Refactor html->plaintext conversion (for bulk email) into separate library

common/lib/html_to_text.py

+"""Provides a function to convert html to plaintext."""
+from subprocess import Popen, PIPE
+
+def html_to_text(html_message):
+    """
+    Converts an html message to plaintext.
+    Currently uses lynx in a subprocess; should be refactored to
+    use something more pythonic.
+    """
+    process = Popen(
+        ['lynx', '-stdin', '-display_charset=UTF-8', '-assume_charset=UTF-8', '-dump'],
+        stdin=PIPE,
+        stdout=PIPE
+    )
+    # use lynx to get plaintext
+    (plaintext, err_from_stderr) = process.communicate(
+        input=html_message.encode('utf-8')
+    )
+
+    if err_from_stderr:
+        log.info(err_from_stderr)
+
+    return plaintext

lms/djangoapps/bulk_email/models.py

@@ -14,6 +14,7 @@ class Email(models.Model):
     hash = models.CharField(max_length=128, db_index=True)
     subject = models.CharField(max_length=128, blank=True)
     html_message = models.TextField(null=True, blank=True)
+    text_message = models.TextField(null=True, blank=True)
     created = models.DateTimeField(auto_now_add=True)
     modified = models.DateTimeField(auto_now=True)
 

lms/djangoapps/bulk_email/tasks.py

@@ -8,7 +8,6 @@ import re
 import time
 
 from smtplib import SMTPServerDisconnected, SMTPDataError, SMTPConnectError
-from subprocess import Popen, PIPE
 
 from django.conf import settings
 from django.contrib.auth.models import User, Group
@@ -98,15 +97,9 @@ def course_email(hash_for_msg, to_list, course_title, course_url, throttle=False
 
     subject = "[" + course_title + "] " + msg.subject
 
-    process = Popen(['lynx', '-stdin', '-display_charset=UTF-8', '-assume_charset=UTF-8', '-dump'], stdin=PIPE, stdout=PIPE)
-    (plaintext, err_from_stderr) = process.communicate(input=msg.html_message.encode('utf-8'))  # use lynx to get plaintext
-
     course_title_no_quotes = re.sub(r'"', '', course_title)
     from_addr = '"{0}" Course Staff <{1}>'.format(course_title_no_quotes, settings.DEFAULT_BULK_FROM_EMAIL)
 
-    if err_from_stderr:
-        log.info(err_from_stderr)
-
     try:
         connection = get_connection()
         connection.open()
@@ -136,14 +129,15 @@ def course_email(hash_for_msg, to_list, course_title, course_url, throttle=False
 
             email_msg = EmailMultiAlternatives(
                 subject,
-                plaintext + plain_footer.encode('utf-8'),
+                msg.text_message + plain_footer.encode('utf-8'),
                 from_addr,
                 [email],
                 connection=connection
             )
             email_msg.attach_alternative(msg.html_message + html_footer.encode('utf-8'), 'text/html')
 
-            if throttle or current_task.request.retries > 0:  # throttle if we tried a few times and got the rate limiter
+            # Throttle if we tried a few times and got the rate limiter
+            if throttle or current_task.request.retries > 0:
                 time.sleep(0.2)
 
             try:

lms/djangoapps/bulk_email/tests/test_course_optout.py

@@ -31,6 +31,12 @@ class TestOptoutCourseEmails(ModuleStoreTestCase):
 
         self.client.login(username=self.student.username, password="test")
 
+    def tearDown(self):
+        """
+        Undo all patches.
+        """
+        patch.stopall()
+
     def navigate_to_email_view(self):
         """Navigate to the instructor dash's email view"""
         # Pull up email view on instructor dashboard
@@ -54,6 +60,8 @@ class TestOptoutCourseEmails(ModuleStoreTestCase):
         Make sure student does not receive course email after opting out.
         """
         url = reverse('change_email_settings')
+        # This is a checkbox, so on the post of opting out (that is, an Un-check of the box),
+        # the Post that is sent will not contain 'receive_emails'
         response = self.client.post(url, {'course_id': self.course.id})
         self.assertEquals(json.loads(response.content), {'success': True})
 

lms/djangoapps/bulk_email/tests/test_email.py

@@ -64,6 +64,12 @@ class TestEmailSendFromDashboard(ModuleStoreTestCase):
         selected_email_link = '<a href="#" onclick="goto(\'Email\')" class="selectedmode">Email</a>'
         self.assertTrue(selected_email_link in response.content)
 
+    def tearDown(self):
+        """
+        Undo all patches.
+        """
+        patch.stopall()
+
     def test_send_to_self(self):
         """
         Make sure email send to myself goes to myself.
@@ -185,7 +191,7 @@ class TestEmailSendFromDashboard(ModuleStoreTestCase):
 
         self.assertIn(
             u'ẗëṡẗ ṁëṡṡäġë ḟöṛ äḷḷ ｲ乇丂ｲ ﾶ乇丂丂ﾑg乇 ｷo尺 ﾑﾚﾚ тэѕт мэѕѕаБэ fоѓ аll',
-            mail.outbox[0].body.decode('utf-8')
+            mail.outbox[0].body
         )
 
     def test_unicode_students_send_to_all(self):

lms/djangoapps/bulk_email/tests/test_err_handling.py

@@ -40,8 +40,10 @@ class TestEmailErrors(ModuleStoreTestCase):
 
         self.url = reverse('instructor_dashboard', kwargs={'course_id': self.course.id})
 
+
     def tearDown(self):
         self.smtp_server_thread.stop()
+        patch.stopall()
 
     @patch('bulk_email.tasks.course_email.retry')
     def test_data_err_retry(self, retry):

lms/djangoapps/bulk_email/tests/tests.py

@@ -32,6 +32,12 @@ class TestInstructorDashboardEmailView(ModuleStoreTestCase):
         # URL for email view
         self.email_link = '<a href="#" onclick="goto(\'Email\')" class="None">Email</a>'
 
+    def tearDown(self):
+        """
+        Undo all patches.
+        """
+        patch.stopall()
+
     @patch.dict(settings.MITX_FEATURES, {'ENABLE_INSTRUCTOR_EMAIL': True})
     def test_email_flag_true(self):
         # Assert that the URL for the email view is in the response

lms/djangoapps/instructor/views/legacy.py

@@ -55,6 +55,7 @@ from mitxmako.shortcuts import render_to_string
 
 
 from bulk_email.models import CourseEmail
+from html_to_text import html_to_text
 import datetime
 from hashlib import md5
 from bulk_email import tasks
@@ -706,12 +707,14 @@ def instructor_dashboard(request, course_id):
         to_option = request.POST.get("to_option")
         subject = request.POST.get("subject")
         html_message = request.POST.get("message")
+        text_message = html_to_text(html_message)
 
         email = CourseEmail(course_id=course_id,
                             sender=request.user,
                             to=to_option,
                             subject=subject,
                             html_message=html_message,
+                            text_message=text_message,
                             hash=md5((html_message + subject + datetime.datetime.isoformat(datetime.datetime.now())).encode('utf-8')).hexdigest())
         email.save()