AttributeEnumeration model calls break enrollment flow plugins

Commit 1460d924189b861376f05a7880a3cfcc7f01603a, available for browsing at

https://github.com/Internet2/comanage-registry/commit/1460d924189b861376f05a7880a3cfcc7f01603a

introduced changes to a number of files in order to fix issues with AttributeEnumeration.

In particular the commit added the model AttributeEnumeration in the $uses array() for the CoPetitionsController:

// When using additional models, we must also specify our own

  public $uses = array(

    'CoPetition',

    'AttributeEnumeration',

    'CmpEnrollmentConfiguration',

    'OrgIdentitySource'

  );

This allows code in the beforeRender() function such as

$supportedEnumAttrs = $this->AttributeEnumeration->supportedAttrs();

The problem is that most enrollment flow plugins will extend CoPetitionsController and so inherit the beforeRender() function. If the plugin has a controller and anything is rendered (such as a form to consume an email verification code) then when beforeRender() is called as part of the plugin execution then the variable $this refers to the name of plugin controller class and not CoPetitionsController, and hence

$this->AttributeEnumeration

resolves to null instead of the AttributeEnumeration class and a call to supportedAttrs() fails.

Either the core code should load and then invoke the AttributeEnumeration model in some other way, or the documentation for Enrollment Flow Plugins at

https://spaces.at.internet2.edu/display/COmanage/Enrollment+Flow+Plugins

needs to be updated to include "AttributeEnumeration" in the $uses and additionally the 4.4.0 release notes at

https://spaces.at.internet2.edu/display/COmanage/Upgrading+Registry+to+v4.4.0

so that deployers know that 4.4.0 will break enrollment flows until the enrollment flow plugin is evolved.