python 邮件脚本 - 添加 zip

python mailing script - adding zip

我想寻求有关向我用于发送报告的邮件脚本添加 zip 选项的建议。

我将电子邮件附件限制设置为 25MB,因此一些 json 格式的超过 25MB 的报告会被邮件程序丢弃。我想添加一个 zip 支持,如果附件比 ex 大,它将压缩附件。 15MB.

以下代码仅为邮件部分。

import smtplib
from email.mime.text import MIMEText
from email.mime.multipart import MIMEMultipart
from email.mime.application import MIMEApplication
from email.mime.text import MIMEText
from email.utils import COMMASPACE
import sys
from os.path import basename
import argparse
import conf
import os
import zipfile
import zlib

###############################################################################
# Mailer function for server running environment

def send_mail(recipients, cc=None, subject=None, attachment=None, body=None, send_from=None): 
    msg = MIMEMultipart()
    msg['Subject'] = subject
    msg['From'] = send_from
    msg['To'] = ','.join(recipients)
    if cc:
        msg['CC'] = ','.join(cc)
        recipients.extend(cc)
    if body:
        text = MIMEText(body, 'html')
        msg.attach(text)
    if attachment:
        with open(attachment, 'rb') as fp:
            att = MIMEApplication(fp.read(), Name=basename(attachment))
        att['Content-Disposition'] = f'attachment; filename="{basename(attachment)}"'
        msg.attach(att)

    smtp = smtplib.SMTP(conf.RELAY)
    smtp.sendmail(send_from, recipients, msg.as_string())
    smtp.quit()

如果要压缩附件,可以使用zipfile模块压缩文件。

import zipfile
import tempfile
from email import encoders
from email.message import Message
from email.mime.base import MIMEBase
from email.mime.multipart import MIMEMultipart 

...
if attachment:
    zf = tempfile.TemporaryFile(prefix='mail', suffix='.zip')
    zip = zipfile.ZipFile(zf, 'w')
    zip.write(attachment)
    zip.close()
    zf.seek(0)
    att = MIMEBase('application', 'zip')
    att.set_payload(zf.read())
    encoders.encode_base64(att)
    att.add_header('Content-Disposition', 'attachment', filename=the_file + '.zip')
    msg.attach(att)
...

假设您已经拥有的代码正确地附加了任意附件,包括二进制附件,那么下面应该压缩一个大于 15M 的附件。例如,如果原始文件的基本名称为 test.dat,则附件存档名称将为 test.dat.zip 并将包含 test.dat 作为隐式使用 zlib 的单个压缩文件。由于使用了内存缓冲区,因此不需要临时文件。因此,如果附件不是特别大,这应该非常有效:

    if attachment:
        MAX_ATTACHMENT_SIZE = 15 * 1024 * 1024
        with open(attachment, 'rb') as fp:
            bytes = fp.read()
        attachment_name = basename(attachment)
        if len(bytes) > MAX_ATTACHMENT_SIZE:
            from io import BytesIO
            buffer = BytesIO()
            with zipfile.ZipFile(buffer, 'w', compression=zipfile.ZIP_DEFLATED) as zip_file:
                zip_file.writestr(attachment_name, bytes)
            # New attachment name and new data:
            attachment_name += '.zip'
            bytes = buffer.getvalue()            
        att = MIMEApplication(bytes, Name=attachment_name)
        att['Content-Disposition'] = f'attachment; filename="{attachment_name}"'
        msg.attach(att)