Share group types are types for share groups just like share types for
shares<shared_file_systems_share_types>. A group type is
associated with group specs similar to the way extra specs are
associated with a share type.

A share group type aids the scheduler to filter or choose back ends
when you create a share group and to set any backend specific parameters
on the share group. Any driver that can perform a group operation in an
advantaged way may report that as a group capability, such as:

• Ordered writes
• Consistent snapshots
• Group replication
• Group backup

Share group types may contain group specs corresponding to the group
capabilities reported by the backends. A group capability applies across
all the shares inside the share group, for example, a backend may
support consistent_snapshot_support, and
using this group type extra spec in the group type will allow scheduling
share groups onto that backend. Any time a snapshot of the group is
initiated, a crash consistent simultaneous snapshot of all the
constituent shares is taken. Shares in a share group may each have
different share types because they can each be on separate pools, have
different capabilities and perhaps end users can even be billed
differently for using each of them. To allow for this possibility, one
or more share types can be associated with a group type. The admin also
specifies which share type(s) a given group type may contain. At least
one share type must be provided to create a share group type. When an
user creates a share group, the scheduler creates the group on one of
the backends that match the specified share type(s) and share group
type.

In the Shared File Systems configuration file
manila.conf, the administrator can set the share group type
used by default for the share group creation.

To create a share group type, use manila share-group-type-create command as:

manila share-group-type-create [--is_public <is_public>]
                               [--group-specs [<key=value> [<key=value> ...]]]
                               <name> <share_types>

Where the name is the share group type name and
--is_public defines the level of the visibility for the
share group type. One share group can include multiple
share_types. --group-specs are the extra
specifications used to filter back ends.

Administrators can create share group types with these extra
specifications for the back ends filtering. An administrator can use the
policy.yaml file to grant permissions for share group type
creation with extra specifications to other roles.

You set a share group type to private or public and manage the access<share_group_type_access> to
the private share group types. By default a share group type is created
as publicly accessible. Set --is_public to
False to make the share group type private.

Share group type operations

To create a new share group type you need to specify the name of the
new share group type and existing share types. The new share group type
can also be public. One share group can include multiple share
types.

$ manila share-group-type-create group_type_for_cg default_share_type --is_public True
+------------+--------------------------------------+
| Property   | Value                                |
+------------+--------------------------------------+
| is_default | -                                    |
| ID         | cfe42f20-d13e-4348-9370-f0763e426db3 |
| Visibility | public                               |
| Name       | group_type_for_cg                    |
+------------+--------------------------------------+

$ manila share-group-type-list
+--------------------------------------+-------------------+------------+------------+
| ID                                   | Name              | visibility | is_default |
+--------------------------------------+-------------------+------------+------------+
| cfe42f20-d13e-4348-9370-f0763e426db3 | group_type_for_cg | public     | -          |
+--------------------------------------+-------------------+------------+------------+

You can set or unset extra specifications for a share group type
using manila share-group-type-key <share_group_type> set
<key=value> command.

$ manila share-group-type-key group_type_for_cg set consistent_snapshot_support=host

It is also possible to view a list of current share group types and
extra specifications:

$ manila share-group-type-specs-list
+--------------------------------------+-------------------+------------------------------------+
| ID                                   | Name              | all_extra_specs                    |
+--------------------------------------+-------------------+------------------------------------+
| cfe42f20-d13e-4348-9370-f0763e426db3 | group_type_for_cg | consistent_snapshot_support : host |
+--------------------------------------+-------------------+------------------------------------+

Use manila share-group-type-key <share_group_type> unset <key>
to unset an extra specification.

A public or private share group type can be deleted with the manila share-group-type-delete <share_group_type>
command.

Share group type access

You can manage access to a private share group type for different
projects. Administrators can provide access, revoke access, and retrieve
information about access for a specified private share group.

Create a private group type:

$ manila share-group-type-create my_type1 default_share_type --is_public False
+------------+--------------------------------------+
| Property   | Value                                |
+------------+--------------------------------------+
| is_default | -                                    |
| ID         | f57cf3db-2503-4c0f-915c-4f1335d95465 |
| Visibility | private                              |
| Name       | my_type1                             |
+------------+--------------------------------------+

Grant access to created private type for a demo and alt_demo projects
by providing their IDs:

$ manila share-group-type-access-add my_type1 d8f9af6915404114ae4f30668a4f5ba7
$ manila share-group-type-access-add my_type1 e4970f57f1824faab2701db61ee7efdf

To view information about access for a private share, manila type-access-list my_type1:

$ manila type-access-list my_type1
+----------------------------------+
| Project_ID                       |
+----------------------------------+
| d8f9af6915404114ae4f30668a4f5ba7 |
| e4970f57f1824faab2701db61ee7efdf |
+----------------------------------+

After granting access to the share group type, the target project can
see the share group type in the list, and create private share
groups.

To deny access for a specified project, use manila share-group-type-access-remove <share_group_type> <project_id>
command.

$ manila share-group-type-access-remove my_type1 e4970f57f1824faab2701db61ee7efdf