wsgi.XMLDeserializer tries to access non existing attributes of xml node

[Tatyanka]

extract_text method of wsgi.XMLDeserializer tries to access "childNodes" attribute of "node" object which is supposed to be of type xml.etree.ElementTree.Element which in turn doesn't have such attribute. (https://github.com/openstack/quantum/blob/master/quantum/wsgi.py#L567)

The error seems to be caused by refactoring in this change (https://review.openstack.org/#/c/19998/) which replaced library for parsing xml from minidom to etree but left some calls to minidom unchanged.

Here is the trace, obtained by calling extract_text:

Error
Traceback (most recent call last):
  File "/usr/lib/python2.7/dist-packages/unittest2/case.py", line 340, in run
    testMethod()
  File "/home/repos/quantum/quantum/tests/unit/test_wsgi.py", line 658, in test_extract_text
    deserializer.extract_text(doc), 'test_child')
  File "/home/repos/quantum/quantum/wsgi.py", line 567, in extract_text
    if len(node.childNodes) == 1:
AttributeError: 'Element' object has no attribute 'childNodes'

[Ante Karamatić (ivoks)]

Hm... test_extract_text() doesn't exist anywhere in quantum source. In fact, quantum/tests/unit/test_wsgi.py has only 373 lines. Am I missing something?

[Tatyanka (tatyana-leontovich)]

Actually you are write, at this moment I've try to add it (in scope of https://review.openstack.org/#/c/20692/), but can't accordingly to this issue. I can provide to you the test, if it will be helpful

[Salvatore Orlando (salvatore-orlando)]

Tatyana - what's the outcome of your triaging?
From my perspective it seems extract_test is an unused method and should therefore be removed.
Indeed there's now similar logic in wsgy.py, lines 523-535.

If that is confirmed, I suggest lowering the priority of this bug, and fixing it by simply removing the method.

[Tatyanka (tatyana-leontovich)]

Salvatore,
I absolutely agree with you. There is as minimum four unused method in wsgi module, that ate broken. An as you've written, may be, we can remove it. My point is that there should not be broken code in this module. Unfortunaly I can not confirm, can we remove these methods or not. And against, agree with you, that we need receive such confirmation.

[Salvatore Orlando (salvatore-orlando)]

From my perspective, you have my +2 if you want to remove this method and any other bit of unused code you found in the wsgi module.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/21631

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/21631
Committed: http://github.com/openstack/quantum/commit/6f2b1899610d58c401a64776f936fbd300b662bd
Submitter: Jenkins
Branch: master

commit 6f2b1899610d58c401a64776f936fbd300b662bd
Author: Tatyana Leontovich <email address hidden>
Date: Mon Feb 11 12:17:12 2013 +0200

    Unused methods in quantum.wsgi clean up

    Remove broken unused methods:
    * wsgi.XMLDeserializer.extract_text,
    * wsgi.XMLDeserializer.find_first_child_named,
    * wsgi.XMLDeserializer.find_first_child_named,
    * wsgi.XMLDictSerializer._create_link_nodes.

    Change-Id: If00af68683571285adb0516d8fc36790bd83ffa5
    Fixes: bug #1119262