通过gmail和python发送电子邮件

Question

使用gmail和python发送电子邮件的推荐方法是什么？

有很多SO线程,但大多数都是旧的,并且用户名和密码的smtp不再工作或用户必须降级他们的Gmail的安全性(例如见这里).

OAuth是推荐的方式吗？

Answer 1

答案显示了如何使用gmail API和python发送电子邮件.还更新了发送带附件的电子邮件的答案.

Gmail API和OAuth - >无需在脚本中保存用户名和密码.

脚本第一次打开浏览器以授权脚本并在本地存储凭据(它不会存储用户名和密码).后续运行不需要浏览器,可以直接发送电子邮件.

使用此方法,您将不会收到类似于以下SMTPException的错误,并且不需要为不太安全的应用程序允许Access:

raise SMTPException("SMTP AUTH extension not supported by server.")  
smtplib.SMTPException: SMTP AUTH extension not supported by server.

以下是使用gmail API发送电子邮件的步骤:

(向导链接在这里,更多信息在这里)

第2步:安装Google客户端库

pip install --upgrade google-api-python-client

第3步:使用以下脚本发送电子邮件(只需更改main函数中的变量)

import httplib2
import os
import oauth2client
from oauth2client import client, tools, file
import base64
from email.mime.multipart import MIMEMultipart
from email.mime.text import MIMEText
from apiclient import errors, discovery
import mimetypes
from email.mime.image import MIMEImage
from email.mime.audio import MIMEAudio
from email.mime.base import MIMEBase

SCOPES = 'https://www.googleapis.com/auth/gmail.send'
CLIENT_SECRET_FILE = 'client_secret.json'
APPLICATION_NAME = 'Gmail API Python Send Email'

def get_credentials():
    home_dir = os.path.expanduser('~')
    credential_dir = os.path.join(home_dir, '.credentials')
    if not os.path.exists(credential_dir):
        os.makedirs(credential_dir)
    credential_path = os.path.join(credential_dir,
                                   'gmail-python-email-send.json')
    store = oauth2client.file.Storage(credential_path)
    credentials = store.get()
    if not credentials or credentials.invalid:
        flow = client.flow_from_clientsecrets(CLIENT_SECRET_FILE, SCOPES)
        flow.user_agent = APPLICATION_NAME
        credentials = tools.run_flow(flow, store)
        print('Storing credentials to ' + credential_path)
    return credentials

def SendMessage(sender, to, subject, msgHtml, msgPlain, attachmentFile=None):
    credentials = get_credentials()
    http = credentials.authorize(httplib2.Http())
    service = discovery.build('gmail', 'v1', http=http)
    if attachmentFile:
        message1 = createMessageWithAttachment(sender, to, subject, msgHtml, msgPlain, attachmentFile)
    else: 
        message1 = CreateMessageHtml(sender, to, subject, msgHtml, msgPlain)
    result = SendMessageInternal(service, "me", message1)
    return result

def SendMessageInternal(service, user_id, message):
    try:
        message = (service.users().messages().send(userId=user_id, body=message).execute())
        print('Message Id: %s' % message['id'])
        return message
    except errors.HttpError as error:
        print('An error occurred: %s' % error)
        return "Error"
    return "OK"

def CreateMessageHtml(sender, to, subject, msgHtml, msgPlain):
    msg = MIMEMultipart('alternative')
    msg['Subject'] = subject
    msg['From'] = sender
    msg['To'] = to
    msg.attach(MIMEText(msgPlain, 'plain'))
    msg.attach(MIMEText(msgHtml, 'html'))
    return {'raw': base64.urlsafe_b64encode(msg.as_string())}

def createMessageWithAttachment(
    sender, to, subject, msgHtml, msgPlain, attachmentFile):
    """Create a message for an email.

    Args:
      sender: Email address of the sender.
      to: Email address of the receiver.
      subject: The subject of the email message.
      msgHtml: Html message to be sent
      msgPlain: Alternative plain text message for older email clients          
      attachmentFile: The path to the file to be attached.

