Open Stack

David Chadwick wrote up an in depth API extension for Federation: 
https://review.openstack.org/#/c/39499
There is an abfab API proposal as well: 
https://review.openstack.org/#/c/42221/

After discussing this for a while, it dawned on me that Federation 
should not be something bolted on to Keystone, but rather that it was 
already central to the design.

The SQL Identity backend is a simple password store that collects users 
into groups.  This makes it an identity provider (IdP).
Now Keystone can register multiple LDAP servers as Identity backends.

There are requests for SAML and ABFAB integration into Keystone as well.

Instead of a "Federation API"  Keystone should take the key concepts 
from the API and make them core concepts.  What would this mean:

1.  Instead of "method": "federation" "protocol": "abfab"  it would be 
"method": "abfab",
2.  The rules about multiple round trips (phase)  would go under the 
"abfab" section.
3.  There would not be a "protocol_data" section but rather that would 
be the "abfab" section as well.
4.  Provider ID would be standard in the method specific section.

One question that has come up has been about Providers, and whether they 
should be considered endpoints in the Catalog.  THere is a couple issues 
wiuth this:  one is that they are not something managed by OpenStack, 
and two is that they are not necessarily Web Protocols.  As such, 
Provider should probably be First class citizen.  We already have LDAP  
handled this way, although not as an enumerated entity.  For the first 
iteration, I would like to see ABFAB, SAML, and any other protocols we 
support done the same way as LDAP:  a deliberate configuration option 
for Keystone that will require a config file change.

David and I have discussed this in a side conversation, and agree that 
it requires wider input.