通过 gmail 和 python 发送电子邮件

Sending email via gmail & python

提问by apadana

What is the recommended way of sending emails with gmail and python?

使用 gmail 和 python 发送电子邮件的推荐方式是什么？

There are a lot of SO threads, but most are old and also smtp with username & password is not working any more or the user has to downgrade the security of their gmail (for example see here).

有很多 SO 线程，但大多数都是旧的，并且带有用户名和密码的 smtp 不再工作，或者用户必须降级他们的 gmail 的安全性（例如，请参见此处）。

Is OAuth the recommended way?

OAuth 是推荐的方式吗？

回答by apadana

The answer shows how to send email with gmail API and python. Also updated the answer to send emails with attachment.

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

Gmail API & OAuth-> no need to save the username and password in the script.

Gmail API & OAuth-> 无需在脚本中保存用户名和密码。

The first time the script opens a browser to authorize the script and will store credentials locally (it will not store username and password). Consequent runs won't need the browser and can send emails straight.

脚本第一次打开浏览器对脚本进行授权并将在本地存储凭据（它不会存储用户名和密码）。随后的运行不需要浏览器，可以直接发送电子邮件。

With this method you will notget errors like SMTPException below and there is no need to allow Access for less secure apps:

使用此方法，您将不会收到像下面的 SMTPException 之类的错误，并且不需要允许访问不太安全的应用程序：

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

Here are the steps to send email using gmail API:

以下是使用 gmail API 发送电子邮件的步骤：

(Wizard link here, More info here)

（向导链接在这里，更多信息在这里）

Step 2:Install the Google Client Library

第 2 步：安装 Google 客户端库

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

Step 3:Use the following script to send email(just change the variables in main function)

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 = "[email protected]"
    sender = "[email protected]"
    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()

Tip for running this code on linux, with no browser:
If your linux environment has no browser to complete the first time authorization process, you can run the code once on your laptop (mac or windows) and then copy the credentials to the destination linux machine. Credentials are normally stored in the following destination:

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首次授权过程，您可以在您的笔记本电脑（mac 或 windows）上运行一次代码，然后将凭据复制到目标 linux机器。凭据通常存储在以下目标中：

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

回答by sugarpines

I modified this as follows to work with Python3, inspired by Python Gmail API 'not JSON serializable'

我修改如下以使用 Python3，灵感来自Python Gmail API 'not 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 = "[email protected]"
    sender = "[email protected]"
    subject = "subject"
    msgHtml = "Hi<br/>Html Email"
    msgPlain = "Hi\nPlain Email"
    SendMessage(sender, to, subject, msgHtml, msgPlain)

if __name__ == '__main__':
    main()

回答by JinSnow

Here is the Python 3.6 code (and explanations) needed to send an email without (or with) an attachment.

这是发送不带（或带）附件的电子邮件所需的 Python 3.6 代码（和解释）。

(To send with attachment just uncomment the 2 lines bellow ## without attachmentand comment the 2 lines bellow ## with attachment)

（要随附件发送，只需取消注释下面的 2 行## without attachment并注释下面的 2 行## with attachment）

All the credit (and up-vote) to apadana

所有功劳（和投票）都归功于 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 = "[email protected]"
    sender = "[email protected]"
    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()

回答by Kelvin Wang

For jupyter-notebook users, after following @apadana's instructions, if you get cryptic error messages, make sure you copy the code out into it's own python file and run it using

对于 jupyter-notebook 用户，按照@apadana 的说明操作后，如果您收到神秘的错误消息，请确保将代码复制到它自己的 python 文件中并使用

%run [filename].py

(still no clue how I figured that one out)

（仍然不知道我是怎么想出来的）

when you finish doing that, you're now almost in the clear.

完成此操作后，您现在几乎清楚了。

make the last change: Gmail API Error from Code Sample - a bytes-like object is required, not 'str'

进行最后一次更改：代码示例中的 Gmail API 错误 - 需要类似字节的对象，而不是“str”

replace

代替

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

with:

和：

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

now, it should? work.

现在，应该吗？工作。

---

---

final notes: remember there are two instances of the base64 encode thingie...

最后说明：请记住有两个 base64 编码实例...

use

用

return {'raw': base64.urlsafe_b64encode(msg.as_string().encode()).decode()}

in method CreateMessageHtml

在方法 CreateMessageHtml 中

and

和

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

in method createMessageWithAttachment

在 createMessageWithAttachment 方法中

the reason you gotta do this is because the message has the variable name 'msg' in CreateMessageHtml, but name 'message' in createMessageWithAttachment. Because reasons. That's why.

你必须这样做的原因是因为消息在 CreateMessageHtml 中有变量名 'msg'，但在 createMessageWithAttachment 中有变量名 'message'。因为原因。这就是为什么。

回答by ram

thanks, @Guillame, @apadana. @Guillaume's answer worked great for me in Win/Python3.7, but with one change. For the all the 3 print statements, I had to remove the "f", as in change:

谢谢，@Guillame，@apadana。@Guillaume 的回答在 Win/Python3.7 中对我很有用，但有一个变化。对于所有 3 个打印语句，我必须删除“f”，如更改：

print (f'An error occurred: {error}')

to

到

print ('An error occurred: {error}')

Also look at the first part of @apandana's answer to get your client_secret.json file. That was more clearer for me.

另请查看@apandana 答案的第一部分以获取您的 client_secret.json 文件。这对我来说更清楚。