[FIX] mail: add support for Text/RFC822-Headers content-type

WHY:

Some mail servers may provide `Message-Id` header in a section typed
`text/rfc822-headers` instead of a `message/rfc822`

According to https://tools.ietf.org/html/rfc6522#section-4 that section's body
actually contains the headers from the bounced email.

STEPS: a way to reproduce it should be using postfix v2.5+ with setting
bounce_size_limit=1. See
https://github.com/odoo/odoo/pull/42340#issuecomment-617605521

BEFORE: `bounced_message_id` is empty and thus the little email envelope icon
doesn't turn red, nor do the email resend features trigger in the UI. You could
be sending an invoice and never knowing it was bounced.

AFTER: bounces from mail servers that return the `text/rfc822-headers` part will
be handled properly.

---

@Tecnativa TT21170
opw-2162067
opw-2344252
closes #42340
closes #62551

closes odoo/odoo#62706

X-original-commit: 3dc72b357c9bfa81867972c5c9b20dc028932d8b
Signed-off-by: Ivan Yelizariev // IEL <yelizariev@users.noreply.github.com>

3 files changed, 78 insertions, 2 deletions

diff --git a/addons/mail/models/mail_thread.py b/addons/mail/models/mail_thread.py
index 18962e5b049..c0dd08b9b64 100644
--- a/addons/mail/models/mail_thread.py
+++ b/addons/mail/models/mail_thread.py
@@ -19,6 +19,7 @@ import threading
 
 from collections import namedtuple
 from email.message import EmailMessage
+from email import message_from_string, policy
 from lxml import etree
 from werkzeug import urls
 from xmlrpc import client as xmlrpclib
@@ -1327,7 +1328,7 @@ class MailThread(models.AbstractModel):
         if not isinstance(email_message, EmailMessage):
             raise TypeError('message must be an email.message.EmailMessage at this point')
 
-        email_part = next((part for part in email_message.walk() if part.get_content_type() == 'message/rfc822'), None)
+        email_part = next((part for part in email_message.walk() if part.get_content_type() in {'message/rfc822', 'text/rfc822-headers'}), None)
         dsn_part = next((part for part in email_message.walk() if part.get_content_type() == 'message/delivery-status'), None)
 
         bounced_email = False
@@ -1342,7 +1343,11 @@ class MailThread(models.AbstractModel):
         bounced_msg_id = False
         bounced_message = self.env['mail.message'].sudo()
         if email_part:
-            email_payload = email_part.get_payload()[0]
+            if email_part.get_content_type() == 'text/rfc822-headers':
+                # Convert the message body into a message itself
+                email_payload = message_from_string(email_part.get_payload(), policy=policy.SMTP)
+            else:
+                email_payload = email_part.get_payload()[0]
             bounced_msg_id = tools.mail_header_msgid_re.findall(tools.decode_message_header(email_payload, 'Message-Id'))
             if bounced_msg_id:
                 bounced_message = self.env['mail.message'].sudo().search([('message_id', 'in', bounced_msg_id)])
diff --git a/addons/test_mail/data/test_mail_data.py b/addons/test_mail/data/test_mail_data.py
index fa64fd56e26..d6e38846930 100644
--- a/addons/test_mail/data/test_mail_data.py
+++ b/addons/test_mail/data/test_mail_data.py
@@ -467,6 +467,63 @@ Web: <a class="moz-txt-link-freetext" href="http://www.odoo.com">http://www.odoo
 
 --------------A6B5FD5F68F4D73ECD739009--"""
 
