Hierarchical Projects

Summary
=======

As of Kilo-1 release, keystone introduced a hierarchical structure of projects.
Aiming to improve user experience on this new organization, it is proposed to
support it on horizon, the OpenStack dashboard.

Motivation
==========

Real-world organizational structures tend to be hierarchical. As an example,
suppose an organization that have tens of departments hierarchically organized,
in which each sub department is a part of the parent department.

The best representation of this departmental hierarchy is in the form of a
tree, as they originally are structured, and not in a flat representation.

Aiming to enable such representation on OpenStack, the concept of hierarchical
projects was introduced by keystone, the OpenStack Identity service.

In order to improve user experience on hierarchical projects, it is proposed to
add support for such concept on horizon, the OpenStack dashboard.

Description
===========

The following features will be added on horizon:

a) Addition of Parent Project

Addition of parent project information when creating a project, allowing users
to build their project hierarchy. In addition, this information will be shown
when listing projects in admin mode.

b) Show Project Hierarchy

Show project hierarchy on projects panel, enabling users to view the existing
project hierarchy.

c) Use Project in Hierarchy

List project hierarchy on project selector dropdown, making it possible for
users to select the project in the hierarchy they want to use.

UX
==

Wireframes, Mocks, Videos and UI Markup
---------------------------------------

For the features that need to represent projects structure, it is proposed to
represent them as horizon currently does, but inserting the parent names for
each project, separated by a slash. See [1] as an example for feature c) Use
Project in Hierarchy.

a. Addition of Parent Project

Addition of a drop-down list on Create Project screen [2]. This list will
contain all the projects the user has access to, organized hierarchicaly.

When editing the project, the parent cannot be updated [3], since it is a
constraint adopted by keystone because it would be complex to edit the
hierarchy due to token revocations and quota checkings.

b. Show Project Hierarchy

The projects will be organized in an expandable tree view, honoring the project
hierarchy, according to the projects the user has access to, as shown in [4].

c. Use Project in Hierarchy

The select project drop-down list will be similar to the one proposed to be
added on the Create Project screen for selecting the parent project.

Testing
=======

There is no non-obvious effect that needs to be considered in tests.

Outside Dependencies
====================

The proposed features involve retrieval of the project hierarchy in which the
user has access to, the needed support on keystone service is already merged
and will be stable for Kilo release.

In addition, it will be required the following ongoing patch on
python-keystoneclient:

“Implements subtree_as_ids and parents_as_ids” [6], which enable the query of
projects IDs up and down the hierarchy as a structured dictionary.

In order to retrieve the project hierarchy, horizon will use the known
authorized projects for that user and the above operation, which provides the
full hierarchy structure in the form of ids.

Requirements Update Required
============================

Update python-keystoneclient requirement version.

Doc Impact
==========

Horizon documentation will be updated in order to expose to the user the new
features that will be introduced.

References
==========

[1] https://openstack.invisionapp.com/share/NT1KVIH4S#/screens/45149147
[2] http://invis.io/TE25TPE74
[3] http://invis.io/2H25TPQT6
[4] http://invis.io/KF25TOIZD
[5] https://openstack.invisionapp.com/share/NT1KVIH4S#/screens/44948197
[6] https://review.openstack.org/#/c/150078