其他
python实用脚本函数：邮件发送
示例
完整代码
#!/usr/bin/env python3# coding: utf-8
__author__ = 'ChenyangGao <https://chenyanggao.github.io/>'__version__ = (0, 0, 1)__all__ = [ 'make_message', 'make_attachment', 'ctx_smtp', 'sendmail', 'read_file_as_attachment', 'read_textfile_as_attachment', 'make_image', 'attch_image_cites', ]
# Reference:# - [smtplib](https://docs.python.org/3/library/smtplib.html)# - [email](https://docs.python.org/3/library/email.html)# - [email: Examples](https://docs.python.org/3/library/email.examples.html)
from contextlib import contextmanagerfrom email.header import Headerfrom email.message import Messagefrom email.mime.application import MIMEApplicationfrom email.mime.image import MIMEImagefrom email.mime.multipart import MIMEMultipartfrom email.mime.text import MIMETextfrom email.utils import formataddrfrom functools import partial, update_wrapperfrom os import PathLikefrom os.path import basenamefrom re import compile as re_compile, Patternfrom sys import getfilesystemencodingfrom smtplib import SMTP, SMTP_SSLfrom typing import ( cast, Any, Dict, Final, Iterable, Optional, Sequence, SupportsBytes, Tuple, Union, )
# 下面是 邮件地址 的几种可能的模式MAIL_ADDR_CRE: Final[Tuple[Pattern, ...]] = ( re_compile(r'\s*<(?P<addr>(?P<name>[^@]+)@[^> ]+)'), re_compile(r'\s*(?P<name>[^<]+)\s*<(?P<addr>[^> ]+)'), re_compile(r'\s*(?P<addr>(?P<name>[^@]+)@\S+)'),)DEAULT_ATTACHMENT_FILENAME_CHARSET: Final[str] = 'gb18030'DEAULT_ATTACHMENT_FILENAME_LANGUAGE: Final[str] = ''
def extract_addr(mail_addr: str, /) -> str: '尝试从一个邮件地址中提取并返回形如 x@y 的部分，如果失败则原样返回' for cre in MAIL_ADDR_CRE: match = cre.match(mail_addr) if match is not None: return match['addr'] return mail_addr
def format_address(mail_addr: str, /) -> str: '''尝试把一个邮件地址转换成形如'x <y@z>'的格式，如果失败则原样返回''' for cre in MAIL_ADDR_CRE: match = cre.match(mail_addr) if match is not None: break else: return mail_addr return formataddr((match['name'], match['addr']))
def make_addresses(addrs: Union[str, Sequence[str]], /) -> str: '''尝试把一批邮件地址进行格式化，并用';'连接成一个字符串''' if isinstance(addrs, str): return format_address(addrs) return ';'.join(map(format_address, addrs))
def make_message( message: Dict[str, Any], content_type: str = 'plain', encoding: str = 'utf-8', /, **params, ) -> MIMEMultipart: '''创建一个邮件内容对象。
:param message: 邮件的具体内容。 `message`可以有以下这些键名（区分大小写）： From: 发送者 # type: Union[email.header.Header, str] To: 接收者（1个或多个） # type: Union[email.header.Header, Sequence[str]] Cc: 抄送者（1个或多个）(可缺省) # type: Union[email.header.Header, Sequence[str]] Subject: 主题(可缺省) # type: Union[email.header.Header, str] Content: 正文(可缺省) # type: Union[email.message.Message, str] Attachments: 附件（1个或多个）(可缺省) # type: Sequence[Union[ email.message.Message, Tuple[Union[str, bytes], Union[str, Tuple[str, str, str]]] ]] :param content_type: 文本 MIME 类型，会构造为'text/{content_type}'。 :param encoding: 文本编码。 :params params: 其它可以传给`email.mime.multipart.MIMEMultipart`构造方法的参数。
:return: 根据`message`创建的一个`email.mime.multipart.MIMEMultipart`实例。 ''' msg = MIMEMultipart(**params)
msg_from = message['From'] if not isinstance(msg_from, Header): msg['From'] = Header(make_addresses(msg_from), encoding)
msg_to = message['To'] if not isinstance(msg_to, Header): msg['To'] = Header(make_addresses(msg_to), encoding)
msg_cc = message.get('Cc') if msg_cc is not None and not isinstance(msg_cc, Header): msg['Cc'] = Header(make_addresses(msg_cc), encoding)
