The smtplib.server.sendmail function in python raises UnicodeEncodeError: 'ascii' codec can't encode character

Question

我正在尝试编辑一个文本文件，然后使用 python 脚本将其作为电子邮件正文发送，但我遇到了 unicode 编码错误。经过一些研究，我找到了使用方法 .encode('utf-8') 的解决方案，但这对我不起作用，因为 sendmail() 方法只发送字符串

这是我使用的 python 代码片段：

irtem = open('irtemplate.txt')
data = irtem.read().replace('(name)', eng_name).replace('(customer)', 
cu_name).replace('(sr)', SR_num).replace('(problem)', 
prob_description).replace('(email)', eng_email).replace('(details)', 
details_req).replace('(tele)', eng_tele)


message_text = data
message = "From: %s\r\n" % fromaddr + "To: %s\r\n" % toaddr + "CC: 
%s\r\n" % ",".join(cc) + "Subject: %s\r\n" % message_subject + "\r\n" + 
message_text
toaddrs = [toaddr] + cc + bcc
server.set_debuglevel(1)
server.sendmail(fromaddr, toaddrs, message)
server.quit()

回溯：

Traceback (most recent call last):
File "autoIR.py", line 39, in <module>
server.sendmail(fromaddr, toaddrs, message)
File "/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/smtplib.py", line 855, in sendmail
msg = _fix_eols(msg).encode('ascii')
UnicodeEncodeError: 'ascii' codec can't encode character '\u2019' in 
position 168: ordinal not in range(128)

Answer 1

smtplib.server 的 sendmail 方法需要一个 bytes 实例；如果它得到 str，它会尝试将其编码为 ASCII，如果 str 包含任何 non-ASCII 个字符，则会产生 UnicodeEncodeError。

您可以通过自己对消息进行编码来解决此问题：

>>> msg = 'Hello Wørld'
>>> from_ = 'a@example.com'
>>> to_ = 'b@example.com'
>>> subject = 'Hello'

>>> fmt = 'From: {}\r\nTo: {}\r\nSubject: {}\r\n{}'

>>> server.sendmail(to_, from_, fmt.format(to_, from_, subject, msg).encode('utf-8'))
{}

这将发送此消息*：

b'From: b@example.com'
b'To: a@example.com'
b'Subject: Hello'
b'Hello W\xc3\xb8rld'

但是，如果您想随邮件发送 non-text 二进制数据，则此解决方法将不起作用。

更好的解决方案是使用电子邮件包中的 EmailMessage class。

>>> from email.message import EmailMessage
>>> em = EmailMessage()
>>> em.set_content(msg)
>>> em['To'] = to_
>>> em['From'] = from_
>>> em['Subject'] = subject

>>> # NB call the server's *send_message* method
>>> server.send_message(em)
{}

这发送了这条消息；注意额外的 headers 告诉收件人使用的编码：

b'Content-Type: text/plain; charset="utf-8"'
b'Content-Transfer-Encoding: 8bit'
b'MIME-Version: 1.0'
b'To: to@example.com'
b'From: from@example.com'
b'Subject: Hello'
b'X-Peer: ::1'
b''
b'Hello W\xc3\xb8rld'

* 运行命令 python -m smtpd -n -c DebuggingServer localhost:1025 在单独的终端中捕获消息数据。

The smtplib.server.sendmail function in python raises UnicodeEncodeError: 'ascii' codec can't encode character

The smtplib.server.sendmail function in python raises UnicodeEncodeError: 'ascii' codec can't encode character

python

email

character-encoding

smtplib

python-3.x