    Returns:
      An object containing a base64url encoded email object.
    """
    message = MIMEMultipart('mixed')
    message['to'] = to
    message['from'] = sender
    message['subject'] = subject

    messageA = MIMEMultipart('alternative')
    messageR = MIMEMultipart('related')

    messageR.attach(MIMEText(msgHtml, 'html'))
    messageA.attach(MIMEText(msgPlain, 'plain'))
    messageA.attach(messageR)

    message.attach(messageA)

    print("create_message_with_attachment: file: %s" % attachmentFile)
    content_type, encoding = mimetypes.guess_type(attachmentFile)

    if content_type is None or encoding is not None:
        content_type = 'application/octet-stream'
    main_type, sub_type = content_type.split('/', 1)
    if main_type == 'text':
        fp = open(attachmentFile, 'rb')
        msg = MIMEText(fp.read(), _subtype=sub_type)
        fp.close()
    elif main_type == 'image':
        fp = open(attachmentFile, 'rb')
        msg = MIMEImage(fp.read(), _subtype=sub_type)
        fp.close()
    elif main_type == 'audio':
        fp = open(attachmentFile, 'rb')
        msg = MIMEAudio(fp.read(), _subtype=sub_type)
        fp.close()
    else:
        fp = open(attachmentFile, 'rb')
        msg = MIMEBase(main_type, sub_type)
        msg.set_payload(fp.read())
        fp.close()
    filename = os.path.basename(attachmentFile)
    msg.add_header('Content-Disposition', 'attachment', filename=filename)
    message.attach(msg)

    return {'raw': base64.urlsafe_b64encode(message.as_string())}


def main():
    to = "to@address.com"
    sender = "from@address.com"
    subject = "subject"
    msgHtml = "Hi<br/>Html Email"
    msgPlain = "Hi\nPlain Email"
    SendMessage(sender, to, subject, msgHtml, msgPlain)
    # Send message with attachment: 
    SendMessage(sender, to, subject, msgHtml, msgPlain, '/path/to/file.pdf')

if __name__ == '__main__':
    main()

在没有浏览器的情况下在linux上运行此代码的提示:
如果您的Linux环境没有浏览器来完成第一次授权过程,您可以在笔记本电脑上运行代码(mac或windows),然后将凭据复制到目标linux机.凭证通常存储在以下目标中:

~/.credentials/gmail-python-email-send.json

Answer 2

我修改了以下内容以使用Python3,灵感来自Python Gmail API'而不是JSON serializable'

import httplib2
import os
import oauth2client
from oauth2client import client, tools
import base64
from email.mime.multipart import MIMEMultipart
from email.mime.text import MIMEText
from apiclient import errors, discovery

SCOPES = 'https://www.googleapis.com/auth/gmail.send'
CLIENT_SECRET_FILE = 'client_secret.json'
APPLICATION_NAME = 'Gmail API Python Send Email'

def get_credentials():
    home_dir = os.path.expanduser('~')
    credential_dir = os.path.join(home_dir, '.credentials')
    if not os.path.exists(credential_dir):
        os.makedirs(credential_dir)
    credential_path = os.path.join(credential_dir, 'gmail-python-email-send.json')
    store = oauth2client.file.Storage(credential_path)
    credentials = store.get()
    if not credentials or credentials.invalid:
        flow = client.flow_from_clientsecrets(CLIENT_SECRET_FILE, SCOPES)
        flow.user_agent = APPLICATION_NAME
        credentials = tools.run_flow(flow, store)
        print('Storing credentials to ' + credential_path)
    return credentials

def SendMessage(sender, to, subject, msgHtml, msgPlain):
    credentials = get_credentials()
    http = credentials.authorize(httplib2.Http())
    service = discovery.build('gmail', 'v1', http=http)
    message1 = CreateMessage(sender, to, subject, msgHtml, msgPlain)
    SendMessageInternal(service, "me", message1)

