python - 如何向国际地址发送电子邮件

Question

如何通过 smtplib 向国际地址发送电子邮件在Python 中？

如果我使用以下代码

    try:
        server = None

        msg = MIMEMultipart('alternative')
        msg['From'] = formataddr((from_email_name, from_email))
        msg['To'] = Header(to_email, 'utf-8')
        msg['Subject'] = Header(subject, 'utf-8')

        plain_text_part = MIMEText(plain_text_body, 'plain', _charset='utf-8')
        msg.attach(plain_text_part)

        html_part = MIMEText(html_body, 'html', _charset='utf-8')
        msg.attach(html_part)

        server = smtplib.SMTP(smtp_server)
        server.starttls()
        server.login(from_email, from_email_password)
        server.sendmail(from_email, to_email, msg.as_string())
    finally:
        if server is not None:
            server.quit()

然后，当我使用 ñoñó<a href="https://stackoverflow.com/cdn-cgi/l/email-protection" class="__cf_email__" data-cfemail="cdfcfffef98dbea8bfbba8bfe3aea2a0" rel="noreferrer noopener nofollow">[email protected]</a> 调用此代码时，脚本在下一行失败电子邮件作为目标地址 (to_email):

server.sendmail(from_email, to_email, msg.as_string())

输出

'ascii' codec can't encode character u'\xf1' in position 9: ordinal not in range(128)

但是如果我更改 sendmail函数调用如下

server.sendmail(from_email, to_email.encode('utf-8'), msg.as_string())

它失败并出现以下错误:

{'\xc3\xb1o\xc3\xb1\xc3\[email protected]': (555, '5.5.2 Syntax error. i7sm368361lbo.39 - gsmtp')}

我正在使用 GMail 的 SMTP 服务器发送这些电子邮件。

如何修复它？

提前致谢。

Answer 1

RFC 6533 - Overview and Framework for Internationalized Email 指出服务器端:

An SMTP relay MUST

• Either recognize the format explicitly, agreeing to do so via an ESMTP option, or
• Reject the message or, if necessary, return a non-delivery notification message, so that the sender can make another plan.

还有 RFC 6531 - SMTP Extension for Internationalized Email 表示为精度(摘录):

• The EHLO keyword value associated with this extension is "SMTPUTF8"
• One OPTIONAL parameter, SMTPUTF8, is added to the MAIL command.
• If the envelope or message being sent requires the capabilities of the SMTPUTF8 extension, the SMTPUTF8-aware SMTP client MUST supply the SMTPUTF8 parameter with the MAIL command.

由于与 GMail SMTP 服务器的交换痕迹证明它声明自己是 SMTPUTF8 兼容服务器，因此您只需要求 smtplib 提供 SMTPUTF8 选项即可邮件命令。您只需将sendmail命令更改为:

server.sendmail(from_email, to_email.encode('utf-8'), msg.as_string(), ['SMTPUTF8'])

由于您已经处理了正文中最终的非 ASCII 字符，并使用 MIMEMultipart 和 MIMEText 设置了适当的 header ，所以一切都应该没问题。