Force unique course_id for bulk email authorization

LMS-2134

lms/djangoapps/bulk_email/migrations/0009_force_unique_course_ids.py

+# -*- coding: utf-8 -*-
+import datetime
+from south.db import db
+from south.v2 import SchemaMigration
+from django.db import models
+
+
+class Migration(SchemaMigration):
+
+    def forwards(self, orm):
+        # Adding unique constraint on 'CourseAuthorization', fields ['course_id']
+        db.create_unique('bulk_email_courseauthorization', ['course_id'])
+
+
+    def backwards(self, orm):
+        # Removing unique constraint on 'CourseAuthorization', fields ['course_id']
+        db.delete_unique('bulk_email_courseauthorization', ['course_id'])
+
+
+    models = {
+        'auth.group': {
+            'Meta': {'object_name': 'Group'},
+            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
+            'name': ('django.db.models.fields.CharField', [], {'unique': 'True', 'max_length': '80'}),
+            'permissions': ('django.db.models.fields.related.ManyToManyField', [], {'to': "orm['auth.Permission']", 'symmetrical': 'False', 'blank': 'True'})
+        },
+        'auth.permission': {
+            'Meta': {'ordering': "('content_type__app_label', 'content_type__model', 'codename')", 'unique_together': "(('content_type', 'codename'),)", 'object_name': 'Permission'},
+            'codename': ('django.db.models.fields.CharField', [], {'max_length': '100'}),
+            'content_type': ('django.db.models.fields.related.ForeignKey', [], {'to': "orm['contenttypes.ContentType']"}),
+            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
+            'name': ('django.db.models.fields.CharField', [], {'max_length': '50'})
+        },
+        'auth.user': {
+            'Meta': {'object_name': 'User'},
+            'date_joined': ('django.db.models.fields.DateTimeField', [], {'default': 'datetime.datetime.now'}),
+            'email': ('django.db.models.fields.EmailField', [], {'max_length': '75', 'blank': 'True'}),
+            'first_name': ('django.db.models.fields.CharField', [], {'max_length': '30', 'blank': 'True'}),
+            'groups': ('django.db.models.fields.related.ManyToManyField', [], {'to': "orm['auth.Group']", 'symmetrical': 'False', 'blank': 'True'}),
+            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
+            'is_active': ('django.db.models.fields.BooleanField', [], {'default': 'True'}),
+            'is_staff': ('django.db.models.fields.BooleanField', [], {'default': 'False'}),
+            'is_superuser': ('django.db.models.fields.BooleanField', [], {'default': 'False'}),
+            'last_login': ('django.db.models.fields.DateTimeField', [], {'default': 'datetime.datetime.now'}),
+            'last_name': ('django.db.models.fields.CharField', [], {'max_length': '30', 'blank': 'True'}),
+            'password': ('django.db.models.fields.CharField', [], {'max_length': '128'}),
+            'user_permissions': ('django.db.models.fields.related.ManyToManyField', [], {'to': "orm['auth.Permission']", 'symmetrical': 'False', 'blank': 'True'}),
+            'username': ('django.db.models.fields.CharField', [], {'unique': 'True', 'max_length': '30'})
+        },
+        'bulk_email.courseauthorization': {
+            'Meta': {'object_name': 'CourseAuthorization'},
+            'course_id': ('django.db.models.fields.CharField', [], {'unique': 'True', 'max_length': '255', 'db_index': 'True'}),
+            'email_enabled': ('django.db.models.fields.BooleanField', [], {'default': 'False'}),
+            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'})
+        },
+        'bulk_email.courseemail': {
+            'Meta': {'object_name': 'CourseEmail'},
+            'course_id': ('django.db.models.fields.CharField', [], {'max_length': '255', 'db_index': 'True'}),
+            'created': ('django.db.models.fields.DateTimeField', [], {'auto_now_add': 'True', 'blank': 'True'}),
+            'html_message': ('django.db.models.fields.TextField', [], {'null': 'True', 'blank': 'True'}),
+            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
+            'modified': ('django.db.models.fields.DateTimeField', [], {'auto_now': 'True', 'blank': 'True'}),
+            'sender': ('django.db.models.fields.related.ForeignKey', [], {'default': '1', 'to': "orm['auth.User']", 'null': 'True', 'blank': 'True'}),
+            'slug': ('django.db.models.fields.CharField', [], {'max_length': '128', 'db_index': 'True'}),
+            'subject': ('django.db.models.fields.CharField', [], {'max_length': '128', 'blank': 'True'}),
+            'text_message': ('django.db.models.fields.TextField', [], {'null': 'True', 'blank': 'True'}),
+            'to_option': ('django.db.models.fields.CharField', [], {'default': "'myself'", 'max_length': '64'})
+        },
+        'bulk_email.courseemailtemplate': {
+            'Meta': {'object_name': 'CourseEmailTemplate'},
+            'html_template': ('django.db.models.fields.TextField', [], {'null': 'True', 'blank': 'True'}),
+            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
+            'plain_template': ('django.db.models.fields.TextField', [], {'null': 'True', 'blank': 'True'})
+        },
+        'bulk_email.optout': {
+            'Meta': {'unique_together': "(('user', 'course_id'),)", 'object_name': 'Optout'},
+            'course_id': ('django.db.models.fields.CharField', [], {'max_length': '255', 'db_index': 'True'}),
+            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
+            'user': ('django.db.models.fields.related.ForeignKey', [], {'to': "orm['auth.User']", 'null': 'True'})
+        },
+        'contenttypes.contenttype': {
+            'Meta': {'ordering': "('name',)", 'unique_together': "(('app_label', 'model'),)", 'object_name': 'ContentType', 'db_table': "'django_content_type'"},
+            'app_label': ('django.db.models.fields.CharField', [], {'max_length': '100'}),
+            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
+            'model': ('django.db.models.fields.CharField', [], {'max_length': '100'}),
+            'name': ('django.db.models.fields.CharField', [], {'max_length': '100'})
+        }
+    }
+
+    complete_apps = ['bulk_email']
\ No newline at end of file