def SendMessageInternal(service, user_id, message):
    try:
        message = (service.users().messages().send(userId=user_id, body=message).execute())
        print('Message Id: %s' % message['id'])
        return message
    except errors.HttpError as error:
        print('An error occurred: %s' % error)

def CreateMessage(sender, to, subject, msgHtml, msgPlain):
    msg = MIMEMultipart('alternative')
    msg['Subject'] = subject
    msg['From'] = sender
    msg['To'] = to
    msg.attach(MIMEText(msgPlain, 'plain'))
    msg.attach(MIMEText(msgHtml, 'html'))
    raw = base64.urlsafe_b64encode(msg.as_bytes())
    raw = raw.decode()
    body = {'raw': raw}
    return body

def main():
    to = "to@address.com"
    sender = "from@address.com"
    subject = "subject"
    msgHtml = "Hi<br/>Html Email"
    msgPlain = "Hi\nPlain Email"
    SendMessage(sender, to, subject, msgHtml, msgPlain)

if __name__ == '__main__':
    main()

Answer 3

以下是发送没有(或附带)附件的电子邮件所需的Python 3.6代码(和解释).

(要附带发送只是取消注释下面的2行## without attachment并注释下面的2行## with attachment)

所有信用(和投票)到apadana

import httplib2
import os
import oauth2client
from oauth2client import client, tools
import base64
from email import encoders

#needed for attachment
import smtplib  
import mimetypes
from email import encoders
from email.message import Message
from email.mime.audio import MIMEAudio
from email.mime.base import MIMEBase
from email.mime.image import MIMEImage
from email.mime.multipart import MIMEMultipart
from email.mime.text import MIMEText
from email.mime.application import MIMEApplication
#List of all mimetype per extension: http://help.dottoro.com/lapuadlp.php  or http://mime.ritey.com/

from apiclient import errors, discovery  #needed for gmail service




## About credentials
# There are 2 types of "credentials": 
#     the one created and downloaded from https://console.developers.google.com/apis/ (let's call it the client_id) 
#     the one that will be created from the downloaded client_id (let's call it credentials, it will be store in C:\Users\user\.credentials)


        #Getting the CLIENT_ID 
            # 1) enable the api you need on https://console.developers.google.com/apis/
            # 2) download the .json file (this is the CLIENT_ID)
            # 3) save the CLIENT_ID in same folder as your script.py 
            # 4) update the CLIENT_SECRET_FILE (in the code below) with the CLIENT_ID filename


        #Optional
        # If you don't change the permission ("scope"): 
            #the CLIENT_ID could be deleted after creating the credential (after the first run)

        # If you need to change the scope:
            # you will need the CLIENT_ID each time to create a new credential that contains the new scope.
            # Set a new credentials_path for the new credential (because it's another file)
def get_credentials():
    # If needed create folder for credential
    home_dir = os.path.expanduser('~') #>> C:\Users\Me
    credential_dir = os.path.join(home_dir, '.credentials') # >>C:\Users\Me\.credentials   (it's a folder)
    if not os.path.exists(credential_dir):
        os.makedirs(credential_dir)  #create folder if doesnt exist
    credential_path = os.path.join(credential_dir, 'cred send mail.json')

    #Store the credential
    store = oauth2client.file.Storage(credential_path)
    credentials = store.get()

    if not credentials or credentials.invalid:
        CLIENT_SECRET_FILE = 'client_id to send Gmail.json'
        APPLICATION_NAME = 'Gmail API Python Send Email'
        #The scope URL for read/write access to a user's calendar data  

        SCOPES = 'https://www.googleapis.com/auth/gmail.send'

        # Create a flow object. (it assists with OAuth 2.0 steps to get user authorization + credentials)
        flow = client.flow_from_clientsecrets(CLIENT_SECRET_FILE, SCOPES)
        flow.user_agent = APPLICATION_NAME

        credentials = tools.run_flow(flow, store)

    return credentials




## Get creds, prepare message and send it
def create_message_and_send(sender, to, subject,  message_text_plain, message_text_html, attached_file):
    credentials = get_credentials()

