send uncaught exceptions via email

#!/usr/bin/env python3

"""
Just import this module and change the settings.
Uncaught Exceptions were sent via E-Mail with a thread.

The emails package is required.
"""

import sys
import traceback
from pathlib import Path
from threading import Thread

try:
    from emails import Message
except ImportError:
    raise SystemExit("Please install the emails package\n\npip3 install emails")


class Sender:
    def __init__(
        self, mail_from, mail_to, username, password, host, port, tls, timeout
    ):
        self.smtp = {
            "user": username,
            "password": password,
            "host": host,
            "port": port,
            "timeout": timeout,
            "tls": tls,
        }
        self.mail_to = mail_to
        self.mail_from = mail_from

    def send(self, subject, text):
        Thread(target=self._send, args=(subject, text)).start()

    def _send(self, subject, text):
        return (
            Message(
                subject=subject,
                mail_from=self.mail_from,
                mail_to=self.mail_to,
                text=text,
            )
            .send(smtp=self.smtp)
            .error
        )


def hook(exctype, value, tb):
    tb = "\n".join(traceback.format_exception(exctype, value, tb))
    _sender.send(f"Exception: {exctype}", f"Value: {value}\nTraceback: {tb}\n")


MAIL_FROM = "mail@domain.tld"
MAIL_TO = "mail@domain.tld"
HOST = "smtp.domain.tld"
PORT = 587
TLS = True
TIMEOUT = 5
USERNAME = "mail@domain.tld"
# Password could be stored in a file or you put it into the source,
# which is not a good idea
PASSWORD = Path.home().joinpath(".config/.emailpw").read_text().rstrip()

# make an instance of Sender
_sender = Sender(MAIL_FROM, MAIL_TO, USERNAME, PASSWORD, HOST, PORT, TLS, TIMEOUT)

# replacing the sys.excpthook, which is called, if an uncaught exception occurs.
# the function hook is the replacement

sys.excepthook = hook