From 7598a167d057f136daedbd8e754e1d0f71f798ef Mon Sep 17 00:00:00 2001
From: Son NK <nguyenkims@hotmail.com>
Date: Tue, 11 Feb 2020 22:58:30 +0700
Subject: [PATCH] Improve emails that inform unauthorized user

---
 app/email_utils.py                                   |  2 +-
 email_handler.py                                     |  9 +++++++--
 .../send-from-alias-from-unknown-sender.txt          | 12 ++++++++++++
 3 files changed, 20 insertions(+), 3 deletions(-)
 create mode 100644 templates/emails/transactional/send-from-alias-from-unknown-sender.txt

diff --git a/app/email_utils.py b/app/email_utils.py
index 096ce13d..8a13b127 100644
--- a/app/email_utils.py
+++ b/app/email_utils.py
@@ -186,7 +186,7 @@ def send_email(to_email, subject, plaintext, html):
     msg["To"] = to_email
 
     msg.set_content(plaintext)
-    if html is not None:
+    if html:
         msg.add_alternative(html, subtype="html")
 
     msg_id_header = make_msgid()
diff --git a/email_handler.py b/email_handler.py
index afe66159..a5c63e4a 100644
--- a/email_handler.py
+++ b/email_handler.py
@@ -348,10 +348,15 @@ class MailHandler:
                 ),
             )
 
+            # Notify sender that they cannot send emails to this address
             send_email(
                 envelope.mail_from,
-                f"Your email ({envelope.mail_from}) is not allowed to send email to {reply_email}",
-                "",
+                f"Your email ({envelope.mail_from}) is not allowed to send emails to {reply_email}",
+                render(
+                    "transactional/send-from-alias-from-unknown-sender.txt",
+                    sender=envelope.mail_from,
+                    reply_email=reply_email,
+                ),
                 "",
             )
 
diff --git a/templates/emails/transactional/send-from-alias-from-unknown-sender.txt b/templates/emails/transactional/send-from-alias-from-unknown-sender.txt
new file mode 100644
index 00000000..992ebaca
--- /dev/null
+++ b/templates/emails/transactional/send-from-alias-from-unknown-sender.txt
@@ -0,0 +1,12 @@
+Hi,
+
+This is an automated email from SimpleLogin.
+
+We have recorded an attempt to send an email from your email ({{sender}}) to {{reply_email}}.
+
+{{reply_email}} is a special email address that only receive emails from its authorized user.
+
+If you have any question, you can contact us by replying to this email or consult our website at https://simplelogin.io.
+
+Regards,
+SimpleLogin team.