openstack: novaclient Python API not working

Question

Trying to follow a simple tutorial for the openstack python API I found at http://docs.openstack.org/developer/python-novaclient/api.html but doesn't seem to be working. When I try to run

nova.servers.list()

or

nova.flavors.list()

from the tutorial on the python interpreter, I get following error:

  File "<stdin>", line 1, in <module>
  File "/usr/lib/python2.7/dist-packages/novaclient/v2/servers.py", line 617, in list
    return self._list("/servers%s%s" % (detail, query_string), "servers")
  File "/usr/lib/python2.7/dist-packages/novaclient/base.py", line 64, in _list
    _resp, body = self.api.client.get(url)
  File "/usr/lib/python2.7/dist-packages/novaclient/client.py", line 440, in get
    return self._cs_request(url, 'GET', **kwargs)
  File "/usr/lib/python2.7/dist-packages/novaclient/client.py", line 399, in _cs_request
    self.authenticate()
  File "/usr/lib/python2.7/dist-packages/novaclient/client.py", line 569, in authenticate
    self._v2_auth(auth_url)
  File "/usr/lib/python2.7/dist-packages/novaclient/client.py", line 634, in _v2_auth
    return self._authenticate(url, body)
  File "/usr/lib/python2.7/dist-packages/novaclient/client.py", line 647, in _authenticate
    **kwargs)
  File "/usr/lib/python2.7/dist-packages/novaclient/client.py", line 392, in _time_request
    resp, body = self.request(url, method, **kwargs)
  File "/usr/lib/python2.7/dist-packages/novaclient/client.py", line 386, in request
    raise exceptions.from_response(resp, body, url, method)
novaclient.exceptions.NotFound: The resource could not be found. (HTTP 404)

I'm using the same credentials as admin_openrc.sh, which works. Can't figure out what might be the problem.

Answer 1

Solved the issue: not sure why, openstack complained of missing user domain in auth (don't remember the exactly message error). Couldn't find how to inform user domain in nova, but I do found it on keystone!

from keystoneclient.auth.identity import v3
from keystoneclient import session
from keystoneclient.v3 import client
auth_url = 'http://10.37.135.89:5000/v3/'
username = 'admin'
user_domain_name = 'Default'
project_name = 'admin'
project_domain_name = 'Default'
password = '123456'
auth = v3.Password(auth_url=auth_url,
                   username=username,
                   password=password,
                   project_id='d5eef1aae54742e787d0653eea57254b',
                   user_domain_name=user_domain_name)
sess = session.Session(auth=auth)
keystone = client.Client(session=sess)
keystone.projects.list()

and after that I used keystone for authenticating in nova:

from novaclient import client
nova = client.Client(2, session=keystone.session)
nova.flavors.list()

Some usefull links that I used for this answer:

http://docs.openstack.org/developer/python-keystoneclient/authentication-plugins.html http://docs.openstack.org/developer/python-keystoneclient/using-api-v3.html http://docs.openstack.org/developer/python-novaclient/api.html

Answer 2

From your description, CLI works fine but script/interpreter fail, so it definitely because you initialize the novaclient.client.Client in a wrong way.

The usage of novaclient.client.Client depends on what version you are using, but your question doesn't provide such information, so currently I cannot provide an example for you, you can check it by run command 'nova --version'.

you can get help from developer documents for python-novaclient http://docs.openstack.org/developer/python-novaclient/api.html

Remember that, it is a good practice to use keyword argument instead of normal argument, which means

nc = client.Client(version=2, user='admin', password='password',
                   project_id='12345678', auth_url='http://127.0.0.1:5000')

is encouraged, it will expose problem when you try to do something in a wrong way.

Answer 3

You're using the python-novaclient as a library and it was never designed to be used that way. It's a CLI that people unfortunately use as a library.

Give the official Python OpenStack SDK a try.

pip install openstacksdk

The code for listing servers or flavors.

import sys

from openstack import connection
from openstack import profile
from openstack import utils

utils.enable_logging(True, stream=sys.stdout)

prof = profile.Profile()
prof.set_region(prof.ALL, 'RegionOne')

conn = connection.Connection(
    auth_url='http://my.openstack.com:5000/v2.0',
    profile=prof,
    username='demo',
    project_name='demo',
    password='demo')

for server in conn.compute.servers():
    print(server)

for flavor in conn.compute.flavors():
    print(flavor)

More info that might be helpful too:

• http://python-openstacksdk.readthedocs.org/en/latest/users/guides/compute.html
• https://pypi.python.org/pypi/openstacksdk