Django邮件发送详解：从send_mail到Backend底层机制

def send_mail(subject, message, from_email, recipient_list,
       fail_silently=False, auth_user=None, auth_password=None,
       connection=None, html_message=None):
  pass     
  
      
def send_mass_mail(datatuple, fail_silently=False, auth_user=None,
          auth_password=None, connection=None):
  pass

# 参数介绍  
# subject: 邮件主题 
# message: 邮件内容 
# from_email: 发件人 
# recipient_list: 收件人，这是一个列表，可以有多个收件人 
# 以上4个在参数 在send_mass_mail中，会写在datatuple这个元组中 
# fail_silently: 是否报错，True的话表忽略异常 
# auth_user&auth_password:账号密码 
# connection: 表示这个的链接对象，后续会提到 
# html_message: send_mail方法独有，可以比较简单地实现一个html文本的传输，具体我也没使用过，不是很了解。

# settings.py
# 我使用的是新浪的，host可以在对应邮箱的设置中找到
EMAIL_HOST = 'smtp.sina.com'
EMAIL_PORT = 25
# 你的邮箱账号与密码
EMAIL_HOST_USER = 'viptestfordjango@sina.com'
EMAIL_HOST_PASSWORD = '******'
# 由于使用25端口，一般都不使用TLS机密，SSL和TSL只需要设置一个，他们同时为True或False
EMAIL_USE_TLS = False
# 发件人，只有这个变量名可以自己自定义，设置在这里是为了减少每次去写
EMAIL_FROM = 'viptestfordjango@sina.com'

from django.core.mail import send_mail, send_mass_mail
from string import lowercase,uppercase,digits
from random import randint
from project.settings import EMAIL_FROM
def send_code_email(email)：
  """
  发送验证码
  """
  # 0-9 a-z A-z
  code = ''
  seeds= lowercase+uppercase+digits
  length = len(seeds)
  # 生成4位验证码
  for i in range(4):
    code += seeds[randint(0, length-1)]
  send_title = '重置密码'
  send_message = '你的验证码是:{0}。'.format(code)
  send_status = send_mail(email_title, email_body, EMAIL_FROM, [email])


def send_hello_email(email1, email2):
  """
  给email1发送 新年好
  给email2发送 Happy New Year
  """
  # message格式(subject, message, from_email, recipient_list)
  message1 = ('新年好', '新年好', 'EMAIL_FROM', [email])
  message2 = ('Happy New Year', 'Happy New Year', EMAIL_FROM, [email2])
  send_status=send_mass_mail((message1, message2), fail_silently=False)

# 类定义
class EmailMessage(object):
  def __init__(self, subject='', body='', from_email=None, to=None, bcc=None,
         connection=None, attachments=None, headers=None, cc=None,
         reply_to=None):
  pass
  
# 使用
from django.core.mail import EmailMessage

email = EmailMessage(
  'Hello',
  'Body goes here',
  'from@example.com',
  ['to1@example.com', 'to2@example.com'],
  ['bcc@example.com'],
  reply_to=['another@example.com'],
  headers={'Message-ID': 'foo'},
)

from django.core import mail

with mail.get_connection() as connection:
  mail.EmailMessage(
    subject1, body1, from1, [to1],
    connection=connection,
  ).send()
  mail.EmailMessage(
    subject2, body2, from2, [to2],
    connection=connection,
  ).send()

from django.core import mail

connection = mail.get_connection()
# get_EmailMessage_list返回一个EmailMessage对象的列表
messages = get_EmailMessage_list()
connection.send_messages(messages)

from django.core import mail

connection = mail.get_connection()
connection.open()

email1 = mail.EmailMessage(
  'Hello',
  'Body goes here',
  'from@example.com',
  ['to1@example.com'],
  connection=connection,
)
email1.send() 

email2 = mail.EmailMessage(
  'Hello',
  'Body goes here',
  'from@example.com',
  ['to2@example.com'],
)
email3 = mail.EmailMessage(
  'Hello',
  'Body goes here',
  'from@example.com',
  ['to3@example.com'],
)
connection.send_messages([email2, email3])

connection.close()

# 在django.core.mail。backends.smtp.下
class EmailBackend(BaseEmailBackend):

  def __init__(self, host=None, port=None, username=None, password=None,
         use_tls=None, fail_silently=False, use_ssl=None, timeout=None,
         ssl_keyfile=None, ssl_certfile=None,**kwargs):
    pass

EMAIL_BACKEND = 'django.core.mail.backends.dummy.EmailBackend'