Don't make calls to Keystone for authN if insufficient args are present

[Ajaya Agrawal]

Almost all OSC commands will try to authN with Keystone first.
If they succeed or fail, i.e.: `openstack user list` (succeeds) or `openstack role add` and `openstack server create` (fails, insufficient args)

Alternatively, when using old clients, `keystone user-role-add` or `nova boot` it errors out right away, rather than trying to authN with Keystone.

If we can do some basic argument checking before the command, it would definitely lower the amount of incoming requests to Keystone.

[Steve Martinelli (stevemar)]

hmm, not sure what the problem is, can you give some more info, it's working as expected for me:

$ openstack role add
usage: openstack role add [-h] [-f {shell,table,value}] [-c COLUMN]
                          [--max-width <integer>] [--prefix PREFIX] --project
                          <project> --user <user>
                          <role>
openstack role add: error: too few arguments

[Ajaya Agrawal (ajayaa)]

If you just type "openstack role add" and nothing else in arguments, some calls are being made to keystone. It should be caught at client level and an error should be printed out(which is being done btw). I think the calls are for authenticating the user whose credential is being used to call the above command.

So to reproduce it, just type "openstack role add" in cli and observer keystone logs.

[Steve Martinelli (stevemar)]

OK, I think you came across a larger possible optimization issue. So, you'll see the same keystone authN entries every time a call is made with openstackclient. If it succeeds or errors out, no matter what you're doing.

`openstack server create` will show the authN entries, same as `openstack user list` or `openstack role add`
This is likely caused by these lines of code here:
https://github.com/openstack/python-openstackclient/blob/master/openstackclient/shell.py#L67-L68

Alternatively, if you do `keystone user-role-add` or `nova boot` it errors out right away, rather than trying to authN with keystone.

I don't have a suggested fix at the moment, but it's definitely something to think about.

[Dean Troyer (dtroyer)]

FWIW, the upcoming changes to use the new keystoneclient.session.Session should help in this regard[0]. One reason you see differences in commands is due to the different API client libraries and their different implementations. Until they are either updated to also use Session or replaced this may not go away entirely.

[0] https://review.openstack.org/113046, https://review.openstack.org/106178

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/127735

[OpenStack Infra (hudson-openstack)]

Change abandoned by wanghong (<email address hidden>) on branch: master
Review: https://review.openstack.org/127735

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/129778
Committed: https://git.openstack.org/cgit/openstack/python-openstackclient/commit/?id=e063246b97a7f31a47aca0a5eb36d571f5df7236
Submitter: Jenkins
Branch: master

commit e063246b97a7f31a47aca0a5eb36d571f5df7236
Author: Dean Troyer <email address hidden>
Date: Mon Oct 20 18:53:10 2014 -0500

    Clean up shell authentication

    * Remove the auth option checks as the auth plugins will validate
      their own options
    * Move the initialization of client_manager to the end of
      initialize_app() so it is always called. Note that no attempts
      to actually authenticate occur until the first use of one of the
      client attributes in client_manager. This leaves
      initialize_clientmanager() (formerly uathenticate_user()) empty
      so remove it.
    * Remove interact() as the client_manager has already been created
      And there is nothing left.
    * prepare_to_run_command() is reduced to trigger an authentication
      attempt for the best_effort auth commands, currently the only
      one is 'complete'.
    * Add prompt_for_password() to ask the user to enter a password
      when necessary. Passed to ClientManager in a new kward pw_func.

    Bug: 1355838
    Change-Id: I9fdec9144c4c84f65aed1cf91ce41fe1895089b2