Fix unicode-related failures in CSV upload.

TNL-586

lms/djangoapps/instructor_task/models.py

@@ -209,6 +209,15 @@ class ReportStore(object):
         elif storage_type.lower() == "localfs":
             return LocalFSReportStore.from_config()
 
+    def _get_utf8_encoded_rows(self, rows):
+        """
+        Given a list of `rows` containing unicode strings, return a
+        new list of rows with those strings encoded as utf-8 for CSV
+        compatibility.
+        """
+        for row in rows:
+            yield [unicode(item).encode('utf-8') for item in row]
+
 
 class S3ReportStore(ReportStore):
     """
@@ -306,7 +315,8 @@ class S3ReportStore(ReportStore):
         """
         output_buffer = StringIO()
         gzip_file = GzipFile(fileobj=output_buffer, mode="wb")
-        csv.writer(gzip_file).writerows(rows)
+        csvwriter = csv.writer(gzip_file)
+        csvwriter.writerows(self._get_utf8_encoded_rows(rows))
         gzip_file.close()
 
         self.store(course_id, filename, output_buffer)
@@ -384,7 +394,9 @@ class LocalFSReportStore(ReportStore):
         write this data out.
         """
         output_buffer = StringIO()
-        csv.writer(output_buffer).writerows(rows)
+        csvwriter = csv.writer(output_buffer)
+        csvwriter.writerows(self._get_utf8_encoded_rows(rows))
+
         self.store(course_id, filename, output_buffer)
 
     def links_for(self, course_id):

lms/djangoapps/instructor_task/tasks_helper.py

@@ -575,7 +575,7 @@ def push_grades_to_s3(_xmodule_instance_args, _entry_id, course_id, _task_input,
             # possible for a student to have a 0.0 show up in their row but
             # still have 100% for the course.
             row_percents = [percents.get(label, 0.0) for label in header]
-            rows.append([student.id, student.email.encode('utf-8'), student.username, gradeset['percent']] + row_percents)
+            rows.append([student.id, student.email, student.username, gradeset['percent']] + row_percents)
         else:
             # An empty gradeset means we failed to grade a student.
             num_failed += 1

lms/djangoapps/instructor_task/tests/test_tasks_helper.py

@@ -33,16 +33,16 @@ class TestReport(ModuleStoreTestCase):
         if os.path.exists(settings.GRADES_DOWNLOAD['ROOT_PATH']):
             shutil.rmtree(settings.GRADES_DOWNLOAD['ROOT_PATH'])
 
+    def create_student(self, username, email):
+        student = UserFactory.create(username=username, email=email)
+        CourseEnrollmentFactory.create(user=student, course_id=self.course.id)
+
 
 @ddt.ddt
 class TestInstructorGradeReport(TestReport):
     """
     Tests that CSV grade report generation works.
     """
-    def create_student(self, username, email):
-        student = UserFactory.create(username=username, email=email)
-        CourseEnrollmentFactory.create(user=student, course_id=self.course.id)
-
     @ddt.data([u'student@example.com', u'ni\xf1o@example.com'])
     def test_unicode_emails(self, emails):
         """
@@ -60,6 +60,7 @@ class TestInstructorGradeReport(TestReport):
         self.assertEquals(result['succeeded'], result['attempted'])
 
 
+@ddt.ddt
 class TestStudentReport(TestReport):
     """
     Tests that CSV student profile report generation works.
@@ -73,3 +74,27 @@ class TestStudentReport(TestReport):
 
         self.assertEquals(len(links), 1)
         self.assertEquals(result, UPDATE_STATUS_SUCCEEDED)
+
+    @ddt.data([u'student', u'student\xec'])
+    def test_unicode_usernames(self, students):
+        """
+        Test that students with unicode characters in their usernames
+        are handled.
+        """
+        for i, student in enumerate(students):
+            self.create_student(username=student, email='student{0}@example.com'.format(i))
+
+        self.current_task = Mock()
+        self.current_task.update_state = Mock()
+        task_input = {
+            'features': [
+                'id', 'username', 'name', 'email', 'language', 'location',
+                'year_of_birth', 'gender', 'level_of_education', 'mailing_address',
+                'goals'
+            ]
+        }
+        with patch('instructor_task.tasks_helper._get_current_task') as mock_current_task:
+            mock_current_task.return_value = self.current_task
+            result = push_students_csv_to_s3(None, None, self.course.id, task_input, 'calculated')
+        #This assertion simply confirms that the generation completed with no errors
+        self.assertEquals(result, UPDATE_STATUS_SUCCEEDED)