使用 python 在 Gmail 中发送邮件

Question

我正在尝试使用 Gmail API 发送一封简单的测试电子邮件，但我找到的每个代码示例都不断收到相同的错误。

我现在的代码是这样的：

def validationService():
    SCOPES = ['https://mail.google.com/']
    SERVICE_ACCOUNT_FILE = 'creds.json'
    creds = service_account.Credentials.from_service_account_file(SERVICE_ACCOUNT_FILE, scopes=SCOPES)

    service = build('gmail', 'v1', credentials=creds)
    return service


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


def CreateMessage(sender, to, subject, message_text):
  message = MIMEText(message_text)
  message['to'] = to
  message['from'] = sender
  message['subject'] = subject
  return {'raw': base64.urlsafe_b64encode(message.as_string().encode()).decode()}

service = validationService()

email = CreateMessage("sendermail@gmail.com", "receiverrmail@gmail.com", "Test", "This is a test")

sent = SendMessage(service, "sendermail@gmail.com", email)

返回

>>> An error occurred: <HttpError 400 when requesting https://www.googleapis.com/gmail/v1/users/me/messages/send?alt=json returned "Bad Request">

我也不明白 CreateMessage 中的“sender”参数和 SendMessage 中的 userId 之间的区别。

如果有目的，我使用的是服务帐户凭据

- 谢谢！

Answer 1

将service account 与Gmail API 一起使用时。您需要设置domain-wide delegation，它允许服务帐户模拟您的G Suite domain 中的任何用户。因此，您必须拥有 G Suite 帐户才能使用域范围授权，如文档所述：

如果您有 G Suite 域（例如，如果您使用 G Suite），则 G Suite 域的管理员可以授权应用程序 代表 G Suite 域中的用户访问用户数据。

那么现在，您为什么需要冒充用户（真人）？这是因为服务帐户是一个机器人（不是真人），用于服务器到服务器的交互，使您的应用程序可以调用 Google API，尽管服务帐户有一个名为 client_email 的参数，它有一个像name@project-randomnumber.iam.gserviceaccount.com 这样的结构，它不是属于真实人的真实电子邮件（我知道有点令人困惑）。

话虽如此，我对您的代码进行了一些更改。首先，我修改了您的 validationService 函数，以便使用域范围委托构建服务。

def validationService():
    # Set the crendentials 
    credentials = service_account.Credentials.\
        from_service_account_file(SERVICE_ACCOUNT_FILE, scopes= SCOPES)
    # Delegate the credentials to the user you want to impersonate
    delegated_credentials = credentials.with_subject(USER_EMAIL)
    service = discovery.build('gmail', 'v1', credentials=delegated_credentials)
    return service

在您的SendMessage 函数中不一定要传递要发送电子邮件的用户。使用 me 作为Users.messages: send Parameters 状态就足够了：

userId 字符串 用户的电子邮件地址。我的特殊价值可以是 用于表示经过身份验证的用户。

def SendMessage(service, message):
    message = service.users().messages().send(userId="me", body=message).execute()
    return message

您最后的整个代码可能如下所示：

from googleapiclient import discovery, errors
from oauth2client import file, client, tools
from google.oauth2 import service_account
from email.mime.text import MIMEText
import base64

SERVICE_ACCOUNT_FILE = 'service_account.json'
SCOPES = [' https://mail.google.com/']
# The user we want to "impersonate"
USER_EMAIL = "user@domain"


def validationService():
    # Set the crendentials 
    credentials = service_account.Credentials.\
        from_service_account_file(SERVICE_ACCOUNT_FILE, scopes= SCOPES)
    # Delegate the credentials to the user you want to impersonate
    delegated_credentials = credentials.with_subject(USER_EMAIL)
    service = discovery.build('gmail', 'v1', credentials=delegated_credentials)
    return service


def SendMessage(service, message):
    message = service.users().messages().send(userId="me", body=message).execute()
    return message


def CreateMessage(sender, to, subject, message_text):
  message = MIMEText(message_text)
  message['to'] = to
  message['from'] = sender
  message['subject'] = subject
  return {'raw': base64.urlsafe_b64encode(message.as_string().encode()).decode()}


def main():
    try:
        service = validationService()
        email = CreateMessage(USER_EMAIL, "receiverrmail@domain", "Test", "This is a test")
        email_sent = SendMessage(service, email)
        print('Message Id:', email_sent['id'])
    except errors.HttpError as err:
        print('\n---------------You have the following error-------------')
        print(err)
        print('---------------You have the following error-------------\n')


if __name__ == '__main__':
    main()

通知

您还需要通过在您的 G Suite 帐户上设置 Managing API client access 来允许您的服务帐户在使用域范围委派时访问 Google 的 API。

Answer 2

您不会伤脑筋……只需使用电子邮件和 smtplib 库即可。如果你问我，通过 Python 发送电子邮件非常简单有趣。我在下面给出了我的编码，您应该基于此开发自己的代码。如果它有效，请告诉我 - 我会很高兴。在这里……

    import email, smtplib, os, time, fnmatch
    from datetime import date, timedelta
    from email.mime.text import MIMEText
    from email.mime.image import MIMEImage
    from email.mime.multipart import MIMEMultipart

    def sendMailTo(recepient_id, today):

      login_id = 'myemailID@gmail.com'
      login_pwd = "mypassword"
      fro_ = login_id
      s_name = 'smtp.gmail.com'
      s_port = 587

      fileList = []
      fi_type = '*.pdf'
      file_path = "C:\\Myfolder\\Subfolder"

      srvr = smtplib.SMTP(s_name, s_port)
      srvr.ehlo()
      srvr.starttls()
      srvr.ehlo()
      srvr.login(login_id, login_pwd)

      sub = "Your subject here"
      # loading MIMEMultipart obj onto outer var
      outer = MIMEMultipart('alternative')
      outer["From"] = 'Your company/Personal Name'
      outer["To"] = recepient_id 
      outer['Subject'] = sub

      # storing only pdf files          
      fileList = fnmatch.filter(os.listdir(file_path), fi_type)

      for fi in fileList:
        fi_name = os.path.join(file_path, fi)
        fp = open(fi_name, 'rb')
        img = MIMEImage(fp.read(), _subtype='jpg')
        fp.close()
        img.add_header('Content-disposition', "attachment", filename = fi)
        outer.attach(img)

      #start sending email with attachment with original file name
      srvr.sendmail(fro_, recepient_id, outer.as_string())

    part = None
    outer = None
    srvr.quit()