Update the student transfer command to transfer to multiple courses.

Quick cleanup

Making kwarg to suppress unenroll events.

pylint and pep8 errors cleaned up.

add commit on success.

Changing transactional behavior of the management command.

common/djangoapps/student/management/commands/transfer_students.py

+"""
+Transfer Student Management Command
+"""
+from django.db import transaction
+from opaque_keys.edx.keys import CourseKey
 from optparse import make_option
-from django.core.management.base import BaseCommand
 from django.contrib.auth.models import User
 from student.models import CourseEnrollment
 from shoppingcart.models import CertificateItem
-from opaque_keys.edx.locations import SlashSeparatedCourseKey
+from track.management.tracked_command import TrackedCommand
 
 
-class Command(BaseCommand):
+class TransferStudentError(Exception):
+    """Generic Error when handling student transfers."""
+    pass
+
+
+class Command(TrackedCommand):
+    """Management Command for transferring students from one course to new courses."""
     help = """
     This command takes two course ids as input and transfers
     all students enrolled in one course into the other.  This will
-    remove them from the first class and enroll them in the second
-    class in the same mode as the first one. eg. honor, verified,
+    remove them from the first class and enroll them in the specified
+    class(es) in the same mode as the first one. eg. honor, verified,
     audit.
 
     example:
         # Transfer students from the old demoX class to a new one.
         manage.py ... transfer_students -f edX/Open_DemoX/edx_demo_course -t edX/Open_DemoX/new_demoX
+
+        # Transfer students from old course to new, with original certificate items.
+        manage.py ... transfer_students -f edX/Open_DemoX/edx_demo_course -t edX/Open_DemoX/new_demoX -c true
+
+        # Transfer students from the old demoX class into two new classes.
+        manage.py ... transfer_students -f edX/Open_DemoX/edx_demo_course
+            -t edX/Open_DemoX/new_demoX,edX/Open_DemoX/edX_Insider
+
     """
 
-    option_list = BaseCommand.option_list + (
+    option_list = TrackedCommand.option_list + (
         make_option('-f', '--from',
                     metavar='SOURCE_COURSE',
                     dest='source_course',
                     help='The course to transfer students from.'),
         make_option('-t', '--to',
-                    metavar='DEST_COURSE',
-                    dest='dest_course',
-                    help='The new course to enroll the student into.'),
+                    metavar='DEST_COURSE_LIST',
+                    dest='dest_course_list',
+                    help='The new course(es) to enroll the student into.'),
+        make_option('-c', '--transfer-certificates',
+                    metavar='TRANSFER_CERTIFICATES',
+                    dest='transfer_certificates',
+                    help="If True, try to transfer certificate items to the new course.")
     )
 
-    def handle(self, *args, **options):
-        source_key = SlashSeparatedCourseKey.from_deprecated_string(options['source_course'])
-        dest_key = SlashSeparatedCourseKey.from_deprecated_string(options['dest_course'])
+    @transaction.commit_manually
+    def handle(self, *args, **options):  # pylint: disable=unused-argument
+        source_key = CourseKey.from_string(options.get('source_course', ''))
+        dest_keys = []
+        for course_key in options.get('dest_course_list', '').split(','):
+            dest_keys.append(CourseKey.from_string(course_key))
+
+        if not source_key or not dest_keys:
+            raise TransferStudentError(u"Must have a source course and destination course specified.")
+
+        tc_option = options.get('transfer_certificates', '')
+        transfer_certificates = ('true' == tc_option.lower()) if tc_option else False
+        if transfer_certificates and len(dest_keys) != 1:
+            raise TransferStudentError(u"Cannot transfer certificate items from one course to many.")
 
