Expose container filters via API

[hongbin]

Description
===========
Right now, in DB layer, we support to filter containers with certain attributes. In particular, we support filter containers by attributes such as name, image, project_id, status, etc. [1]. It is better to expose this filter via REST API level. For example:

  GET /v1/containers?project_id=<my_project_id>

This should return a list of containers in particular project.

Implementation
==============
At zun/api/controllers/v1/containers.py , method 'get_all', populate the 'filters' from query parameter provided by users. For example (UNTESTED),

        filters = {}
        for filter_key in container_allowed_filters:
            if filter_key in kwargs:
                filter_value = kwargs[filter_key]
                filters[filter_key] = filter_value
        ...
        containers = objects.Container.list(context,
                                            limit,
                                            marker_obj,
                                            sort_key,
                                            sort_dir,
                                            filters=filters)

Reference
=========
[1] https://github.com/openstack/zun/blob/master/zun/db/sqlalchemy/api.py#L132

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/546098

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/546098
Committed: https://git.openstack.org/cgit/openstack/zun/commit/?id=00916cfdffe8d10ab6767a2a398743e477b6ea07
Submitter: Zuul
Branch: master

commit 00916cfdffe8d10ab6767a2a398743e477b6ea07
Author: deepak_mourya <email address hidden>
Date: Tue Feb 20 15:32:28 2018 +0530

    Expose container filters via API

    Right now, in DB layer, we support to filter containers
    with certain attributes. In particular, we support
    filter containers by attributes such as name, image,
    project_id, status, etc. [1]. It is better to expose this
    filter via REST API level. For example:

      GET /v1/containers?project_id=<my_project_id>

    This should return a list of containers in particular project.

    [1] https://github.com/openstack/zun/blob/master/zun/db/sqlalchemy/api.py#L132

    Change-Id: I599a9f48a966d564da718b97bdad7cfac6ae4dfe
    Closes-Bug: #1750208

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/zun 2.0.0 release.