Split multiplart email sending into a dedicated handler (#9977)

Co-authored-by: Andrew Morgan <1342360+anoadragon453@users.noreply.github.com>

1 files changed, 8 insertions, 45 deletions

diff --git a/synapse/push/mailer.py b/synapse/push/mailer.py
index c4b43b0d3f..5f9ea5003a 100644
--- a/synapse/push/mailer.py
+++ b/synapse/push/mailer.py
@@ -12,12 +12,8 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-import email.mime.multipart
-import email.utils
 import logging
 import urllib.parse
-from email.mime.multipart import MIMEMultipart
-from email.mime.text import MIMEText
 from typing import TYPE_CHECKING, Any, Dict, Iterable, List, Optional, TypeVar
 
 import bleach
@@ -27,7 +23,6 @@ from synapse.api.constants import EventTypes, Membership
 from synapse.api.errors import StoreError
 from synapse.config.emailconfig import EmailSubjectConfig
 from synapse.events import EventBase
-from synapse.logging.context import make_deferred_yieldable
 from synapse.push.presentable_names import (
     calculate_room_name,
     descriptor_from_member_events,
@@ -108,7 +103,7 @@ class Mailer:
         self.template_html = template_html
         self.template_text = template_text
 
-        self.sendmail = self.hs.get_sendmail()
+        self.send_email_handler = hs.get_send_email_handler()
         self.store = self.hs.get_datastore()
         self.state_store = self.hs.get_storage().state
         self.macaroon_gen = self.hs.get_macaroon_generator()
@@ -310,17 +305,6 @@ class Mailer:
         self, email_address: str, subject: str, extra_template_vars: Dict[str, Any]
     ) -> None:
         """Send an email with the given information and template text"""
-        try:
-            from_string = self.hs.config.email_notif_from % {"app": self.app_name}
-        except TypeError:
-            from_string = self.hs.config.email_notif_from
-
-        raw_from = email.utils.parseaddr(from_string)[1]
-        raw_to = email.utils.parseaddr(email_address)[1]
-
-        if raw_to == "":
-            raise RuntimeError("Invalid 'to' address")
-
         template_vars = {
             "app_name": self.app_name,
             "server_name": self.hs.config.server.server_name,
@@ -329,35 +313,14 @@ class Mailer:
         template_vars.update(extra_template_vars)
 
         html_text = self.template_html.render(**template_vars)
-        html_part = MIMEText(html_text, "html", "utf8")
-
         plain_text = self.template_text.render(**template_vars)
-        text_part = MIMEText(plain_text, "plain", "utf8")
-
-        multipart_msg = MIMEMultipart("alternative")
-        multipart_msg["Subject"] = subject
-        multipart_msg["From"] = from_string
-        multipart_msg["To"] = email_address
-        multipart_msg["Date"] = email.utils.formatdate()
-        multipart_msg["Message-ID"] = email.utils.make_msgid()
-        multipart_msg.attach(text_part)
-        multipart_msg.attach(html_part)
-
-        logger.info("Sending email to %s" % email_address)
-
-        await make_deferred_yieldable(
-            self.sendmail(
-                self.hs.config.email_smtp_host,
-                raw_from,
-                raw_to,
-                multipart_msg.as_string().encode("utf8"),
-                reactor=self.hs.get_reactor(),
-                port=self.hs.config.email_smtp_port,
-                requireAuthentication=self.hs.config.email_smtp_user is not None,
-                username=self.hs.config.email_smtp_user,
-                password=self.hs.config.email_smtp_pass,
-                requireTransportSecurity=self.hs.config.require_transport_security,
-            )
+
+        await self.send_email_handler.send_email(
+            email_address=email_address,
+            subject=subject,
+            app_name=self.app_name,
+            html=html_text,
+            text=plain_text,
         )
 
     async def _get_room_vars(