         source_students = User.objects.filter(
             courseenrollment__course_id=source_key
         )
 
         for user in source_students:
-            if CourseEnrollment.is_enrolled(user, dest_key):
-                # Un Enroll from source course but don't mess
-                # with the enrollment in the destination course.
-                CourseEnrollment.unenroll(user, source_key)
-                print("Unenrolled {} from {}".format(user.username, source_key.to_deprecated_string()))
-                msg = "Skipping {}, already enrolled in destination course {}"
-                print(msg.format(user.username, dest_key.to_deprecated_string()))
-                continue
-
-            print("Moving {}.".format(user.username))
-            # Find the old enrollment.
-            enrollment = CourseEnrollment.objects.get(
-                user=user,
-                course_id=source_key
+            with transaction.commit_on_success():
+                print("Moving {}.".format(user.username))
+                # Find the old enrollment.
+                enrollment = CourseEnrollment.objects.get(
+                    user=user,
+                    course_id=source_key
+                )
+
+                # Move the Student between the classes.
+                mode = enrollment.mode
+                old_is_active = enrollment.is_active
+                CourseEnrollment.unenroll(user, source_key, emit_unenrollment_event=False)
+                print(u"Unenrolled {} from {}".format(user.username, unicode(source_key)))
+
+                for dest_key in dest_keys:
+                    if CourseEnrollment.is_enrolled(user, dest_key):
+                        # Un Enroll from source course but don't mess
+                        # with the enrollment in the destination course.
+                        msg = u"Skipping {}, already enrolled in destination course {}"
+                        print(msg.format(user.username, unicode(dest_key)))
+                    else:
+                        new_enrollment = CourseEnrollment.enroll(user, dest_key, mode=mode)
+
+                        # Un-enroll from the new course if the user had un-enrolled
+                        # form the old course.
+                        if not old_is_active:
+                            new_enrollment.update_enrollment(is_active=False, emit_unenrollment_event=False)
+
+                        if transfer_certificates:
+                            self._transfer_certificate_item(source_key, enrollment, user, dest_keys, new_enrollment)
+
+    @staticmethod
+    def _transfer_certificate_item(source_key, enrollment, user, dest_keys, new_enrollment):
+        """ Transfer the certificate item from one course to another.
+
+        Do not use this generally, since certificate items are directly associated with a particular purchase.
+        This should only be used when a single course to a new location. This cannot be used when transferring
+        from one course to many.
+
+        Args:
+            source_key (str): The course key string representation for the original course.
+            enrollment (CourseEnrollment): The original enrollment to move the certificate item from.
+            user (User): The user to transfer the item for.
+            dest_keys (list): A list of course key strings to transfer the item to.
+            new_enrollment (CourseEnrollment): The new enrollment to associate the certificate item with.
+
+        Returns:
+            None
+
+        """
+        try:
+            certificate_item = CertificateItem.objects.get(
+                course_id=source_key,
+                course_enrollment=enrollment
             )
+        except CertificateItem.DoesNotExist:
+            print(u"No certificate for {}".format(user))
+            return
 
-            # Move the Student between the classes.
-            mode = enrollment.mode
-            old_is_active = enrollment.is_active
-            CourseEnrollment.unenroll(user, source_key)
-            new_enrollment = CourseEnrollment.enroll(user, dest_key, mode=mode)
-
-            # Unenroll from the new coures if the user had unenrolled
-            # form the old course.
-            if not old_is_active:
-                new_enrollment.update_enrollment(is_active=False)
-
-            if mode == 'verified':
-                try:
-                    certificate_item = CertificateItem.objects.get(
-                        course_id=source_key,
-                        course_enrollment=enrollment
-                    )
-                except CertificateItem.DoesNotExist:
-                    print("No certificate for {}".format(user))
-                    continue
-
-                certificate_item.course_id = dest_key
-                certificate_item.course_enrollment = new_enrollment
-                certificate_item.save()
+        certificate_item.course_id = dest_keys[0]
+        certificate_item.course_enrollment = new_enrollment

common/djangoapps/student/management/tests/__init__.py

+"""Tests for Student Management Commands."""

