如何使用 Python 发送电子邮件？

Question

此代码可以正常工作并向我发送电子邮件：

 import smtplib
#SERVER = "localhost"

FROM = '[e-mail]'

TO = ["[e-mail]"] # must be a list

SUBJECT = "Hello!"

TEXT = "This message was sent with Python's smtplib."

# Prepare actual message

message = """\
From: %s
To: %s
Subject: %s

%s
""" % (FROM, ", ".join(TO), SUBJECT, TEXT)

# Send the mail

server = smtplib.SMTP('myserver')
server.sendmail(FROM, TO, message)
server.quit()

但是，如果我尝试将其包装在这样的函数中：

 def sendMail(FROM,TO,SUBJECT,TEXT,SERVER):
    import smtplib
    """this is some test documentation in the function"""
    message = """\
        From: %s
        To: %s
        Subject: %s
        %s
        """ % (FROM, ", ".join(TO), SUBJECT, TEXT)
    # Send the mail
    server = smtplib.SMTP(SERVER)
    server.sendmail(FROM, TO, message)
    server.quit()

并称之为我收到以下错误：

  Traceback (most recent call last):
  File "C:/Python31/mailtest1.py", line 8, in <module>
    sendmail.sendMail(sender,recipients,subject,body,server)
  File "C:/Python31\sendmail.py", line 13, in sendMail
    server.sendmail(FROM, TO, message)
  File "C:\Python31\lib\smtplib.py", line 720, in sendmail
    self.rset()
  File "C:\Python31\lib\smtplib.py", line 444, in rset
    return self.docmd("rset")
  File "C:\Python31\lib\smtplib.py", line 368, in docmd
    return self.getreply()
  File "C:\Python31\lib\smtplib.py", line 345, in getreply
    raise SMTPServerDisconnected("Connection unexpectedly closed")
smtplib.SMTPServerDisconnected: Connection unexpectedly closed

谁能帮我理解为什么？

原文由 cloud311 发布，翻译遵循 CC BY-SA 4.0 许可协议

Answer 1

我建议您一起使用标准包 email 和 smtplib 发送电子邮件。请查看以下示例（转载自 Python 文档）。请注意，如果您采用这种方法，“简单”任务确实很简单，而更复杂的任务（如附加二进制对象或发送纯/HTML 多部分消息）可以非常快速地完成。

 # Import smtplib for the actual sending function
import smtplib

# Import the email modules we'll need
from email.mime.text import MIMEText

# Open a plain text file for reading.  For this example, assume that
# the text file contains only ASCII characters.
with open(textfile, 'rb') as fp:
    # Create a text/plain message
    msg = MIMEText(fp.read())

# me == the sender's email address
# you == the recipient's email address
msg['Subject'] = 'The contents of %s' % textfile
msg['From'] = me
msg['To'] = you

# Send the message via our own SMTP server, but don't include the
# envelope header.
s = smtplib.SMTP('localhost')
s.sendmail(me, [you], msg.as_string())
s.quit()

要向多个目的地发送电子邮件，您还可以按照 Python 文档 中的示例进行操作：

 # Import smtplib for the actual sending function
import smtplib

# Here are the email package modules we'll need
from email.mime.image import MIMEImage
from email.mime.multipart import MIMEMultipart

# Create the container (outer) email message.
msg = MIMEMultipart()
msg['Subject'] = 'Our family reunion'
# me == the sender's email address
# family = the list of all recipients' email addresses
msg['From'] = me
msg['To'] = ', '.join(family)
msg.preamble = 'Our family reunion'

# Assume we know that the image files are all in PNG format
for file in pngfiles:
    # Open the files in binary mode.  Let the MIMEImage class automatically
    # guess the specific image type.
    with open(file, 'rb') as fp:
        img = MIMEImage(fp.read())
    msg.attach(img)

# Send the email via our own SMTP server.
s = smtplib.SMTP('localhost')
s.sendmail(me, family, msg.as_string())
s.quit()

如您所见， MIMEText 对象中的标题 To 必须是由逗号分隔的电子邮件地址组成的字符串。另一方面， sendmail 函数的第二个参数必须是一个字符串列表（每个字符串都是一个电子邮件地址）。

因此，如果您有三个电子邮件地址： [e-mail] 、 [e-mail] 和 [e-mail] ，您可以执行以下操作（省略明显的部分）：

 to = ["[e-mail]", "[e-mail]", "[e-mail]"]
msg['To'] = ",".join(to)
s.sendmail(me, to, msg.as_string())

",".join(to) 部分从列表中生成一个字符串，用逗号分隔。

根据您的问题，我了解到您还没有阅读 Python 教程- 如果您想了解 Python 的任何地方，这是必须的 - 文档对于标准库来说非常好。

原文由 Escualo 发布，翻译遵循 CC BY-SA 4.0 许可协议

Answer 2

当我需要用 Python 发送邮件时，我使用 mailgun API，它在发送邮件时遇到了很多麻烦。他们有一个很棒的应用程序/API，可以让您每月发送 5,000 封免费电子邮件。

发送电子邮件将是这样的：

 def send_simple_message():
    return requests.post(
        "https://api.mailgun.net/v3/YOUR_DOMAIN_NAME/messages",
        auth=("api", "YOUR_API_KEY"),
        data={"from": "Excited User <mailgun@YOUR_DOMAIN_NAME>",
              "to": ["[e-mail]", "YOU@YOUR_DOMAIN_NAME"],
              "subject": "Hello",
              "text": "Testing some Mailgun awesomness!"})

您还可以跟踪事件等等，请参阅 快速入门指南。

原文由 DDecoene 发布，翻译遵循 CC BY-SA 4.0 许可协议