    # Create an httplib2.Http object to handle our HTTP requests, and authorize it using credentials.authorize()
    http = httplib2.Http()

    # http is the authorized httplib2.Http() 
    http = credentials.authorize(http)        #or: http = credentials.authorize(httplib2.Http())

    service = discovery.build('gmail', 'v1', http=http)

    ## without attachment
    message_without_attachment = create_message_without_attachment(sender, to, subject, message_text_html, message_text_plain)
    send_Message_without_attachment(service, "me", message_without_attachment, message_text_plain)


    ## with attachment
    # message_with_attachment = create_Message_with_attachment(sender, to, subject, message_text_plain, message_text_html, attached_file)
    # send_Message_with_attachment(service, "me", message_with_attachment, message_text_plain,attached_file)

def create_message_without_attachment (sender, to, subject, message_text_html, message_text_plain):
    #Create message container
    message = MIMEMultipart('alternative') # needed for both plain & HTML (the MIME type is multipart/alternative)
    message['Subject'] = subject
    message['From'] = sender
    message['To'] = to

    #Create the body of the message (a plain-text and an HTML version)
    message.attach(MIMEText(message_text_plain, 'plain'))
    message.attach(MIMEText(message_text_html, 'html'))

    raw_message_no_attachment = base64.urlsafe_b64encode(message.as_bytes())
    raw_message_no_attachment = raw_message_no_attachment.decode()
    body  = {'raw': raw_message_no_attachment}
    return body



def create_Message_with_attachment(sender, to, subject, message_text_plain, message_text_html, attached_file):
    """Create a message for an email.

    message_text: The text of the email message.
    attached_file: The path to the file to be attached.

    Returns:
    An object containing a base64url encoded email object.
    """

    ##An email is composed of 3 part :
        #part 1: create the message container using a dictionary { to, from, subject }
        #part 2: attach the message_text with .attach() (could be plain and/or html)
        #part 3(optional): an attachment added with .attach() 

    ## Part 1
    message = MIMEMultipart() #when alternative: no attach, but only plain_text
    message['to'] = to
    message['from'] = sender
    message['subject'] = subject

    ## Part 2   (the message_text)
    # The order count: the first (html) will be use for email, the second will be attached (unless you comment it)
    message.attach(MIMEText(message_text_html, 'html'))
    message.attach(MIMEText(message_text_plain, 'plain'))

    ## Part 3 (attachment) 
    # # to attach a text file you containing "test" you would do:
    # # message.attach(MIMEText("test", 'plain'))

    #-----About MimeTypes:
    # It tells gmail which application it should use to read the attachment (it acts like an extension for windows).
    # If you dont provide it, you just wont be able to read the attachment (eg. a text) within gmail. You'll have to download it to read it (windows will know how to read it with it's extension). 

    #-----3.1 get MimeType of attachment
        #option 1: if you want to attach the same file just specify it’s mime types

        #option 2: if you want to attach any file use mimetypes.guess_type(attached_file) 

    my_mimetype, encoding = mimetypes.guess_type(attached_file)

    # If the extension is not recognized it will return: (None, None)
    # If it's an .mp3, it will return: (audio/mp3, None) (None is for the encoding)
    #for unrecognized extension it set my_mimetypes to  'application/octet-stream' (so it won't return None again). 
    if my_mimetype is None or encoding is not None:
        my_mimetype = 'application/octet-stream' 


    main_type, sub_type = my_mimetype.split('/', 1)# split only at the first '/'
    # if my_mimetype is audio/mp3: main_type=audio sub_type=mp3

    #-----3.2  creating the attachment
        #you don't really "attach" the file but you attach a variable that contains the "binary content" of the file you want to attach

