REPOZE.WHO ARCHITECTURE

For a quick overview, see the presentation in doc/_static/pyohio_2011.odp from a lightning talk I gave at PyOhio on 7/30/2011.

(For more information about repoze.who, see http://docs.repoze.org/who/1.0)

Classifiers - Determines what type of request is being sent, and how to classify the request so that identifiers can handle it.
Examples: brower, xmlrpc, oauth


Identifiers - Defines how to identify a user from the submitted credentials.
Examples: auth_tkt (cookie), form, oauth


Challenger - Defines how to display a challenge to the user, requiring them to authenticate themselves.
Examples: browser, xmlrpc, oauth, etc.


Metadata - Supplements the identity with additional data
Examples: Email address, first name, last name, groups, roles, permissions, etc.


REPOZE.WHAT (v 1.0) is just a metadata provider.

Protectors:
These are functions that assert that the user meets the necessary criteria (predicates) to be served the request.  If the criteria is not met, a 401 response is returned by the app, and is handled by the repoze.who challenger.