CollaborationPolicyRecord - instantiate policy rules from the policy_…

…record

* Remove AppConfig, CollaborationPolicy registration/caching messiness
* Data migration ensures all valid policies are in the CollaborationPolicyRecord
* Instantiate the CollaborationPolicy directly from CollaborationPolicyRecord
(note: removes a layer of caching. possible speed hit)

mediathread/main/fixtures/sample_assignment.json

@@ -5,20 +5,6 @@
         "fields": {
             "body": "<p>The Columbia Center for New Media Teaching and Learning (CCNMTL) was founded at Columbia University in 1999 to enhance teaching and learning through the purposeful use of new media and technology. In partnership with faculty, the Center supports efforts ranging from basic course website management to advanced project development.&#160;<span class=\"caps\">CCNMTL&#160;</span>is committed to remaining a leader in the field of new media teaching and learning, engaging faculty, educators, librarians, partner institutions, and the community in the reinvention of education for the digital age.</p>\r\n<p>We are committed to ongoing evaluation of the efficacy of our work within the University.</p>\r\n<p>&#160;</p>\r\n<p>The Armory - Home to CCNMTL's CUMC Office</p>\r\n<p><a class=\"materialCitation asset-image asset-whole\" href=\"/asset/3/annotations/7/\">Left Corner</a></p>\r\n<p>&#160;</p>\r\n<p>Some of our awards. Maurice &amp; Frank</p>\r\n<p><a class=\"materialCitation asset-image asset-whole\" href=\"/asset/2/annotations/5/\">Our esteemed leaders</a></p>", "project_type": "assignment", "author": 2, "title": "Sample Assignment", "modified": "2012-05-26 15:11:25", "date_submitted": "2012-05-26 15:11:25", "course": 1, "participants": [2]}
     },
-    {
-        "pk": 1,
-        "model": "structuredcollaboration.collaborationpolicyrecord",
-        "fields": {
-            "policy_name": "PrivateEditorsAreOwners"
-        }
-    },
-    {
-        "pk": 2,
-        "model": "structuredcollaboration.collaborationpolicyrecord",
-        "fields": {
-            "policy_name": "CourseProtected"
-        }
-    },
     {
         "pk": 2,
         "model": "structuredcollaboration.collaboration",

