Introduce Oslo’s cliff as cli framework for Barbican

Introduce cliff as a cli framework for python-barbicanclient, and, as a result promote usage of common OpenStack libraries.

Problem Description

Currently the Barbican cli utilities (such as the migration script and even the python-barbicanclient itself) rely on the argparse library, yet, their current implementations do not provide sufficient information for their usage in production. Usage of “standard” libraries should be encouraged in order to make Barbican’s integration easier. On the other hand, subcommand help is lacking, and input is not properly validated.

Proposed Change

The proposal is to take into use cliff, which is a framework for building command line programs introduced by Oslo. This will enable Barbican’s scripts to have more standard outputs (akin to other OpenStack projects) and while moving the code to the new framework, better documentation will be added to the commands as part of the work.

Alternatives

The argparse library could still be used, yet, more input validation and documentation needs to be added.

Data model impact

None.

REST API impact

None.

Security impact

None for the Barbican server. Barbican client input though should be properly validated as part of the work.

Notifications impact

None.

Other end user impact

This will hopefully have a positive impact in the client’s usability, as the main focus of this work is to make it better.

Performance Impact

None.

Other deployer impact

This change takes immediate effect after it’s merged, and adds a dependency (which is cliff) to the python-barbicanclient.

Developer impact

If other developers are working with the client, it might affect their work, since the changes are potentially big.

Work Items

  • Replicate the current functionality of python-barbicanclient (with help messages and subcommands) to the new framework.
  • Complete missing sub-command help over the new framework.

Testing

Unit tests are assumed.

Documentation Impact

None.