using deprecated message attribute of the Exception class

[Jin Li]

The message attribute of the Exception class has been deprecated after the python 2.7 : https://www.python.org/dev/peps/pep-0352/. Calling Exception.message will cause python 3.4 to fail.

Below is an example in the gluon/particleGenerator/cli.py module, the do_post function fails a uni test case which triggers it to call the e.message.

The do_post function:
def do_post(url, values):
    resp = post(url, json=values)
    if resp.status_code != 200 and resp.status_code != 201:
        raise exc.GluonClientException('Bad return status %d'
                                       % resp.status_code,
                                       status_code=resp.status_code)
    try:
        rv = json.loads(resp.content)
    except Exception as e:
        raise exc.MalformedResponseBody(reason="JSON unreadable: %s on %s"
                                               % (e.message, resp.content))
    return rv

uni test case:
    @mock.patch.object(cli, "post")
    def test_do_post_badRspBody(self, mock_post):
        rsp = mock.Mock()
        rsp.status_code = 200
        rsp.content = "response in wrong json format"
        mock_post.return_value = rsp
        jsonValue = {"foo": "bar"}
        self.assertRaises(exc.MalformedResponseBody,
                          cli.do_post,
                          'www.gluonURL.net',
                          jsonValue)

Python34 test result with error:
2016-12-03 02:12:33.808892 | ======================================================================
2016-12-03 02:12:33.808914 | FAIL: gluon.tests.particleGenerator.test_cli.CliTestCase.test_do_post_badRspBody
2016-12-03 02:12:33.808923 | tags: worker-7
2016-12-03 02:12:33.808944 | ----------------------------------------------------------------------
2016-12-03 02:12:33.808957 | Empty attachments:
2016-12-03 02:12:33.808965 | stderr
2016-12-03 02:12:33.808973 | stdout
2016-12-03 02:12:33.808978 |
2016-12-03 02:12:33.808991 | Traceback (most recent call last):
2016-12-03 02:12:33.809019 | File "/home/jenkins/workspace/gate-gluon-python34/gluon/particleGenerator/cli.py", line 116, in do_post
2016-12-03 02:12:33.809032 | rv = json.loads(resp.content)
2016-12-03 02:12:33.809052 | File "/usr/lib/python3.4/json/__init__.py", line 318, in loads
2016-12-03 02:12:33.809065 | return _default_decoder.decode(s)
2016-12-03 02:12:33.809096 | File "/usr/lib/python3.4/json/decoder.py", line 343, in decode
2016-12-03 02:12:33.809115 | obj, end = self.raw_decode(s, idx=_w(s, 0).end())
2016-12-03 02:12:33.809135 | File "/usr/lib/python3.4/json/decoder.py", line 361, in raw_decode
2016-12-03 02:12:33.809156 | raise ValueError(errmsg("Expecting value", s, err.value)) from None
2016-12-03 02:12:33.809173 | ValueError: Expecting value: line 1 column 1 (char 0)
2016-12-03 02:12:33.809179 |
2016-12-03 02:12:33.809199 | During handling of the above exception, another exception occurred:
2016-12-03 02:12:33.809205 |
2016-12-03 02:12:33.809217 | Traceback (most recent call last):
2016-12-03 02:12:33.809250 | File "/home/jenkins/workspace/gate-gluon-python34/.tox/py34/lib/python3.4/site-packages/mock/mock.py", line 1305, in patched
2016-12-03 02:12:33.809264 | return func(*args, **keywargs)
2016-12-03 02:12:33.809298 | File "/home/jenkins/workspace/gate-gluon-python34/gluon/tests/particleGenerator/test_cli.py", line 204, in test_do_post_badRspBody
2016-12-03 02:12:33.809307 | jsonValue)
2016-12-03 02:12:33.809342 | File "/home/jenkins/workspace/gate-gluon-python34/.tox/py34/lib/python3.4/site-packages/testtools/testcase.py", line 485, in assertRaises
2016-12-03 02:12:33.809357 | self.assertThat(our_callable, matcher)
2016-12-03 02:12:33.809392 | File "/home/jenkins/workspace/gate-gluon-python34/.tox/py34/lib/python3.4/site-packages/testtools/testcase.py", line 496, in assertThat
2016-12-03 02:12:33.809413 | mismatch_error = self._matchHelper(matchee, matcher, message, verbose)
2016-12-03 02:12:33.809449 | File "/home/jenkins/workspace/gate-gluon-python34/.tox/py34/lib/python3.4/site-packages/testtools/testcase.py", line 547, in _matchHelper
2016-12-03 02:12:33.809463 | mismatch = matcher.match(matchee)
2016-12-03 02:12:33.809499 | File "/home/jenkins/workspace/gate-gluon-python34/.tox/py34/lib/python3.4/site-packages/testtools/matchers/_exception.py", line 108, in match
2016-12-03 02:12:33.809516 | mismatch = self.exception_matcher.match(exc_info)
2016-12-03 02:12:33.809553 | File "/home/jenkins/workspace/gate-gluon-python34/.tox/py34/lib/python3.4/site-packages/testtools/matchers/_higherorder.py", line 62, in match
2016-12-03 02:12:33.809567 | mismatch = matcher.match(matchee)
2016-12-03 02:12:33.809601 | File "/home/jenkins/workspace/gate-gluon-python34/.tox/py34/lib/python3.4/site-packages/testtools/testcase.py", line 475, in match
2016-12-03 02:12:33.809611 | reraise(*matchee)
2016-12-03 02:12:33.809646 | File "/home/jenkins/workspace/gate-gluon-python34/.tox/py34/lib/python3.4/site-packages/testtools/_compat3x.py", line 16, in reraise
2016-12-03 02:12:33.809660 | raise exc_obj.with_traceback(exc_tb)
2016-12-03 02:12:33.809696 | File "/home/jenkins/workspace/gate-gluon-python34/.tox/py34/lib/python3.4/site-packages/testtools/matchers/_exception.py", line 101, in match
2016-12-03 02:12:33.809706 | result = matchee()
2016-12-03 02:12:33.809741 | File "/home/jenkins/workspace/gate-gluon-python34/.tox/py34/lib/python3.4/site-packages/testtools/testcase.py", line 1049, in __call__
2016-12-03 02:12:33.809760 | return self._callable_object(*self._args, **self._kwargs)
2016-12-03 02:12:33.809790 | File "/home/jenkins/workspace/gate-gluon-python34/gluon/particleGenerator/cli.py", line 119, in do_post
2016-12-03 02:12:33.809803 | % (e.message, resp.content))
2016-12-03 02:12:33.809829 | AttributeError: 'ValueError' object has no attribute 'message'

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/411003

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/411003
Committed: https://git.openstack.org/cgit/openstack/gluon/commit/?id=8c21b6a2e98315f22ffdbae511399ff441e4d131
Submitter: Jenkins
Branch: master

commit 8c21b6a2e98315f22ffdbae511399ff441e4d131
Author: JinLi <email address hidden>
Date: Wed Dec 14 15:42:33 2016 -0800

    Fix Exception.message deprecated error

    some places in our code still use Exception.message which has been
    deprecated after python2.6. and cause test cases to fail.
    Change it to Excepton.args[0] to fix this issue. Test cases for this
    change is in this patch: https://review.openstack.org/#/c/405689/

    Change-Id: I7ca0549847fa7f165a9c3bf1e2659c0572a13b6c
    Closes-Bug: #1648584