update-gmail-signature

import os
import pickle
from googleapiclient.discovery import build
from google_auth_oauthlib.flow import InstalledAppFlow
from google.auth.transport.requests import Request
from google.oauth2 import service_account

# While modifying these SCOPES, delete the file token.pickle.
SCOPES = ['https://www.googleapis.com/auth/gmail.settings.basic']

def get_credentials(user_email, service_account_mode=False):
    """
    Get the Google API credentials.
    If service_account_mode is enabled, it will use service account credentials.
    Otherwise, it will use the credentials from 'token.pickle' or run an OAuth2 flow.
    """
    if service_account_mode:
        # Set path to the Service Account Key file
        SERVICE_ACCOUNT_FILE = 'path/to/service-account-file.json'

        # Create a credentials object using the service account file and the specified scopes
        credentials = service_account.Credentials.from_service_account_file(
            SERVICE_ACCOUNT_FILE, scopes=SCOPES)

        # Use the credentials object to create a delegated credentials object
        delegated_credentials = credentials.with_subject(user_email)

        return delegated_credentials
    else:
        # Load client ID and client secret from a local file
        creds = None
        if os.path.exists('token.pickle'):
            with open('token.pickle', 'rb') as token:
                creds = pickle.load(token)
        
        # If there are no (valid) credentials available, let the user log in
        if not creds or not creds.valid:
            if creds and creds.expired and creds.refresh_token:
                creds.refresh(Request())
            else:
                flow = InstalledAppFlow.from_client_secrets_file(
                    'path/to/client_secret.json', SCOPES)
                creds = flow.run_local_server(port=0)
        
            # Save the credentials for the next run
            with open('token.pickle', 'wb') as token:
                pickle.dump(creds, token)

        return creds


def update_signature(user_email, signature):
    """
    Updates the user's Gmail signature.
    
    Args:
        user_email: the email address of the user.
        signature: the new Gmail signature.
    """
    service_account_mode = False if '@gmail.com' in user_email else True

    creds = get_credentials(user_email, service_account_mode)

    # Create a service object for the Gmail API
    service = build('gmail', 'v1', credentials=creds)
    
    
    

    # Update the signature of the user's primary email
    body = {
        'signature': signature
    }
    addresses = service.users().settings().sendAs().list(userId='me').execute().get('sendAs')
    for address in addresses:
        # Update the signature of the primary address
        if address.get('isPrimary'):
            body = {'signature': signature}
            service.users().settings().sendAs().patch(userId='me', sendAsEmail=address['sendAsEmail'], body=body).execute()
    # service.users().settings().sendAs().patch(userId=user_email, sendAsEmail=user_email, body=body).execute()

    # If it's not a service account, check for aliases
    if not service_account_mode:
        # Get the list of aliases for the user
        results = service.users().settings().sendAs().list(userId=user_email).execute()
        aliases = results.get('sendAs', [])

        # Update the signatures of the aliases, if the user wants to
        for alias in aliases:
            if alias['sendAsEmail'] != user_email:
                response = input(f'Do you want to update the signature of {alias["sendAsEmail"]}? (yes/no) ')
                if response.lower() == 'yes':
                    alias_signature = input(f'Enter the new signature for {alias["sendAsEmail"]}: ')
                    body = {
                        'signature': alias_signature
                    }
                    service.users().settings().sendAs().patch(userId=user_email, sendAsEmail=alias['sendAsEmail'], body=body).execute()



# Update the signature of a non-service account user
#update_signature('your-email@gmail.com', '<b>Your new signature</b>')

# Update the signature of a service account user
#update_signature('user@your-domain.com', '<b>Your new signature</b>', service_account_mode=True)

email = 'example@gmail.com'  # Replace with the actual email
signature = '<b>Your new signature</b>'

if "@gmail.com" in email:
    update_signature(email, signature, service_account_mode=False)
else:
    update_signature(email, signature, service_account_mode=True)