        #option 1: use MIMEBase for all my_mimetype (cf below)  - this is the easiest one to understand
        #option 2: use the specific MIME (ex for .mp3 = MIMEAudio)   - it's a shorcut version of MIMEBase

    #this part is used to tell how the file should be read and stored (r, or rb, etc.)
    if main_type == 'text':
        print("text")
        temp = open(attached_file, 'r')  # 'rb' will send this error: 'bytes' object has no attribute 'encode'
        attachment = MIMEText(temp.read(), _subtype=sub_type)
        temp.close()

    elif main_type == 'image':
        print("image")
        temp = open(attached_file, 'rb')
        attachment = MIMEImage(temp.read(), _subtype=sub_type)
        temp.close()

    elif main_type == 'audio':
        print("audio")
        temp = open(attached_file, 'rb')
        attachment = MIMEAudio(temp.read(), _subtype=sub_type)
        temp.close()            

    elif main_type == 'application' and sub_type == 'pdf':   
        temp = open(attached_file, 'rb')
        attachment = MIMEApplication(temp.read(), _subtype=sub_type)
        temp.close()

    else:                              
        attachment = MIMEBase(main_type, sub_type)
        temp = open(attached_file, 'rb')
        attachment.set_payload(temp.read())
        temp.close()

    #-----3.3 encode the attachment, add a header and attach it to the message
    # encoders.encode_base64(attachment)  #not needed (cf. randomfigure comment)
    #https://docs.python.org/3/library/email-examples.html

    filename = os.path.basename(attached_file)
    attachment.add_header('Content-Disposition', 'attachment', filename=filename) # name preview in email
    message.attach(attachment) 


    ## Part 4 encode the message (the message should be in bytes)
    message_as_bytes = message.as_bytes() # the message should converted from string to bytes.
    message_as_base64 = base64.urlsafe_b64encode(message_as_bytes) #encode in base64 (printable letters coding)
    raw = message_as_base64.decode()  # need to JSON serializable (no idea what does it means)
    return {'raw': raw} 



def send_Message_without_attachment(service, user_id, body, message_text_plain):
    try:
        message_sent = (service.users().messages().send(userId=user_id, body=body).execute())
        message_id = message_sent['id']
        # print(attached_file)
        print (f'Message sent (without attachment) \n\n Message Id: {message_id}\n\n Message:\n\n {message_text_plain}')
        # return body
    except errors.HttpError as error:
        print (f'An error occurred: {error}')




def send_Message_with_attachment(service, user_id, message_with_attachment, message_text_plain, attached_file):
    """Send an email message.

    Args:
    service: Authorized Gmail API service instance.
    user_id: User's email address. The special value "me" can be used to indicate the authenticated user.
    message: Message to be sent.

    Returns:
    Sent Message.
    """
    try:
        message_sent = (service.users().messages().send(userId=user_id, body=message_with_attachment).execute())
        message_id = message_sent['id']
        # print(attached_file)

        # return message_sent
    except errors.HttpError as error:
        print (f'An error occurred: {error}')


def main():
    to = "youremail@gmail.com"
    sender = "myemail@gmail.com"
    subject = "subject test1"
    message_text_html  = r'Hi<br/>Html <b>hello</b>'
    message_text_plain = "Hi\nPlain Email"
    attached_file = r'C:\Users\Me\Desktop\audio.m4a'
    create_message_and_send(sender, to, subject, message_text_plain, message_text_html, attached_file)


if __name__ == '__main__':
        main()

Answer 4

更新：我最终没有使用我在下面提出的解决方案。就我而言，我必须每周左右手动获取一次刷新令牌，因为我的 OAuth“应用程序”在 Google 眼中只是一个测试应用程序或类似的东西......

