Microsoft 365 SMTP

m365_smtp.py

import smtplib
import mimetypes
import os
from email.message import EmailMessage


# References
# https://support.microsoft.com/en-us/office/pop-imap-and-smtp-settings-8361e398-8af4-4e97-b147-6c6c4ac95353
# https://docs.python.org/ko/3/library/email.examples.html#email-examples
# https://developer.mozilla.org/en-US/docs/Web/HTTP/Basics_of_HTTP/MIME_types
# https://developer.mozilla.org/ko/docs/Web/HTTP/Basics_of_HTTP/MIME_types/Common_types


EMAIL_ADDRESS = "M365_EMAIL_ADDRESS"
EMAIL_PASSWORD = "APP_PASSWORD"

M365_SMTP_SERVER = "smtp.office365.com"
M365_SMTP_PORT = 587
M365_SMTP_ENCRYPTION = "STARTTLS"
M365_IMAP_SERVER = "outlook.office365.com"
M365_IMAP_PORT = "993"
M365_IMAP_ENCRYPTION = "SSL/TLS"


to_list = ["[email protected]"]
cc_list = []
bcc_list = []
subject = "메일 제목"
body = "메일 본문"
attach_directory_list = ['attachments']

msg = EmailMessage()
msg["From"] = EMAIL_ADDRESS
msg["To"] = ", ".join(to_list)
if cc_list:
    msg["Cc"] = ", ".join(cc_list)
if bcc_list:
    msg["Bcc"] = ", ".join(bcc_list)
msg["Subject"] = subject
msg.set_content(body)


def attach_files(directory: str) -> None:
    for filename in os.listdir(directory):
        path = os.path.join(directory, filename)
        if not os.path.isfile(path):
            continue
        ctype, encoding = mimetypes.guess_type(filename)
        if ctype is None or encoding is not None:
            ctype = 'application/octet-stream'
        # ['application', 'vnd.openxmlformats-officedocument.spreadsheetml.sheet']
        maintype, subtype = ctype.split('/', 1)
        with open(path, 'rb') as fp:
            # msg.add_attachment(f.read(), maintype="image", subtype="png", filename=f.name)
            msg.add_attachment(fp.read(), maintype=maintype, subtype=subtype, filename=filename)


# Attachments
if attach_directory_list:
    for directory in attach_directory_list:
        attach_files(directory=directory)


with smtplib.SMTP(M365_SMTP_SERVER, M365_SMTP_PORT) as smtp:
    smtp.ehlo()                         # 연결 수립 확인
    smtp.starttls()
    smtp.login(EMAIL_ADDRESS, EMAIL_PASSWORD)
    smtp.send_message(msg)