Add an attachments API
This includes a new attachment controller and shell
commands.  To use you'll need to set your api version
    `export OS_VOLUME_API_VERSION=3.27`

Now you can do things like attach a volume (cinders part at least):
    `cinder attachment-create --connect True ......`

List/show/delete existing attachments:
    `cinder attachment-list`
    `cinder attachment-show <attachment-id>`
    `cinder attachment-delete <attachemnt-id>`

Change-Id: I2c463f0910b6c9e37502869b7ec33073f12939f1

Because of 'start_version' parameter in decorator here [0]
we won't have metadata attr in args using api versions from 3.0 to 3.21.

This patch changes getting metadata from args logic for compatibility with
the api versions 3.0 - 3.21.

[0] - https://github.com/openstack/python-cinderclient/blob/b73b3932404c4645e05aaefae5502ab2304a5334/cinderclient/v3/shell.py#L1237

Change-Id: I4aa099556c57c49e9ad74fe80e5591d738cf3aa0
Closes-Bug: #1659561

After v3.10, cinder support filter volumes by group_id, this patch
support this feature for client side.

Change-Id: Ie7df4d8b81789fd36ca6f91d96a477c88e8d5a52
Partial-Implements: blueprint improvement-to-query-consistency-group-detail

@utils.service_type was introduced with 'Initial split from
python-novaclient' commit and used for CLI. Now both Python and
Command-line APIs for each version  work well without this decorator.

Unused 'get_service_type' function is removed too.

'utils.retype_method' removed as well because everything works well
without it.

Change-Id: Ic2470d8ca9d581b7c47da8d7e6a414c3c78ad27a
Partial-Bug: #1643584
Related-Bug: #1621126

volume list filtered on image_metadata does not work as expected.
The filtering based on image_metadata depended on non existent
utility for extracting image_metadata.
Fixed the issue by calling appropriate utility module
for extracting image_metadata. Looks like a typo.

Change-Id: I13e78277fc1afd22d044bb49b6a5ccc00904228c
Closes-bug: #1657650

The snpapshot-list API for cinder gives a list of snapshots based
on certain criteria to the user. From microversion 3.22 onwards
the snapshot-list API has been enhanced to support snapshot list
filtering based on metadata of snapshots. The metadata is stored
as key-value pair for every snapshot.
With this commit cinder will be queried based on metadata key and
value specified in the API snaphot-list. All the snapshots which
match the key, value provided by the user along with any other
filter criteria will be returned.
Added the test cases for the CLI and web requests.

DocImpact: "Filters results by a metadata key and value pair.
Default=None." on cinder snapshot-list
APIImpact

Closes-bug: #1569554

Change-Id: Idec0d0d02e7956843f202508e32c023c3cafbb0f

Now v2 API uses code from v3. It's confusing and logically incorrect.
This patch makes v3 API as an extended version of v2.

The next patches related to this bug duplicated code between v1 and v2,
v2 and v3 will be removed.

Change-Id: I90a2b713556e91db69270a03ef6b798e08f93f90
Partial-Bug: #1643584

The unicode_key_value_to_string() function is designed to remove
extra 'u' in cinderclient cli output.
However this patch[1] bring the extra 'u' back.
Let's remove the extra 'u' again.

Closes-bug: #1615921
Closes-bug: #1606904

[1] https://review.openstack.org/#/c/342734/
Change-Id: I26f0ad7149f57e935953c2398ba90b7b3585e201

Change help about private volume types according to the implementation.

Change-Id: I59d811c4a6afb1a8162cf25ff1a734facbf68d8d
Related-Bug: #1637549