_MSS', 'T2_London_ICHEP']
INFO     End logging.
[/OUTPUT]