mediathread/main/fixtures/sample_assignment_and_response.json

@@ -1 +1 @@
-[{"pk": 1, "model": "projects.project", "fields": {"body": "<p>The Columbia Center for New Media Teaching and Learning (CCNMTL) was founded at Columbia University in 1999 to enhance teaching and learning through the purposeful use of new media and technology. In partnership with faculty, the Center supports efforts ranging from basic course website management to advanced project development.&#160;<span class=\"caps\">CCNMTL&#160;</span>is committed to remaining a leader in the field of new media teaching and learning, engaging faculty, educators, librarians, partner institutions, and the community in the reinvention of education for the digital age.</p>\r\n<p>We are committed to ongoing evaluation of the efficacy of our work within the University.</p>\r\n<p>&#160;</p>\r\n<p>The Armory - Home to CCNMTL's CUMC Office</p>\r\n<p><a class=\"materialCitation asset-image asset-whole\" href=\"/asset/3/annotations/7/\">Left Corner</a></p>\r\n<p>&#160;</p>\r\n<p>Some of our awards. Maurice &amp; Frank</p>\r\n<p><a class=\"materialCitation asset-image asset-whole\" href=\"/asset/2/annotations/5/\">Our esteemed leaders</a></p>", "project_type": "assignment", "author": 2, "title": "Sample Assignment", "modified": "2012-05-26 15:11:25", "date_submitted": "2012-05-26 15:11:25", "course": 1, "participants": [2]}}, {"pk": 2, "model": "projects.project", "fields": {"body": "<p>The Columbia Center for New Teaching and Learning was (CCNMTL)</p>\r\n<p>&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; was founded at Columbia University in 1999 to enhance teaching and</p>\r\n<p>&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; learning through the purposeful use of new media and technology</p>", "author": 3, "title": "Sample Assignment Response", "modified": "2012-05-26 15:17:06", "date_submitted": "2012-05-26 15:11:25", "course": 1, "participants": [3]}}, {"pk": 1, "model": "structuredcollaboration.collaborationpolicyrecord", "fields": {"policy_name": "PrivateEditorsAreOwners"}}, {"pk": 2, "model": "structuredcollaboration.collaborationpolicyrecord", "fields": {"policy_name": "CourseProtected"}}, {"pk": 3, "model": "structuredcollaboration.collaborationpolicyrecord", "fields": {"policy_name": "InstructorShared"}}, {"pk": 2, "model": "structuredcollaboration.collaboration", "fields": {"group": null, "context": 1, "title": "Sample Assignment", "policy_record": 2, "object_pk": "1", "_parent": null, "user": 2, "content_type": 21, "slug": null}}, {"pk": 3, "model": "structuredcollaboration.collaboration", "fields": {"group": null, "context": 1, "title": "Sample Assignment Response", "policy_record": 3, "object_pk": "2", "_parent": 2, "user": 3, "content_type": 21, "slug": null}}, {"pk": 1, "model": "structuredcollaboration.collaboration", "fields": {"group": 2, "context": null, "title": "Sample Course", "policy_record": null, "object_pk": "1", "_parent": null, "user": null, "content_type": 8, "slug": "Sample_Course"}}]
+[{"pk": 1, "model": "projects.project", "fields": {"body": "<p>The Columbia Center for New Media Teaching and Learning (CCNMTL) was founded at Columbia University in 1999 to enhance teaching and learning through the purposeful use of new media and technology. In partnership with faculty, the Center supports efforts ranging from basic course website management to advanced project development.&#160;<span class=\"caps\">CCNMTL&#160;</span>is committed to remaining a leader in the field of new media teaching and learning, engaging faculty, educators, librarians, partner institutions, and the community in the reinvention of education for the digital age.</p>\r\n<p>We are committed to ongoing evaluation of the efficacy of our work within the University.</p>\r\n<p>&#160;</p>\r\n<p>The Armory - Home to CCNMTL's CUMC Office</p>\r\n<p><a class=\"materialCitation asset-image asset-whole\" href=\"/asset/3/annotations/7/\">Left Corner</a></p>\r\n<p>&#160;</p>\r\n<p>Some of our awards. Maurice &amp; Frank</p>\r\n<p><a class=\"materialCitation asset-image asset-whole\" href=\"/asset/2/annotations/5/\">Our esteemed leaders</a></p>", "project_type": "assignment", "author": 2, "title": "Sample Assignment", "modified": "2012-05-26 15:11:25", "date_submitted": "2012-05-26 15:11:25", "course": 1, "participants": [2]}}, {"pk": 2, "model": "projects.project", "fields": {"body": "<p>The Columbia Center for New Teaching and Learning was (CCNMTL)</p>\r\n<p>&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; was founded at Columbia University in 1999 to enhance teaching and</p>\r\n<p>&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; learning through the purposeful use of new media and technology</p>", "author": 3, "title": "Sample Assignment Response", "modified": "2012-05-26 15:17:06", "date_submitted": "2012-05-26 15:11:25", "course": 1, "participants": [3]}}, {"pk": 2, "model": "structuredcollaboration.collaboration", "fields": {"group": null, "context": 1, "title": "Sample Assignment", "policy_record": 2, "object_pk": "1", "_parent": null, "user": 2, "content_type": 21, "slug": null}}, {"pk": 3, "model": "structuredcollaboration.collaboration", "fields": {"group": null, "context": 1, "title": "Sample Assignment Response", "policy_record": 3, "object_pk": "2", "_parent": 2, "user": 3, "content_type": 21, "slug": null}}, {"pk": 1, "model": "structuredcollaboration.collaboration", "fields": {"group": 2, "context": null, "title": "Sample Course", "policy_record": null, "object_pk": "1", "_parent": null, "user": null, "content_type": 8, "slug": "Sample_Course"}}]

structuredcollaboration/__init__.py

@@ -1 +0,0 @@
-default_app_config = 'structuredcollaboration.apps.CollaborationPolicyConfig'

