Merge pull request #1253 from django-helpdesk/fix_error_when_no_email_body

Fix error when email has attachment mime part and content mime part missing or empty

helpdesk/email.py

@@ -850,6 +850,9 @@ def extract_email_message_content(
            replies must be extracted
     """
     message_part: MIMEPart = part.get_body()
+    # handle the case where there is no content, just an attachment
+    if not message_part:
+        return None, None
     parent_part: MIMEPart = part
     content_type = message_part.get_content_type()
     # Handle the possibility of a related part formatted email
@@ -902,7 +905,9 @@ def extract_email_message_content(
         # Is either text/plain or some random content-type so just decode the part content and store as is
         mime_content = mime_content_to_string(message_part)
     # We should now have the mime content
-    filtered_body = parse_email_content(mime_content, include_chained_msgs)
+    filtered_body = (
+        parse_email_content(mime_content, include_chained_msgs) if mime_content else ""
+    )
     if not filtered_body or "" == filtered_body.strip():
         # A unit test that has a different HTML content to plain text which seems an invalid case as email
         # tools should retain the HTML to be consistent with the plain text but manage this as a special case
@@ -1088,7 +1093,8 @@ def extract_email_metadata(
         counter, content_parts_excluded = extract_attachments(
             message_obj, files, logger
         )
-        if not content_parts_excluded:
+        # Check if there is expected to be a content part
+        if not content_parts_excluded and (filtered_body or full_body):
             # Unexpected situation and may mean there is a hole in the email processing logic
             logger.warning(
                 "Failed to exclude email content when parsing all MIME parts in the multipart.\

helpdesk/tests/test_get_email.py

@@ -514,6 +514,45 @@ class GetEmailCommonTests(TestCase):
         )
         self.assertIsNone(ticket, f"Ticket was created when it should not be: {ticket}")
 
+    def test_with_attachment_but_no_body_part(self):
+        """
+        Test an email that has no body content but does have an attachment
+        """
+        message, _, _ = utils.generate_multipart_email(
+            type_list=["image"],
+        )
+        # Now send the part to the email workflow
+        extract_email_metadata(message.as_string(), self.queue_public, self.logger)
+        self.assertEqual(len(mail.outbox), 1)  # @UndefinedVariable
+        ticket = Ticket.objects.get()
+        followup = ticket.followup_set.get()
+        # Check  attachment is stored as attached file
+        email_attachment_found = followup.followupattachment_set.exists()
+        self.assertTrue(
+            email_attachment_found,
+            "Email attachment file not found in ticket attachment for empty body.",
+        )
+
+    def test_with_attachment_but_empty_body(self):
+        """
+        Test an email that has an empty body but does have an attachment
+        """
+        message, _, _ = utils.generate_multipart_email(
+            type_list=["plain", "image"],
+            body="",
+        )
+        # Now send the part to the email workflow
+        extract_email_metadata(message.as_string(), self.queue_public, self.logger)
+        self.assertEqual(len(mail.outbox), 1)  # @UndefinedVariable
+        ticket = Ticket.objects.get()
+        followup = ticket.followup_set.get()
+        # Check  attachment is stored as attached file
+        email_attachment_found = followup.followupattachment_set.exists()
+        self.assertTrue(
+            email_attachment_found,
+            "Email attachment file not found in ticket attachment for empty body.",
+        )
+
 
 class EmailTaskTests(TestCase):
     def setUp(self):

helpdesk/tests/utils.py

@@ -288,15 +288,18 @@ def add_simple_email_headers(
 def generate_mime_part(
     locale: str = "en_US",
     part_type: str = "plain",
+    body: str = None,
 ) -> typing.Optional[Message]:
     """
-    Generates amime part of the sepecified type
+    Generates a mime part of the specified type
 
     :param locale: change this to generate locale specific strings
     :param text_type: options are plain, html, image (attachment), file (attachment)
+    :param body: if provided then will be added to the plain mime part only
     """
     if "plain" == part_type:
-        body = get_fake("text", locale=locale, min_length=1024)
+        if body is None:
+            body = get_fake("text", locale=locale, min_length=1024)
         msg = MIMEText(body, part_type)
     elif "html" == part_type:
         body = get_fake_html(locale=locale, wrap_in_body_tag=True)
@@ -317,6 +320,7 @@ def generate_multipart_email(
     type_list: typing.List[str] = ["plain", "html", "image"],
     sub_type: str = None,
     use_short_email: bool = False,
+    body: str = None,
 ) -> typing.Tuple[Message, typing.Tuple[str, str], typing.Tuple[str, str]]:
     """
     Generates an email including headers with the defined multiparts
@@ -325,10 +329,11 @@ def generate_multipart_email(
     :param type_list: options are plain, html, image (attachment), file (attachment), and executable (.exe attachment)
     :param sub_type: multipart sub type that defaults to "mixed" if not specified
     :param use_short_email: produces a "To" or "From" that is only the email address if True
+    :param body: if provided then will be added to the plain mime part only
     """
     msg = MIMEMultipart(sub_type) if sub_type else MIMEMultipart()
     for part_type in type_list:
-        msg.attach(generate_mime_part(locale=locale, part_type=part_type))
+        msg.attach(generate_mime_part(locale=locale, part_type=part_type, body=body))
     from_meta, to_meta = add_simple_email_headers(
         msg, locale=locale, use_short_email=use_short_email
     )
@@ -336,12 +341,15 @@ def generate_multipart_email(
 
 
 def generate_text_email(
-    locale: str = "en_US", use_short_email: bool = False
+    locale: str = "en_US",
+    use_short_email: bool = False,
+    body: str = None,
 ) -> typing.Tuple[Message, typing.Tuple[str, str], typing.Tuple[str, str]]:
     """
     Generates an email including headers
     """
-    body = get_fake("text", locale=locale, min_length=1024)
+    if body is None:
+        body = get_fake("text", locale=locale, min_length=1024)
     msg = MIMEText(body)
     from_meta, to_meta = add_simple_email_headers(
         msg, locale=locale, use_short_email=use_short_email