1 files changed, 151 insertions, 0 deletions
diff --git a/Biz/EmailAgent.py b/Biz/EmailAgent.py
new file mode 100755
index 0000000..6ac4c95
--- /dev/null
+++ b/Biz/EmailAgent.py
@@ -0,0 +1,151 @@
+#!/usr/bin/env run.sh
+"""
+Email sending utility that can be used as a script or imported as a library.
+
+Password is provided through systemd's LoadCredential feature. This is intended
+to be used by automated agents in a systemd timer.
+"""
+
+import argparse
+import email.message
+import email.utils
+import errno
+import os
+import pathlib
+import smtplib
+import sys
+
+
+# ruff: noqa: PLR0917, PLR0913
+def send_email(
+    to_addrs: list[str],
+    from_addr: str,
+    smtp_server: str,
+    password: str,
+    subject: str,
+    body_text: pathlib.Path,
+    body_html: pathlib.Path | None = None,
+    port: int = 587,
+) -> dict[str, tuple[int, bytes]]:
+    """
+    Send an email using the provided parameters.
+
+    Args:
+        to_addr: Recipient email addresses
+        from_addr: Sender email address
+        smtp_server: SMTP server hostname
+        password: Password for authentication
+        subject: Email subject
+        body_text: File with email body text
+        body_html: File with email body html
+        port: SMTP server port (default: 587)
+
+    """
+    msg = email.message.EmailMessage()
+    msg["Subject"] = subject
+    msg["From"] = from_addr
+    msg["To"] = ", ".join(to_addrs)
+    msg["Message-ID"] = email.utils.make_msgid(
+        idstring=__name__,
+        domain=smtp_server,
+    )
+    msg["Date"] = email.utils.formatdate(localtime=True)
+    with body_text.open(encoding="utf-8") as txt:
+        msg.set_content(txt.read())
+    if body_html:
+        with body_html.open(encoding="utf-*") as html:
+            msg.add_alternative(html.read(), subtype="html")
+    with smtplib.SMTP(smtp_server, port) as server:
+        server.starttls()
+        server.login(from_addr, password)
+        return server.send_message(
+            msg,
+            from_addr=from_addr,
+            to_addrs=to_addrs,
+        )
+
+
+def main() -> None:
+    """Parse command line arguments and send email.
+
+    Raises:
+        FileNotFoundError: if --password-file does not exist
+    """
+    if "test" in sys.argv:
+        sys.exit(0)
+    parser = argparse.ArgumentParser(
+        description="Send an email",
+    )
+    parser.add_argument(
+        "--to",
+        required=True,
+        help="Recipient email addresses, can be specified multiple times",
+        nargs="+",
+        action="extend",
+    )
+    parser.add_argument(
+        "--from",
+        dest="from_addr",
+        required=True,
+        help="Sender email address",
+    )
+    parser.add_argument(
+        "--smtp-server",
+        required=True,
+        help="SMTP server hostname",
+    )
+    parser.add_argument("--subject", required=True, help="Email subject")
+    parser.add_argument(
+        "--body-text",
+        required=True,
+        help="File with email body text",
+    )
+    parser.add_argument(
+        "--body-html",
+        help="File with email body html",
+        default=None,
+    )
+    parser.add_argument(
+        "--port",
+        type=int,
+        default=587,
+        help="SMTP server port (default: 587)",
+    )
+    parser.add_argument(
+        "--password-file",
+        default="smtp-password",
+        help="Where to find the password file",
+    )
+
+    args = parser.parse_args()
+
+    credential_path = pathlib.Path(args.password_file)
+    if not credential_path.exists():
+        raise FileNotFoundError(
+            errno.ENOENT,
+            os.strerror(errno.ENOENT),
+            credential_path,
+        )
+        sys.exit(1)
+
+    with pathlib.Path.open(credential_path, encoding="utf-8") as f:
+        password = f.read().strip()
+
+    results = send_email(
+        to_addrs=args.to,
+        from_addr=args.from_addr,
+        smtp_server=args.smtp_server,
+        subject=args.subject,
+        body_text=pathlib.Path(args.body_text),
+        body_html=pathlib.Path(args.body_html) if args.body_html else None,
+        password=password,
+        port=args.port,
+    )
+    if len(results) > 0:
+        sys.stdout.write(str(results))
+        sys.stdout.flush()
+        sys.exit(1)
+
+
+if __name__ == "__main__":
+    main()