Add system_wide_roles app and roles classes (#20935)

* New system_wide_roles app added in openedx/core/djangoapps
* Added SystemWideRole and SystemWideRoleAssignment classes to govern
  non-enterprise system wide roles

PROD-424

cms/envs/common.py

@@ -1128,6 +1128,9 @@ INSTALLED_APPS = [
     'lms.djangoapps.verify_student.apps.VerifyStudentConfig',
     'completion',
 
+    # System Wide Roles
+    'openedx.core.djangoapps.system_wide_roles',
+
     # Microsite configuration application
     'microsite_configuration',
 

lms/envs/common.py

@@ -2321,6 +2321,9 @@ INSTALLED_APPS = [
     # defined by oauth_provider.  If those tables don't exist, an error can occur.
     'oauth_provider',
 
+    # System Wide Roles
+    'openedx.core.djangoapps.system_wide_roles',
+
     'openedx.core.djangoapps.auth_exchange',
 
     # For the wiki

openedx/core/djangoapps/system_wide_roles/migrations/0001_SystemWideRole_SystemWideRoleAssignment.py

@@ -0,0 +1,47 @@
+# -*- coding: utf-8 -*-
+# Generated by Django 1.11.22 on 2019-07-02 09:33
+from __future__ import unicode_literals
+
+from django.conf import settings
+from django.db import migrations, models
+import django.db.models.deletion
+import django.utils.timezone
+import model_utils.fields
+
+
+class Migration(migrations.Migration):
+
+    initial = True
+
+    dependencies = [
+        migrations.swappable_dependency(settings.AUTH_USER_MODEL),
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name='SystemWideRole',
+            fields=[
+                ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('created', model_utils.fields.AutoCreatedField(default=django.utils.timezone.now, editable=False, verbose_name='created')),
+                ('modified', model_utils.fields.AutoLastModifiedField(default=django.utils.timezone.now, editable=False, verbose_name='modified')),
+                ('name', models.CharField(db_index=True, max_length=255, unique=True)),
+                ('description', models.TextField(blank=True, null=True)),
+            ],
+            options={
+                'abstract': False,
+            },
+        ),
+        migrations.CreateModel(
+            name='SystemWideRoleAssignment',
+            fields=[
+                ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('created', model_utils.fields.AutoCreatedField(default=django.utils.timezone.now, editable=False, verbose_name='created')),
+                ('modified', model_utils.fields.AutoLastModifiedField(default=django.utils.timezone.now, editable=False, verbose_name='modified')),
+                ('role', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, to='system_wide_roles.SystemWideRole')),
+                ('user', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, to=settings.AUTH_USER_MODEL)),
+            ],
+            options={
+                'abstract': False,
+            },
+        ),
+    ]

openedx/core/djangoapps/system_wide_roles/models.py

@@ -0,0 +1,51 @@
+"""
+Django models for system wide roles.
+"""
+from __future__ import unicode_literals
+
+from edx_rbac.models import UserRole, UserRoleAssignment
+
+
+class SystemWideRole(UserRole):  # pylint: disable=model-missing-unicode
+    """
+    User role definitions to govern non-enterprise system wide roles.
+     .. no_pii:
+    """
+
+    def __str__(self):
+        """
+        Return human-readable string representation.
+        """
+        str_representation = "<SystemWideRole {role}>"
+        return str_representation.format(role=self.name)
+
+    def __repr__(self):
+        """
+        Return uniquely identifying string representation.
+        """
+        return self.__str__()
+
+
+class SystemWideRoleAssignment(UserRoleAssignment):  # pylint: disable=model-missing-unicode
+    """
+    Model to map users to a SystemWideRole.
+     .. no_pii:
+    """
+
+    role_class = SystemWideRole
+
+    def __str__(self):
+        """
+        Return human-readable string representation.
+        """
+        str_representation = "<SystemWideRoleAssignment for User {user} assigned to role {role}>"
+        return str_representation.format(
+            user=self.user.id,
+            role=self.role.name
+        )
+
+    def __repr__(self):
+        """
+        Return uniquely identifying string representation.
+        """
+        return self.__str__()

openedx/core/djangoapps/system_wide_roles/tests/test_models.py

@@ -0,0 +1,50 @@
+"""
+Tests for system wide roles' django models.
+"""
+from __future__ import unicode_literals
+
+from django.test import TestCase
+from student.tests.factories import UserFactory
+
+from openedx.core.djangoapps.system_wide_roles.models import SystemWideRole, SystemWideRoleAssignment
+
+
+class SystemWideRoleTests(TestCase):
+    """ Tests for SystemWideRole in system_wide_roles app """
+
+    def setUp(self):
+        super(SystemWideRoleTests, self).setUp()
+        self.role = SystemWideRole.objects.create(name='TestRole')
+
+    def test_str(self):
+        self.assertEqual(str(self.role), '<SystemWideRole TestRole>')
+
+    def test_repr(self):
+        self.assertEqual(repr(self.role), '<SystemWideRole TestRole>')
+
+
+class SystemWideRoleAssignmentTests(TestCase):
+    """ Tests for SystemWideRoleAssignment in system_wide_roles app """
+
+    def setUp(self):
+        super(SystemWideRoleAssignmentTests, self).setUp()
+        self.user = UserFactory.create()
+        self.role = SystemWideRole.objects.create(name='TestRole')
+
+    def test_str(self):
+        role_assignment = SystemWideRoleAssignment.objects.create(role=self.role, user=self.user)
+        self.assertEqual(
+            str(role_assignment),
+            '<SystemWideRoleAssignment for User {user} assigned to role {role}>'.format(
+                user=self.user.id, role=self.role.name
+            )
+        )
+
+    def test_repr(self):
+        role_assignment = SystemWideRoleAssignment.objects.create(role=self.role, user=self.user)
+        self.assertEqual(
+            repr(role_assignment),
+            '<SystemWideRoleAssignment for User {user} assigned to role {role}>'.format(
+                user=self.user.id, role=self.role.name
+            )
+        )