\n

你应该做的，以及我最终做的也是 @miksus 下面建议的：设置应用程序密码，并将其与您之前在 SMTP 中用于旧用户名/密码身份验证的代码一起使用。请注意，这实际上是 Google 所接受的解决方案，就像 OAuth 一样，只是（至少在我的情况下）从他们的沟通中还不清楚这一点。

\n

因此，回答你的第二个问题：应用程序密码是（最简单的）推荐方式：安全，使用与以前相同（很少）的代码。我想额外的安全性来自于这样一个事实：如果有人破解了您的应用程序密码，您可以简单地撤销它并创建另一个密码。

\n

祝你好运！

\n\n

如果您想使用库，则只需要以下代码：

\n

from yagmail import SMTP\nconn = SMTP("my.email@gmail.com", oauth2_file="./credentials.json")\nconn.send(subject="It works!")\n

\n

第一次运行上述代码时，如果您还没有，则必须提供按照下面的步骤 1-4 获取的客户端 ID 和客户端密钥。

\n

笔记：首次运行必须在可以打开浏览器以完成 OAuth 授权流程的计算机上完成（因此很可能不在您的服务器上！）。

\n

代码怎么这么少？

\n

该解决方案不需要您将大量代码复制粘贴到项目中，而是委托给名为yagmail的第三方库（GitHub 上的 2.3K\xe2\xad\x90）），该库：

\n

\n
1. 实现API通信
\n
2. 启动 OAuth 授权流程，如下面的步骤 5 所示
\n

\n

据我所知，下面描述的所有步骤都是必需的，因此没有更简单的解决方案。此处描述的流程已于 2022 年 5 月进行了测试。

\n

1. 在 Google Console 中创建一个新项目

\n

在您的 Google 云控制台中，网址为https://console.cloud.google.com/

\n

\n

2. 启用GMail API

\n

\n

3. 配置 OAuth 同意屏幕

\n

\n
• 注意：您可能无法选择“内部”（我没有）。据我所知，这意味着您稍后将有一个额外的步骤，其中您将添加要用于发送到“测试人员”列表的电子邮件
\n

\n

\n

3.b. 启用“发送邮件”OAuth 范围

\n

选择“添加或删除范围”，然后启用 OAuth 范围“发送邮件”。

\n

\n

3.c. 添加您的测试用户

\n

\n
• 这是您想要发送消息的邮箱
\n
• 如果您在步骤 3 中选择“外部”，则需要此选项；如果您选择内部，可能不需要
\n

\n

\n

4. 创建一个新的OAuth客户端

\n

OAuth 客户端是您的应用程序/脚本，它将代表您使用 GMail API 发送邮件。选择“桌面应用程序”作为类型。

\n

\n

保存Client ID和Client secret- 这些可以向 Google 唯一标识您的客户端应用程序。您在下一步中将需要它们。您不必这样做，但您也可以下载包含它们的 .json 文件。

\n

\n

5. 授权客户端应用程序代表您发送电子邮件

\n

以下代码告诉 yagmail 您想要在使用 OAuth 进行身份验证时发送电子邮件：

\n

import yagmail\nyag = yagmail.SMTP("my.email@gmail.com", oauth2_file="./credentials.json")\nyag.send(subject="It works!")\n\n

\n

第一次运行此代码时，它将找不到，credentials.json因此它将：

\n

\n
1. 询问您第 4 步中的客户端 ID 和客户端密钥
\n
2. 为您提供一个链接，您可以在浏览器中打开该链接以遵循 OAuth 授权流程。在授权流程结束时，您会收到一个验证码，您可以将其粘贴回命令行中
\n

\n

完成上述操作后，credentials.json将创建文件并将其保存在进程启动的文件夹中。该文件包含授权代表您发送电子邮件所需的 OAuth 令牌。

\n

下次运行代码时，会根据 中的信息立即发送一封电子邮件credentials.json。

\n

笔记：

\n

\n
• 最后一步必须在可以打开浏览器来完成 OAuth 授权流程的计算机上完成（因此很可能不在您的服务器上！）
\n
• 获得后，credentials.json您可以将文件复制到您的服务器上
\n

\n