common/djangoapps/student/management/tests/test_transfer_students.py

+"""
+Tests the transfer student management command
+"""
+from django.conf import settings
+from opaque_keys.edx import locator
+import unittest
+import ddt
+from student.management.commands import transfer_students
+from student.models import CourseEnrollment
+from student.tests.factories import UserFactory
+from xmodule.modulestore.tests.django_utils import ModuleStoreTestCase
+from xmodule.modulestore.tests.factories import CourseFactory
+
+
+@unittest.skipUnless(settings.ROOT_URLCONF == 'lms.urls', 'Test only valid in lms')
+@ddt.ddt
+class TestTransferStudents(ModuleStoreTestCase):
+    """Tests for transferring students between courses."""
+
+    PASSWORD = 'test'
+
+    def test_transfer_students(self):
+        student = UserFactory()
+        student.set_password(self.PASSWORD)  # pylint: disable=E1101
+        student.save()   # pylint: disable=E1101
+
+        # Original Course
+        original_course_location = locator.CourseLocator('Org0', 'Course0', 'Run0')
+        course = self._create_course(original_course_location)
+        # Enroll the student in 'verified'
+        CourseEnrollment.enroll(student, course.id, mode="verified")
+
+        # New Course 1
+        course_location_one = locator.CourseLocator('Org1', 'Course1', 'Run1')
+        new_course_one = self._create_course(course_location_one)
+
+        # New Course 2
+        course_location_two = locator.CourseLocator('Org2', 'Course2', 'Run2')
+        new_course_two = self._create_course(course_location_two)
+        original_key = unicode(course.id)
+        new_key_one = unicode(new_course_one.id)
+        new_key_two = unicode(new_course_two.id)
+
+        # Run the actual management command
+        transfer_students.Command().handle(
+            source_course=original_key, dest_course_list=new_key_one + "," + new_key_two
+        )
+
+        # Confirm the enrollment mode is verified on the new courses, and enrollment is enabled as appropriate.
+        self.assertEquals(('verified', False), CourseEnrollment.enrollment_mode_for_user(student, course.id))
+        self.assertEquals(('verified', True), CourseEnrollment.enrollment_mode_for_user(student, new_course_one.id))
+        self.assertEquals(('verified', True), CourseEnrollment.enrollment_mode_for_user(student, new_course_two.id))
+
+    def _create_course(self, course_location):
+        """ Creates a course """
+        return CourseFactory.create(
+            org=course_location.org,
+            number=course_location.course,
+            run=course_location.run
+        )

common/djangoapps/student/models.py

@@ -776,7 +776,7 @@ class CourseEnrollment(models.Model):
             is_course_full = cls.num_enrolled_in(course.id) >= course.max_student_enrollments_allowed
         return is_course_full
 
-    def update_enrollment(self, mode=None, is_active=None):
+    def update_enrollment(self, mode=None, is_active=None, emit_unenrollment_event=True):
         """
         Updates an enrollment for a user in a class.  This includes options
         like changing the mode, toggling is_active True/False, etc.
@@ -784,6 +784,7 @@ class CourseEnrollment(models.Model):
         Also emits relevant events for analytics purposes.
 
         This saves immediately.
+
         """
         activation_changed = False
         # if is_active is None, then the call to update_enrollment didn't specify
@@ -813,7 +814,7 @@ class CourseEnrollment(models.Model):
                           u"mode:{}".format(self.mode)]
                 )
 
-            else:
+            elif emit_unenrollment_event:
                 UNENROLL_DONE.send(sender=None, course_enrollment=self)
 
                 self.emit_event(EVENT_NAME_ENROLLMENT_DEACTIVATED)
@@ -987,7 +988,7 @@ class CourseEnrollment(models.Model):
             raise
 
     @classmethod
-    def unenroll(cls, user, course_id):
+    def unenroll(cls, user, course_id, emit_unenrollment_event=True):
         """
         Remove the user from a given course. If the relevant `CourseEnrollment`
         object doesn't exist, we log an error but don't throw an exception.
@@ -997,10 +998,12 @@ class CourseEnrollment(models.Model):
                adding an enrollment for it.
 
         `course_id` is our usual course_id string (e.g. "edX/Test101/2013_Fall)
+
+        `emit_unenrollment_events` can be set to False to suppress events firing.
         """
         try:
             record = CourseEnrollment.objects.get(user=user, course_id=course_id)
-            record.update_enrollment(is_active=False)
+            record.update_enrollment(is_active=False, emit_unenrollment_event=emit_unenrollment_event)
 
         except cls.DoesNotExist:
             err_msg = u"Tried to unenroll student {} from {} but they were not enrolled"