msg_subject = message.get('Subject') if msg_subject is not None and not isinstance(msg_subject, Header): msg['Subject'] = Header(msg_subject, encoding)
msg_content = message.get('Content') if msg_content is not None: if not isinstance(msg_content, Message): msg_content = MIMEText(msg_content, content_type, encoding) msg.attach(msg_content)
msg_attachments = message.get('Attachments') if msg_attachments is not None: for arg in msg_attachments: if not isinstance(arg, Message): attachment = make_attachment(*arg) msg.attach(attachment)
return msg
def make_attachment( filedata: Union[bytes, str, SupportsBytes], filename: Union[str, Tuple[str, str, str]], /, filename_charset: str = DEAULT_ATTACHMENT_FILENAME_CHARSET, filename_language: str = DEAULT_ATTACHMENT_FILENAME_LANGUAGE, **params, ) -> MIMEApplication: '''创建一个附件内容对象。
:params filedata: 文件的数据。 :params filename: 文件名。如果是`str`，那么会被视为(`filename_charset`, `filename_language`, `filename`)。 :params filename_charset: 文件名的编码。 :params filename_language: 文件名的语言。 :params params: 其它可以传给`email.mime.application.MIMEApplication`构造方法的参数。
:return: 根据参数信息创建的一个`email.mime.application.MIMEApplication`实例。 ''' if isinstance(filedata, str): filedata = filedata.encode() elif not isinstance(filedata, bytes): filedata = bytes(filedata) attachment = MIMEApplication(filedata, **params) if isinstance(filename, str): filename = (filename_charset, filename_language, filename) attachment.add_header('Content-Type', 'application/octet-stream') attachment.add_header('Content-Disposition', 'attachment', filename=filename) return attachment
@contextmanagerdef ctx_smtp( sender: Optional[str] = None, password: str = '', host = None, port: int = None, with_ssl: bool = False, ): '''上下文管理器。 __enter__：创建一个 SMTP 客户端，登录（如果需要），上下文管理器返回`smtplib.SMTP`实例； __exit__： 退出登录（如果在`__enter__`里登录过的话），关闭 SMTP 客户端；
:param sender: 邮件发送者的地址或者名称，也是登录 SMTP 服务器的账号，如果为 None，那么不登录， 并且使用缺省值：'anonymous'。 :param password: 邮件发送者登录SMTP 服务的服务器的口令。 :param host: SMTP 服务的服务器地址。 :param port: SMTP 服务的服务器端口，如果是 None，那么自动指定： 如果`with_ssl`为 False，端口是 25； 如果`with_ssl`为 True，端口是 465； :param with_ssl: 如果为 True，SMTP 客户端是`smtplib.SMTP_SSL`对象，否则是`smtplib.SMTP`对象。 ''' cls = SMTP_SSL if with_ssl else SMTP if port is None: port = 465 if with_ssl else 25 if host is None: smtp = cls() else: smtp = cls(host, port) try: if sender is None: yield (smtp, partial(sendmail, from_addr='anonymous', smtp=smtp)) else: smtp.login(extract_addr(sender), password) try: yield (smtp, partial(sendmail, from_addr=sender, smtp=smtp)) finally: smtp.quit() finally: smtp.close()
def _ensure_smtp(func): def wrapper(*args, smtp=None, **kwargs): if smtp is None: with ctx_smtp(host='localhost', port=0) as (smtp, _): return func(*args, smtp=smtp, **kwargs) else: func(*args, smtp=smtp, **kwargs) return update_wrapper(wrapper, func)
@_ensure_smtpdef sendmail( to_addrs: Union[str, Sequence[str]], *, from_addr: str = 'anonymous', message: Union[bytes, str, Message, Dict[str, Any]] = {'Subject': 'test'}, content_type: str = 'plain', attachments: Optional[Sequence[Any]] = None, smtp: Optional[SMTP] = None, **kwargs, ) -> None: '''发送邮件到一批指定的邮件地址。
