由于工作中经常需要收发电子邮件，例如每日（周）的工作报告，测试报告，监控告警，定时提醒等等，大都已电子邮件的形式发送。本文将实现一个 Python 的电子邮件发送类，支持发送多个附件（目录），HTML或纯文本内容，抄送收件人，多个接收者等功能。
代码实现
#!/usr/bin/env python# -*- coding: utf-8 -*-'''Copyright (C) By Thomas Hu. All rights reserved.@author : Thomas Hu@version: 1.0@created: -05-17'''import base64import httplibimport reimport osimport smtplibfrom xml.etree import ElementTreefrom email.utils import formatdatefrom email.MIMEText import MIMETextfrom email.MIMEBase import MIMEBasefrom email.MIMEMultipart import MIMEMultipartfrom email import Encodersclass EmailSender(object):def __init__(self, smtp_server, smtp_port=0, verbose=False, debug_level=1, encoding="utf-8"):''' Initiate the EmailSender.@param smtp_server: the Email SMTP server.@param smtp_port: the Email SMTP server port, if use the default port(25), you can set it to 0 or 25.@param verbose:show the processing information if set to 'True', default is 'False'.@param debug_level: set the smtplib debug level, if it's '0', will enable debug information.@param encoding: the encoding or charset for email body text or attachment file name, default is "utf-8".'''self.server = smtp_serverself.port = int(smtp_port)self.verbose = verboseself.debug_level = int(debug_level)self.encoding = encodingself.attachments = []#Create smtp instanceself.smtp = smtplib.SMTP(self.server, self.port)self.smtp.set_debuglevel(self.debug_level)self.print_verbose("Init SMTP server successfully. server=%s, port=%d."%(self.server, self.port))def print_verbose(self, message):'''Print the verbose information.@param message: the message to be print if the verbose is "True".'''if self.verbose:print(message)def login(self, user, password):'''Login to SMTP server.@param user:the user name of the email sender.@param password: the passord of the user for login to SMTP server.'''self.from_addr = user + "@" + ".".join(self.server.split(".")[1:])try:self.print_verbose("Start to login into SMTP server.server=%s, port=%d."%(self.server, self.port))self.smtp.login(user, password)self.print_verbose("Login into SMTP server successfully.")except Exception as ex:print("Login into SMTP server failed! Error info: %s"%(str(ex)))def __add_attachment_file(self, filename, encoding, Filter):'''Add attachment file to the attachment list.@param filename: the file name of attachment, should not be a path.@param encoding: the encode of the attachment file name.@param Filter: the file filter object, must implement 'accept(filename)' interface, and return True or False.'''# Check if the file is acceptable by the Filterif Filter is not None:try:accept = Filter.accept(filename)except:accept = Falseif accept == False:return# Add the attachment to the attachment listtry:basename = os.path.basename(filename)attach = MIMEBase("application", "octet-stream")attach.set_payload(open(filename, "rb").read())#attach.add_header("Content-Disposition", "attachment;filename=%s"%(basename))attach.add_header("Content-Disposition", "attachment", filename=(encoding, "", basename))Encoders.encode_base64(attach)self.attachments.append(attach)self.print_verbose("Add attachment \"%s\" successfully."%(filename))except Exception as ex:print("Add attachment file \"%s\" failed. Error info: %s."%(filename, str(ex)))def add_attachment(self, path, encoding=None, Filter=None):'''Add attachment file to the attachment list.@param path:the path of files to be added as attachment files. If is a directory, all of the files in it will be added.@param encoding: the encode of the attachment file name.@param Filter: the file filter object, must implement 'accept(filename)' interface, and return True or False.'''if not os.path.exists(path):self.print_verbose("Warning: attachment path \"%s\" is not exists."%(path))returncharset = encoding if (encoding is not None) else self.encodingif os.path.isfile(path):return self.__add_attachment_file(path, charset, Filter)for root, dirs, files in os.walk(path):for f in files:fname = os.path.join(root, f)self.__add_attachment_file(fname, charset, Filter)def send_email(self, subject, to_addrs, cc_addrs, content, subtype="plain", charset=None):'''Send the email to the receivers.@param subject: the email's subject(title).@param to_addrs: the receivers' addresses, it's a list looks like ["user1@", "user2@"].@param cc_addrs: the copy to receivers' addresses, has the same format as to_addrs.@param content: the email message body, it can be plain text or HTML text, which depends on the parameter 'content_type'.@param subtype: the content type, it can be "html" or "plain", default is "plain".@param charset: the charset of message content, default is "None", use the same encoding as the initial function, which default is "utf-8".@return: if send successfully, return 'True', otherwise, return 'False'.'''charset = charset if charset is not None else self.encoding#Set the root informationmsg_root = MIMEMultipart("related")msg_root["Subject"] = subjectmsg_root["From"] = self.from_addr # You can change it to any stringmsg_root["To"] = ",".join(to_addrs)msg_root["CC"] = ",".join(cc_addrs)msg_root["Date"] = formatdate(localtime=True)msg_root.preamble = "This is a multi-part message in MIME format."#Encapsulate the plain and HTML of the message body into an 'alternative' part,#so message agents can decide which they want to display.msg_alt = MIMEMultipart("alternative")#Set the message contentmsg_txt = MIMEText(content, subtype.lower(), charset)msg_alt.attach(msg_txt)#Add the alternative part to root part.msg_root.attach(msg_alt)#Add the attachment filesfor attach in self.attachments:msg_root.attach(attach)#Extend the copy to addresses to to_addrsto_addrs.extend(cc_addrs)#Send the emailtry:self.smtp.sendmail(self.from_addr, to_addrs, msg_root.as_string())self.print_verbose("Send email successfully.")except Exception as ex:print("Send email failed. Error info:%s"%(str(ex)))return Falsereturn Truedef close(self):'''Quit from the SMTP.'''self.smtp.quit()self.print_verbose("Logout SMTP server successfully.")def test():smtp_server = ""user = "yyy"password = "yyyxxx"from_addr = "yyy@"to_addrs = ["xxxxxxxxx@"]cc_addrs = []subject = "Email sending test"content ='Dear Friends,<p/><a href="/thomashtq"> Welcome to my CSDN blog!</a> <p/>Thanks a lot!'attach_files=[r"D:\temp\sendemail\attach"]emailsender = EmailSender(smtp_server, verbose=True)emailsender.login(user, password)for attach in attach_files:emailsender.add_attachment(attach, "utf-8")emailsender.send_email(subject, to_addrs, cc_addrs, content, subtype="html", charset="utf-8")emailsender.close()if __name__ == '__main__':test()
代码中都有详细的解释，请原谅我用英文注释啊，习惯了^_^。 运行时，请将 test() 函数中相关的用户名、密码、服务器、收件人、附件列表等进行修改。也就是 test()函数中开头那段代码（空行之前的），根据自己的具体情况进行修改就 OK 了。
