How to send an email through gmail without enabling 'insecure access'?

Question

Google are pushing us to improve the security of script access to their gmail smtp servers. I have no problem with that. In fact I\'m happy to help.

But they\'re n

Answer 1

I'm including some code that has been updated for python 3 usage - it seems to send emails once you get the necessary permissions and OAuth tokens working. It's mostly based off the google api website samples

    from __future__ import print_function

import base64
import os
from email.mime.text import MIMEText

import httplib2
from apiclient import discovery
from googleapiclient import errors
from oauth2client import client
from oauth2client import tools
from oauth2client.file import Storage

try:
    import argparse

    flags = argparse.ArgumentParser(parents=[tools.argparser]).parse_args()
except ImportError:
    flags = None

# If modifying these scopes, delete your previously saved credentials
# at ~/.credentials/gmail-python-quickstart.json
SCOPES = 'https://www.googleapis.com/auth/gmail.send'
CLIENT_SECRET_FILE = 'client_secret.json'
APPLICATION_NAME = 'Gmail API Python Quickstart'


def get_credentials():
    """Gets valid user credentials from storage.

    If nothing has been stored, or if the stored credentials are invalid,
    the OAuth2 flow is completed to obtain the new credentials.

    Returns:
        Credentials, the obtained credential.
    """
    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-quickstart.json')

    store = 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
        if flags:
            credentials = tools.run_flow(flow, store, flags)
        else:  # Needed only for compatibility with Python 2.6
            credentials = tools.run(flow, store)
        print('Storing credentials to ' + credential_path)
    return credentials


to = 'test@email.com'
sender = 'test@email.com'
subject = 'test emails'
message_text = 'hello this is a text test message'
user_id = 'me'

def create_message(sender, to, subject, message_text):
    """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.
      message_text: The text of the email message.

    Returns:
      An object containing a base64url encoded email object.
    """
    message = MIMEText(message_text)
    message['to'] = to
    message['from'] = sender
    message['subject'] = subject
    return {'raw': (base64.urlsafe_b64encode(message.as_bytes()).decode())}


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


def main():
    """Shows basic usage of the Gmail API.

    Creates a Gmail API service object and outputs a list of label names
    of the user's Gmail account.
    """
    credentials = get_credentials()
    http = credentials.authorize(httplib2.Http())
    service = discovery.build('gmail', 'v1', http=http)

    msg = create_message(sender,to,subject,message_text)
    message = (service.users().messages().send(userId=user_id, body=msg)
               .execute())
    print('Message Id: {}'.format(message['id']))
    results = service.users().messages().list(userId='me').execute()
    labels = results.get('labels', [])

    if not labels:
        print('No labels found.')
    else:
        print('Labels:')
        for label in labels:
            print(label['name'])


if __name__ == '__main__':
    main()