lms/djangoapps/bulk_email/models.py

@@ -219,7 +219,7 @@ class CourseAuthorization(models.Model):
     Enable the course email feature on a course-by-course basis.
     """
     # The course that these features are attached to.
-    course_id = models.CharField(max_length=255, db_index=True)
+    course_id = models.CharField(max_length=255, db_index=True, unique=True)
 
     # Whether or not to enable instructor email
     email_enabled = models.BooleanField(default=False)

lms/djangoapps/bulk_email/tests/test_forms.py

@@ -46,6 +46,34 @@ class CourseAuthorizationFormTest(ModuleStoreTestCase):
         self.assertTrue(CourseAuthorization.instructor_email_enabled(self.course.id))
 
     @patch.dict(settings.FEATURES, {'ENABLE_INSTRUCTOR_EMAIL': True, 'REQUIRE_COURSE_EMAIL_AUTH': True})
+    def test_repeat_course(self):
+        # Initially course shouldn't be authorized
+        self.assertFalse(CourseAuthorization.instructor_email_enabled(self.course.id))
+        # Test authorizing the course, which should totally work
+        form_data = {'course_id': self.course.id, 'email_enabled': True}
+        form = CourseAuthorizationAdminForm(data=form_data)
+        # Validation should work
+        self.assertTrue(form.is_valid())
+        form.save()
+        # Check that this course is authorized
+        self.assertTrue(CourseAuthorization.instructor_email_enabled(self.course.id))
+
+        # Now make a new course authorization with the same course id that tries to turn email off
+        form_data = {'course_id': self.course.id, 'email_enabled': False}
+        form = CourseAuthorizationAdminForm(data=form_data)
+        # Validation should not work because course_id field is unique
+        self.assertFalse(form.is_valid())
+        self.assertEquals(
+            "Course authorization with this Course id already exists.",
+            form._errors['course_id'][0]  # pylint: disable=protected-access
+        )
+        with self.assertRaisesRegexp(ValueError, "The CourseAuthorization could not be created because the data didn't validate."):
+            form.save()
+
+        # Course should still be authorized (invalid attempt had no effect)
+        self.assertTrue(CourseAuthorization.instructor_email_enabled(self.course.id))
+
+    @patch.dict(settings.FEATURES, {'ENABLE_INSTRUCTOR_EMAIL': True, 'REQUIRE_COURSE_EMAIL_AUTH': True})
     def test_form_typo(self):
         # Munge course id
         bad_id = self.course.id + '_typo'