Add API input validation utility for openstack common

Registered by Rohit Karajgi

This is a feature request to enable openstack-common code in oslo to perform common input validations
across Openstack API.

Most of the validation of create resource API are scattered and duplicated, across Nova, Keystone, Cinder, Glance. Due to this, there is a lot of inconsistency in how the APIs respond to similar classes of input.

Refer: https://docs.google.com/file/d/0BwufSlaYow2GUUZJVlJYVGM2VVU/edit?usp=sharing

A utility in Oslo will enable common validation tasks such as:
* checking input length (based on min and max values)
* checking input well-formedness (say, based on an expected regex),
* raise appropriate exceptions wherever needed

This could go into a separate module like openstack/common/validation_utils.py

Also refer the discussion on Bug https://bugs.launchpad.net/nova/+bug/1206396

Blueprint information

Status:
Started
Approver:
Mark McLoughlin
Priority:
Undefined
Drafter:
None
Direction:
Needs approval
Assignee:
Tushar Patil
Definition:
New
Series goal:
None
Implementation:
Started
Milestone target:
None
Started by
Rohit Karajgi

Related branches

Sprints

Whiteboard

Ken'ichi started some work on this in WSME. See https://review.openstack.org/#/c/54249/ -- dhellmann

(?)

Work Items

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