:param to_addrs: 接收邮件的地址或地址的序列。 :param from_addr: 发送邮件的地址或者发送者名称。 :param message: 邮件内容。 如果是`bytes`或`str`，那么会作为邮件内容发送出去，即使有`attachments`也不会添加。 如果是`email.message.Message`，那么如果有`attachments`就会添加上去， 然后作为最终邮件内容发送出去。如果是`dict`，那么会补全缺失信息，并添加`attachments`， 再转换成`email.message.Message`，然后作为最终邮件内容发送出去。 作为字典可以有以下这些键名（区分大小写）： From: 发送者(缺省时设为`from_addr`) To: 接收者（1个或多个）(缺省时设为`to_addrs`) Cc: 抄送者（1个或多个）(可缺省) Subject: 主题(可缺省) Content: 正文(可缺省) Attachments: 附件（1个或多个）(可缺省) :param content_type: 正文的文本类型，最终会视为 text/{content_type} 的 MIME 类型。 :param attachments: 附件的序列，只要能添加，就会添加到 message 中。 附件可能是以下格式之一： 如果是`email.message.Message`实例，则作为附件对象直接使用； 如果模式是 (filedata, filename)，则传给`make_attachment`，创建附件对象； 如果模式是 filedata，则会分配一个 filename，然后传给`make_attachment`，创建附件对象； :param smtp: 预期是一个`smtplib.SMTP`实例，如果未提供，则会尝试使用系统中邮件服务， 此时系统中可能启动了诸如 sendmail、postfix、dovecot 这类程序。 ''' smtp = cast(SMTP, smtp) if not to_addrs: raise ValueError('`to_addrs`不能为空') from_addr_: str = extract_addr(from_addr) to_addrs_: Tuple[str, ...] if isinstance(to_addrs, str): to_addrs_ = (extract_addr(to_addrs),) else: to_addrs_ = tuple(map(extract_addr, to_addrs)) if isinstance(message, (bytes, str)): smtp.sendmail(from_addr_, to_addrs_, message, **kwargs) return elif isinstance(message, Message): msg = message elif isinstance(message, dict): message.setdefault('From', from_addr) message.setdefault('To', to_addrs) msg = make_message(message, content_type) else: raise TypeError(f'`message`不支持的邮件类型：{type(message)}') if attachments is not None: for i, attachment in enumerate(attachments, 1): if type(attachment) is tuple: args = attachment attachment = make_attachment(*args) elif not isinstance(attachment, Message): data = attachment filename = '%d.%s' % (i, ('data', 'txt')[isinstance(data, str)]) attachment = make_attachment(data, filename) msg.attach(attachment) smtp.sendmail(from_addr_, to_addrs_, msg.as_string(), **kwargs)
def read_file_as_attachment( path: Union[str, PathLike], filename: Union[None, str, Tuple[str, str, str]] = None, filename_charset: str = DEAULT_ATTACHMENT_FILENAME_CHARSET, filename_language: str = DEAULT_ATTACHMENT_FILENAME_LANGUAGE, ) -> MIMEApplication: '读取一个文件作为附件' if filename is None: filename = basename(path) return make_attachment( open(path, 'rb').read(), filename, filename_charset=filename_charset, filename_language=filename_language, )
def read_textfile_as_attachment( path: Union[str, PathLike], filename: Union[None, str, Tuple[str, str, str]] = None, filename_charset: str = DEAULT_ATTACHMENT_FILENAME_CHARSET, filename_language: str = DEAULT_ATTACHMENT_FILENAME_LANGUAGE, ) -> MIMEText: '读取一个文本文件作为附件' if filename is None: filename = basename(path) attachment = MIMEText( open(path, 'rb').read(), # type: ignore 'base64', getfilesystemencoding(), ) if isinstance(filename, str): filename = (filename_charset, filename_language, filename) attachment.add_header('Content-Type', 'application/octet-stream') attachment.add_header('Content-Disposition', 'attachment', filename=filename) return attachment
def make_image( image: Union[bytes, str, PathLike], cid: Any = None, ) -> MIMEImage: '创建一个图片对象，或可作为引用(`cid`不是`None`)' if not isinstance(image, bytes): image = open(image, 'rb').read() mime_image = MIMEImage(image) if cid is None: mime_image.add_header('Content-ID', '<%s>' % cid) return mime_image
def attch_image_cites( cid_image_pairs: Iterable[Tuple[Any, Union[bytes, str, PathLike]]], content_root: Optional[MIMEMultipart] = None,): '使用一批图片作为引用，并附加到一个内容对象上' if content_root is None: content_root = MIMEMultipart('alternative') for cid, image in cid_image_pairs: mime_image = make_image(image, cid) content_root.attach(mime_image) return content_root
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