How to get parent tag while using XPaths in xml.etree.elementree with python 2.6.4

Question

I am newbie to this forum.

I am trying to retrieve data from xml.etree.cElementTree.

i have the following code

Code Snippet

import xml.etree.cElementTree as ET

xmldata ="""
<pipeline>
    <ep_150>
        <stage name="lay" longname="layout" department="layout" process="production">
            <review name="R1" reviewer="sridhar reddy" role="supervisor" id="p1234">
            </review>
        </stage>
        <stage name="lip" longname="lipsync" department="lipsync" process="production">
            <review name="R2" reviewer="someone" role="supervisor" id="p2345">
            </review>
        </stage>
        <stage name="blk" longname="blocking" department="animation" process="production">
            <review name="R3" reviewer="sudeepth" role="supervisor" id="p4645" dependson='R1'>
            </review>
            <review name="R4" reviewer="chandu" role="director" id="p5678">
            </review>
        </stage>
        <stage name="pri" longname="primary" department="animation" process="production">
            <review name="R5" reviewer="sudeepth" role="supervisor" id="p4645" style="dep" >
            </review>
            <review name="R6" reviewer="sudeepth" role="bld_supervisor" id="p2556" style="dep">
            </review>
        </stage>
        <stage name="sec" longname="secondary" department="animation" process="production">
            <review name="R7" reviewer="sha" role="supervisor" id="p1234" style="dep">
            </review>
            <review name="R8" reviewer="chandu" role="director" id="p5678">
            </review>
        </stage>
    </ep_150>
</pipeline>
"""
root = ET.fromstring(xmldata)

stages = root.findall("./ep_150/stage")

print 'Stages in animation department....\n'

for stage in stages:

    if stage.attrib['department']=='animation':
        print stage.attrib['name']

review = root.findall("./ep_150/stage/review")        

print '\n\nreviews for id=p4645\n'

for rev in review:

    if rev.attrib['id']=='p4645':
        print (rev.attrib['name'])

with the above code i am getting the result as below

Stages in animation department....

blk

pri

sec

reviews for id=p4645

R3

R5

But i need the output for second half as

reviewes for id=p4645

blk - R3

pri - R5

i.e, i need the parent tag of the element

Answer 1

The children don't know about their parents but the parents know about their children so you have to structure your code accordingly :-

stages = root.findall("./ep_150/stage")        

print '\n\nreviews for id=p4645\n'

for stage in stages:
    for rev in stage.findall('review'):
        if rev.attrib['id']=='p4645':
            print stage.attrib['name'], rev.attrib['name']

See http://effbot.org/zone/element.htm#accessing-parents

Unrelated to the answer. You can move those if's inside the findall argument if you like :-

root = ET.fromstring(xmldata)

stages = root.findall("./ep_150/stage[@department='animation']")

print 'Stages in animation department....\n'

for stage in stages:
    print stage.attrib['name']

stages = root.findall("./ep_150/stage")        

print '\n\nreviews for id=p4645\n'

for stage in stages:
    for rev in stage.findall("review[@id='p4645']"):
        print stage.attrib['name'], rev.attrib['name']