mail notification

app/notifications/emailer.py

@@ -0,0 +1,42 @@
+from __future__ import annotations
+
+import smtplib
+from email.message import EmailMessage
+
+
+class EmailNotifier:
+    def __init__(
+        self,
+        *,
+        host: str | None,
+        port: int,
+        username: str | None,
+        password: str | None,
+        from_address: str | None,
+        use_tls: bool,
+    ) -> None:
+        self.host = host
+        self.port = port
+        self.username = username
+        self.password = password
+        self.from_address = from_address
+        self.use_tls = use_tls
+
+    @property
+    def configured(self) -> bool:
+        return bool(self.host and self.from_address)
+
+    def send(self, *, to_address: str, subject: str, body: str) -> None:
+        if not self.configured:
+            return
+        message = EmailMessage()
+        message["Subject"] = subject
+        message["From"] = self.from_address
+        message["To"] = to_address
+        message.set_content(body)
+        with smtplib.SMTP(self.host, self.port, timeout=10) as smtp:
+            if self.use_tls:
+                smtp.starttls()
+            if self.username and self.password:
+                smtp.login(self.username, self.password)
+            smtp.send_message(message)