Add messages resource for sending errors to users

Registered by Alex Meade

For quite some time, OpenStack services have wanted to be able to send messages to API end users (by user I do not mean the Operator, but the User that is interacting with the client).

At the Mitaka Cinder midcycle (https://etherpad.openstack.org/p/mitaka-cinder-midcycle-user-notifications), we decided to begin solving this problem by adding a /messages resource to the api in order for end-users to query for more information about errors.

Blueprint information

Status:
Complete
Approver:
Sean McGinnis
Priority:
High
Drafter:
Alex Meade
Direction:
Approved
Assignee:
Alex Meade
Definition:
Superseded
Series goal:
Accepted for newton
Implementation:
Unknown
Milestone target:
milestone icon newton-2
Completed by
Sean McGinnis

Related branches

Sprints

Whiteboard

Gerrit topic: https://review.openstack.org/#q,topic:bp/user-messages,n,z

Addressed by: https://review.openstack.org/274958
    User facing error messages

Gerrit topic: https://review.openstack.org/#q,topic:bp/summarymessage,n,z

Addressed by: https://review.openstack.org/273938
    User facing error Summary Messages

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Work Items

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