structuredcollaboration/migrations/0004_auto_20151016_1401.py

@@ -0,0 +1,56 @@
+# -*- coding: utf-8 -*-
+from __future__ import unicode_literals
+
+from django.db import migrations
+
+
+def get_or_create_policies(apps, schema_editor):
+    CollaborationPolicyRecord = apps.get_model('structuredcollaboration',
+                                               'CollaborationPolicyRecord')
+
+    valid_policies = [
+        'PrivateEditorsAreOwners',
+        'PublicEditorsAreOwners',
+        'PrivateStudentAndFaculty',
+        'CourseProtected',
+        'InstructorShared',
+        'InstructorManaged',
+        'CourseCollaboration'
+    ]
+
+    for p in valid_policies:
+        CollaborationPolicyRecord.objects.get_or_create(policy_name=p)
+
+
+def deprecate_policies(apps, schema_editor):
+    invalid_policies = [
+        'Assignment',
+        'PublicAssignment'
+    ]
+
+    CollaborationPolicyRecord = apps.get_model('structuredcollaboration',
+                                               'CollaborationPolicyRecord')
+    Collaboration = apps.get_model('structuredcollaboration',
+                                   'Collaboration')
+
+    course_protected = CollaborationPolicyRecord.objects.get(
+        policy_name='CourseProtected')
+
+    for p in invalid_policies:
+        policies = Collaboration.objects.filter(policy_record__policy_name=p)
+        policies.update(policy_record=course_protected)
+
+    CollaborationPolicyRecord.objects.filter(
+        policy_name__in=invalid_policies).delete()
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('structuredcollaboration', '0003_auto_20150509_1914'),
+    ]
+
+    operations = [
+        migrations.RunPython(get_or_create_policies),
+        migrations.RunPython(deprecate_policies)
+    ]

structuredcollaboration/models.py

@@ -1,3 +1,5 @@
+import importlib
+
 from django.conf import settings
 from django.contrib.auth.models import User, Group
 from django.contrib.contenttypes import generic
@@ -7,27 +9,7 @@
 from django.utils.translation import ugettext_lazy as _
 
 
-DEFAULT_POLICY = getattr(settings, 'DEFAULT_COLLABORATION_POLICY',
-                         'PublicEditorsAreOwners')
-
-
-class CollaborationPolicyRecordManager(models.Manager):
-    '''
-        @todo - consider pulling this whole registration approach.
-        feels overcomplicated & unnecessary. The primary aim here
-        seems to be caching instances of the policies.
-    '''
-    registered_policies = dict()
-
-    def policy_instance(self, record):
-        return self.registered_policies[record.policy_name]
-
-    def register_policy(self, policy_class, policy_key, policy_title):
-        self.registered_policies[policy_key] = policy_class()
-
-
 class CollaborationPolicyRecord(models.Model):
-    objects = CollaborationPolicyRecordManager()
     policy_name = models.CharField(max_length=512)
 
     def __unicode__(self):
@@ -36,6 +18,17 @@ def __unicode__(self):
     def __eq__(self, other):
         return self.policy_name is other or self is other
 
+    @classmethod
+    def class_for_name(cls, class_name):
+        # load the module, will raise ImportError if module cannot be loaded
+        m = importlib.import_module('structuredcollaboration.policies')
+        # get the class, will raise AttributeError if class cannot be found
+        c = getattr(m, class_name)
+        return c
+
+    def policy_instance(self):
+        return self.class_for_name(self.policy_name)()
+
 
 class CollaborationManager(models.Manager):
     def get_for_object_list(self, object_list):
@@ -142,13 +135,12 @@ def append_child(self, obj=None):
         return coll
 
     def get_policy(self):
-        if self.policy_record:
-            return CollaborationPolicyRecord.objects.policy_instance(
-                self.policy_record)
-        else:
-            record, created = CollaborationPolicyRecord.objects.get_or_create(
-                policy_name=DEFAULT_POLICY)
-            return CollaborationPolicyRecord.objects.policy_instance(record)
+        if not self.policy_record:
+            policy_name = getattr(settings, 'DEFAULT_COLLABORATION_POLICY',
+                                  'PublicEditorsAreOwners')
+            self.set_policy(policy_name)
+            self.save()
+        return self.policy_record.policy_instance()
 
     def set_policy(self, policy_name):
         if policy_name is None: