send email using python3 smtplib

send_email.py

#!/usr/bin/env python3
import os
import sys
import smtplib
from email.mime.application import MIMEApplication
from email.mime.multipart import MIMEMultipart
from email.mime.text import MIMEText
from email.utils import COMMASPACE

SMTP_ADDR = 'smtp.office365.com'
SMTP_PORT = 587
SMTP_ENC = 'STARTTLS'
SMTP_USER = '[email protected]'
SMTP_PASSWORD = os.environ.get('SMTP_PASSWORD', None)
if SMTP_PASSWORD is None:
    print('没有发件服务器密码，无法自动发布')
    sys.exit(1)

MAIL_CONTENT = '查看附件。'
MAIL_CONTENT_HTML_FILE = 'backend/resume.html'
MAIL_SUBJECT = '简历更新'
MAIL_SENDER = '[email protected]'
MAIL_RECEIVERS = ['[email protected]']
MAIL_ATTACHMENTS = [
        'backend/resume.pdf',
        'backend/resume.en.pdf',
        'backend/resume.md',
        'backend/resume.en.md']

def main():
    try:
        s = smtplib.SMTP(host=SMTP_ADDR, port=SMTP_PORT)
        s.starttls()
    except Exception as e:
        print('failed to connect to smtp host: %s, port: %d, error: %s' % (SMTP_ADDR, SMTP_PORT, e))
        return
    try:
        s.login(SMTP_USER, SMTP_PASSWORD)
    except Exception as e:
        print(
            'failed to login to smtp host: %s, port: %d, user: %s, password: %s, error: %s' %
            (SMTP_ADDR, SMTP_PORT, SMTP_USER, SMTP_PASSWORD, e))
        return
    try:
        msg = MIMEMultipart()
        msg['Subject'] = MAIL_SUBJECT
        msg['From'] = MAIL_SENDER
        msg['To'] = COMMASPACE.join(MAIL_RECEIVERS)
        with open(MAIL_CONTENT_HTML_FILE, "r") as pfile:
            txt = MIMEText(pfile.read(), 'html')
            msg.attach(txt)
        for f in MAIL_ATTACHMENTS:
            with open(f, "rb") as pfile:
                part = MIMEApplication(
                    pfile.read(),
                    Name=os.path.basename(f)
                )
            part['Content-Disposition'] = 'attachment; filename="%s"' % os.path.basename(f)
            msg.attach(part)
        s.sendmail(MAIL_SENDER, MAIL_RECEIVERS, msg.as_string())
    except Exception as e:
        print('failed to send to smtp host: %s, port: %d, user: %s, password: %s, msg: %s, error: %s' %
              (SMTP_ADDR, SMTP_PORT, SMTP_USER, SMTP_PASSWORD, msg.as_string(), e))
    try:
        s.quit()
    except Exception as e:
        print('did send to smtp host: %s, port: %d, user: %s, password: %s, msg: %s, but failed to quit, error: %s' %
              (SMTP_ADDR, SMTP_PORT, SMTP_USER, SMTP_PASSWORD, msg.as_string(), e))
main()