+MAIL_EML_ATTACHMENT_BOUNCE_HEADERS="""\
+Date: Tue, 24 Dec 2019 11:32:07 +0100 (CET)
+MIME-Version: 1.0
+Content-Type: multipart/mixed; boundary=16063919151.b32bE0eD.7
+Content-Transfer-Encoding: 7bit
+Subject: Undelivered Mail Returned to Sender
+From: {email_from}
+To: {to}
+Message-Id: <20191224103207.415713014C@example.com>
+Return-Path: <MAILER-DAEMON>
+Delivered-To: odoo+82240-account.invoice-19177@mycompany.example.com
+Received: by example.com (Postfix) id 415713014C; Tue, 24 Dec
+ 2019 11:32:07 +0100 (CET)
+Auto-Submitted: auto-replied
+
+
+--16063919151.b32bE0eD.7
+MIME-Version: 1.0
+Content-Type: multipart/alternative; boundary=16063919150.2cD3F37.7
+Content-Transfer-Encoding: 7bit
+Content-ID: <16063919152.fD96.7@8f286b7b7880>
+
+
+--16063919150.2cD3F37.7
+Content-Type: text/plain; charset=US-ASCII
+Content-Disposition: inline
+Content-Transfer-Encoding: 8bit
+
+This is the mail system at host example.com.
+
+I'm sorry to have to inform you that your message could not
+be delivered to one or more recipients. It's attached below.
+
+For further assistance, please send mail to postmaster.
+
+If you do so, please include this problem report. You can
+delete your own text from the attached returned message.
+
+
+--16063919151.b32bE0eD.7
+Content-Type: text/rfc822-headers
+Content-Transfer-Encoding: 7bit
+
+Return-Path: <bounce+82240-account.invoice-19177@mycompany.example.com>
+Received: by example.com (Postfix) id 415713014C; Tue, 24 Dec
+Content-Type: multipart/mixed; boundary="===============3600759226158551994=="
+MIME-Version: 1.0
+Message-Id: {msg_id}
+references: <1571814481.189281940460205.799582441238467-openerp-19177-account.invoice@mycompany.example.com>
+Subject: Test
+From: "Test" <noreply+srglvrz-gmail.com@mycompany.example.com>
+Reply-To: "MY COMPANY" <info@mycompany.example.com>
+To: "Test" <test@anothercompany.example.com>
+Date: Tue, 24 Dec 2019 10:32:05 -0000
+X-Odoo-Objects: account.invoice-19177
+
+--16063919151.b32bE0eD.7--"""
 
 MAIL_XHTML = """Return-Path: <xxxx@xxxx.com>
 Received: from xxxx.internal (xxxx.xxxx.internal [1.1.1.1])
diff --git a/addons/test_mail/tests/test_mail_gateway.py b/addons/test_mail/tests/test_mail_gateway.py
index 8c906497176..d3e829248c2 100644
--- a/addons/test_mail/tests/test_mail_gateway.py
+++ b/addons/test_mail/tests/test_mail_gateway.py
@@ -60,6 +60,20 @@ class TestEmailParsing(TestMailCommon):
         mail = self.format(test_mail_data.MAIL_EML_ATTACHMENT, email_from='"Sylvie Lelitre" <test.sylvie.lelitre@agrolait.com>', to='generic@test.com')
         self.env['mail.thread'].message_parse(self.from_string(mail))
 
+    def test_message_parse_eml_bounce_headers(self):
+        # Test Text/RFC822-Headers MIME content-type
+        msg_id = '<861878175823148.1577183525.736005783081055-openerp-19177-account.invoice@mycompany.example.com>'
+        mail = self.format(
+            test_mail_data.MAIL_EML_ATTACHMENT_BOUNCE_HEADERS,
+            email_from='MAILER-DAEMON@example.com (Mail Delivery System)',
+            to='test_bounce+82240-account.invoice-19177@mycompany.example.com',
+            # msg_id goes to the attachment's Message-Id header
+            msg_id=msg_id,
+        )
+        res = self.env['mail.thread'].message_parse(self.from_string(mail))
+
+        self.assertEqual(res['bounced_msg_id'], [msg_id], "Message-Id is not extracted from Text/RFC822-Headers attachment")
+
     def test_message_parse_plaintext(self):
         """ Incoming email in plaintext should be stored as html """
         mail = self.format(test_mail_data.MAIL_TEMPLATE_PLAINTEXT, email_from='"Sylvie Lelitre" <test.sylvie.lelitre@agrolait.com>', to='generic@test.com')