μMail （MicroMail）

一个轻量级，可扩展的SMTP客户端，用于在MicroPython中发送电子邮件。

用法：

最低限度的方法

import umail

smtp = umail.SMTP(‘smtp.gmail.com’, 587, username=’my@gmail.com’, password=’mypassword’)

smtp.to(‘someones@gmail.com’)

smtp.send(“This is an example.”)

smtp.quit()

接口文档：

umail.SMTP(host, port, [ssl, username, password])

主机 - smtp 服务器

端口 - 服务器的端口号

ssl - 在服务器需要 SSL 时设置True

用户名 - 我的用户名/电子邮件到服务器

密码 - 我的密码

SMTP.login（用户名、密码）如果您在初始化服务器时未登录，请在此处进行！

SMTP.to(addrs, mail_from)

地址 - 收件人的电子邮件地址。如果有多个食谱，请使用列表，例如。[‘aaa@mail.com’, ‘bbb@mail.com’]

mail_from - 手动指定 MAIL FROM 地址，默认值为 smtp 用户名。例

SMTP.write（content）要发送长电子邮件或包含大型附件的电子邮件，您很可能会超出MCU的内存限制。

使用此功能将电子邮件分解为较小的块。

每次调用 都会导致将电流发送到服务器，以便您可以加载下一个块。write()content

SMTP.send（[content]）完成电子邮件的编写。

使SMTP服务器实际将您的电子邮件发送到配方地址。

SMTP.quit（）关闭与服务器的连接

用法1：

#    
# An bare minimium example for sending a email    
# without SSL connection    
#    
import umail    
smtp = umail.SMTP('smtp.gmail.com', 587, username='my@gmail.com', password='mypassword')    
smtp.to('someones@gmail.com')    
smtp.send("This is an example.")    
smtp.quit()

用法2：

#    
# Setting the MAIL FROM address    
#    
# Some services may require you to set the MAIL FROM address different than your     
# login username. In such cases, you can manually specify the address by    
# smtp.to(mail_from=address)    
# If argument not set, MAIL FROM address will be default to your login username.    
#    
# Read more about MAIL FROM:    
# https://docs.aws.amazon.com/ses/latest/DeveloperGuide/mail-from.html    
#    
import umail    
smtp = umail.SMTP('email-smtp.us-west-2.amazonaws.com', 587, username='myusername', password='mypassword')    
smtp.to('someones@gmail.com', mail_from='my@gmail.com')    
smtp.send("This is an example.")    
smtp.quit()

用法3：

#    
# An example for sending a long email    
# with SSL connection    
#    
# NOTE:    
# If the email is too long to fit in an variable,    
# you may use write() to send a chunk of the email     
# each time.    
#    
import umail    
smtp = umail.SMTP('smtp.gmail.com', 465, ssl=True) # Gmail's SSL port    
smtp.login('bob@gmail.com', 'bobspassword')    
smtp.to('alice@gmail.com')    
smtp.write("From: Bob <bob@gmail.com>\n")    
smtp.write("To: Alice <alice@gmail.com>\n")    
smtp.write("Subject: Poem\n\n")    
smtp.write("Roses are red.\n")    
smtp.write("Violets are blue.\n")    
smtp.write("...\n")    
smtp.send()    
smtp.quit()

umail.py

# uMail (MicroMail) for MicroPython
# Copyright (c) 2018 Shawwwn <shawwwn1@gmai.com>
# License: MIT
import usocket

DEFAULT_TIMEOUT = 10 # sec
LOCAL_DOMAIN = '127.0.0.1'
CMD_EHLO = 'EHLO'
CMD_STARTTLS = 'STARTTLS'
CMD_AUTH = 'AUTH'
CMD_MAIL = 'MAIL'
AUTH_PLAIN = 'PLAIN'
AUTH_LOGIN = 'LOGIN'

class SMTP:
    def cmd(self, cmd_str):
        sock = self._sock;
        sock.write('%s\r\n' % cmd_str)
        resp = []
        next = True
        while next:
            code = sock.read(3)
            next = sock.read(1) == b'-'
            resp.append(sock.readline().strip().decode())
        return int(code), resp

    def __init__(self, host, port, ssl=False, username=None, password=None):
        import ussl
        self.username = username
        addr = usocket.getaddrinfo(host, port)[0][-1]
        sock = usocket.socket(usocket.AF_INET, usocket.SOCK_STREAM)
        sock.settimeout(DEFAULT_TIMEOUT)
        sock.connect(addr)
        if ssl:
            sock = ussl.wrap_socket(sock)
        code = int(sock.read(3))
        sock.readline()
        assert code==220, 'cant connect to server %d, %s' % (code, resp)
        self._sock = sock

        code, resp = self.cmd(CMD_EHLO + ' ' + LOCAL_DOMAIN)
        assert code==250, '%d' % code
        if not ssl and CMD_STARTTLS in resp:
            code, resp = self.cmd(CMD_STARTTLS)
            assert code==220, 'start tls failed %d, %s' % (code, resp)
            self._sock = ussl.wrap_socket(sock)

        if username and password:
            self.login(username, password)

    def login(self, username, password):
        self.username = username
        code, resp = self.cmd(CMD_EHLO + ' ' + LOCAL_DOMAIN)
        assert code==250, '%d, %s' % (code, resp)

        auths = None
        for feature in resp:
            if feature[:4].upper() == CMD_AUTH:
                auths = feature[4:].strip('=').upper().split()
        assert auths!=None, "no auth method"

        from ubinascii import b2a_base64 as b64
        if AUTH_PLAIN in auths:
            cren = b64("\0%s\0%s" % (username, password))[:-1].decode()
            code, resp = self.cmd('%s %s %s' % (CMD_AUTH, AUTH_PLAIN, cren))
        elif AUTH_LOGIN in auths:
            code, resp = self.cmd("%s %s %s" % (CMD_AUTH, AUTH_LOGIN, b64(username)[:-1].decode()))
            assert code==334, 'wrong username %d, %s' % (code, resp)
            code, resp = self.cmd(b64(password)[:-1].decode())
        else:
            raise Exception("auth(%s) not supported " % ', '.join(auths))

        assert code==235 or code==503, 'auth error %d, %s' % (code, resp)
        return code, resp

    def to(self, addrs, mail_from=None):
        mail_from = self.username if mail_from==None else mail_from
        code, resp = self.cmd(CMD_EHLO + ' ' + LOCAL_DOMAIN)
        assert code==250, '%d' % code
        code, resp = self.cmd('MAIL FROM: <%s>' % mail_from)
        assert code==250, 'sender refused %d, %s' % (code, resp)

        if isinstance(addrs, str):
            addrs = [addrs]
        count = 0
        for addr in addrs:
            code, resp = self.cmd('RCPT TO: <%s>' % addr)
            if code!=250 and code!=251:
                print('%s refused, %s' % (addr, resp))
                count += 1
        assert count!=len(addrs), 'recipient refused, %d, %s' % (code, resp)

        code, resp = self.cmd('DATA')
        assert code==354, 'data refused, %d, %s' % (code, resp)
        return code, resp

    def write(self, content):
        self._sock.write(content)

    def send(self, content=''):
        if content:
            self.write(content)
        self._sock.write('\r\n.\r\n') # the five letter sequence marked for ending
        line = self._sock.readline()
        return (int(line[:3]), line[4:].strip().decode())

    def quit(self):
        self.cmd("QUIT")
        self._sock.close()