未收到 SMTPlib 附件

Question

我一直在使用基于 http://datamakessense.com/easy-scheduled-emailing-with-python-for-typical-bi-needs/ 中的代码片段的代码，通过我公司的电子邮件向客户发送 PDF 附件。我们一次通过一个电子邮件地址 ("no-reply@companyname.com") 发送大约 100 封这样的电子邮件，并且对于发送的每封电子邮件，我也会将密件抄送副本发送到一个内部电子邮件地址 ("reports@companyname.com")。

有时（大约 100 人中有 5 人），客户报告没有收到附件。有时根本不显示，有时显示时带有红色问号。但是，BCC 副本总是有附件，没有问题，进入发送帐户，电子邮件的发送副本总是显示附件，也没有问题。没有收到附件的客户邮件没有明显的相似之处（比如共享域；实际上大部分都是@gmail.com）。没有要报告的异常或错误。一切看起来都在正常工作。

这是我第一次使用 MIME 或通过 Python 自动发送电子邮件，但它 98% 的时间都在工作，这让我感到困惑。是否有可能发生这种情况的已知原因？也许我没有正确设置类型？或者我应该为 Gmail 使用 MIME 做些什么？

这是我的代码：

wdir = 'PDFs\'
filelist = []
for file in os.listdir(wdir):
    if file.endswith('.pdf'):
        filelist += [wdir + file]  # sending all of the PDFs in a local directory

email = {}
rf = wdir + 'Reports_data.csv'  # get email addresses for customers by ID (row[2])
with open(rf, 'rbU') as inf:
    read = csv.reader(inf)
    read.next()
    for row in read:
        email[row[2]] = row[3]

hfi = open('HTML\email.html', 'rb')  # the HTML for the email body, itself
htmltxt = hfi.read()
hfi.close()


class Bimail:
    def __init__(self, subject, recipients):
        self.subject = subject
        self.recipients = recipients
        self.htmlbody = ''
        self.sender = "foo@bar.com"
        self.senderpass = 'password'
        self.attachments = []

    def send(self):
        msg = MIMEMultipart('alternative')
        msg['From'] = self.sender
        msg['Subject'] = self.subject
        msg['To'] = self.recipients[0]  
        msg.preamble = "preamble goes here"
        if self.attachments:
            self.attach(msg)
        msg.attach(MIMEText(self.htmlbody, 'html'))
        s = smtplib.SMTP('smtp.gmail.com:587')
        s.starttls()
        s.login(self.sender, self.senderpass)
        s.sendmail(self.sender, self.recipients, msg.as_string())
        s.quit()

    def htmladd(self, html):
        self.htmlbody = self.htmlbody + '<p></p>' + html

    def attach(self, msg):
        for f in self.attachments:    
            ctype, encoding = mimetypes.guess_type(f)
            if ctype is None or encoding is not None:
                ctype = "application/octet-stream"
            maintype, subtype = ctype.split("/", 1)
            fn = f.replace(wdir, '')
            fp = open(f, "rb")
            attachment = MIMEBase(maintype, subtype)
            attachment.set_payload(fp.read())
            fp.close()
            encoders.encode_base64(attachment)
            attachment.add_header("Content-Disposition", "attachment", filename=fn)
            attachment.add_header('Content-ID', '<{}>'.format(f))  # or should this be format(fn)?
            msg.attach(attachment)

    def addattach(self, files):
        self.attachments = self.attachments + files


if __name__ == '__main__':
    for fi in filelist:
        code = fi.split('_')[1].split('\')[1]  # that "ID" for email is in the filename
        addr = email[code]
        mymail = Bimail(('SUBJECT HERE'), [addr, 'reports@ourcompany.com'])
        mymail.htmladd(htmltxt)
        mymail.addattach([fi])
        mymail.send()

Answer 1

试试这个代码块：

import smtplib
from email.MIMEMultipart import MIMEMultipart
from email.MIMEText import MIMEText
from email.MIMEBase import MIMEBase
from email import encoders

fromaddr = "from@yourcompany.com"
password = "password"
toaddr = "to@yourcompany.com"

msg = MIMEMultipart()

msg['From'] = fromaddr
msg['To'] = toaddr
msg['Subject'] = "Report"

body = "Hi, have a look at the Report"

msg.attach(MIMEText(body, 'plain'))

filename = "Report.pdf"
attachment = open("Report.pdf", "rb")

part = MIMEBase('application', 'octet-stream')
part.set_payload((attachment).read())
encoders.encode_base64(part)
part.add_header('Content-Disposition', "attachment; filename= %s" % filename)

msg.attach(part)

server = smtplib.SMTP('smtp.office365.com', 587)
server.starttls()
server.login(fromaddr, "password")
text = msg.as_string()
server.sendmail(fromaddr, toaddr, text)
server.quit()

对我有用

Answer 2

每封电子邮件发送近 100 个附件并不是每个人每天都习惯做的事情，您是否检查过 google SMTP 服务器端没有限制？

以下问题与 "Gmail sending limits in G Suite" 有关，但在我看来，类似的规则适用于任何其他 gmail 帐户。

https://support.google.com/a/answer/2956491#sendinglimitsforrelay

https://support.google.com/a/answer/166852?hl=en

请看下面我的发送邮件功能：

def sendMail(to, subject, text, files=[],server="smtp.gmail.com:587",username="contact.name",password="mygmailurrentpassord"):
    assert type(to)==list
    assert type(files)==list
    fro = "Contact Name <contact.name@gmail.com>"
    msg = MIMEMultipart()
    msg['From'] = fro
    msg['To'] = COMMASPACE.join(to)
    msg['Date'] = formatdate(localtime=True)
    msg['Subject'] = subject
    msg.attach( MIMEText(text) )    
    for file in files:
        part = MIMEBase('application', "octet-stream")
        part.set_payload( open(file,"rb").read() )
        Encoders.encode_base64(part)
        part.add_header('Content-Disposition', 'attachment; filename="%s"'
                       % os.path.basename(file))
        msg.attach(part)    
    smtp = smtplib.SMTP(server) 
    smtp.starttls()  
    smtp.login(username,password)
    smtp.sendmail(fro, to, msg.as_string() )
    smtp.close()

此致

未收到 SMTPlib 附件

SMTPlib Attachments not received

python

email

mime

smtplib