Authentication Actions

def do_auth(backend, redirect_name="next"):
    """
    Initiate authentication flow with the specified backend.
    
    This function prepares the authentication process by:
    - Saving request data and configured fields to session
    - Validating and sanitizing redirect URLs for security
    - Calling the backend's start() method to begin authentication
    
    Parameters:
    - backend: Authentication backend instance (subclass of BaseAuth)
    - redirect_name: Name of the redirect parameter in request data (default: "next")
    
    Returns:
    Backend-specific response, typically a redirect to the provider's auth URL
    or HTML content for non-redirect flows
    
    Raises:
    - AuthException: If authentication cannot be initiated
    """

from social_core.actions import do_auth
from social_core.backends.google import GoogleOAuth2

# Initialize backend with strategy and redirect URI
backend = GoogleOAuth2(strategy, redirect_uri='/auth/complete/google/')

# Start authentication - returns redirect response to Google OAuth
response = do_auth(backend, redirect_name='next')

def do_complete(backend, login, user=None, redirect_name="next", *args, **kwargs):
    """
    Complete authentication flow and return authenticated user.
    
    This function handles the provider callback by:
    - Processing partial pipeline data if present
    - Running the complete authentication pipeline
    - Calling the login function on successful authentication
    - Managing session cleanup and redirect handling
    
    Parameters:
    - backend: Authentication backend instance (subclass of BaseAuth)
    - login: Function to call for logging in the user (e.g., Django's login())
    - user: Current user instance, if any (default: None)
    - redirect_name: Name of the redirect parameter (default: "next")
    - *args: Additional arguments passed to backend.complete()
    - **kwargs: Additional keyword arguments passed to backend.complete()
    
    Returns:
    - Authenticated user instance on successful authentication
    - None if authentication failed
    - HttpResponse for redirects or partial pipeline interruptions
    
    Raises:
    - AuthException: If authentication process fails
    - Various provider-specific exceptions based on backend implementation
    """

from social_core.actions import do_complete
from social_core.backends.google import GoogleOAuth2
from django.contrib.auth import login

# In your OAuth callback view
def auth_complete_google(request):
    backend = GoogleOAuth2(strategy, redirect_uri='/auth/complete/google/')
    
    # Complete authentication and login user
    user = do_complete(
        backend=backend,
        login=login,
        user=request.user if request.user.is_authenticated else None,
        redirect_name='next',
        request=request
    )
    
    if user:
        # Authentication successful
        return redirect(request.GET.get('next', '/dashboard/'))
    else:
        # Authentication failed
        return redirect('/login/?error=auth_failed')

def do_disconnect(backend, user, association_id=None, redirect_name="next", *args, **kwargs):
    """
    Disconnect social account association from user.
    
    This function handles social account disconnection by:
    - Validating that disconnection is allowed for the user
    - Running the complete disconnection pipeline
    - Optionally revoking access tokens at the provider
    - Removing social account associations from storage
    
    Parameters:
    - backend: Authentication backend instance (subclass of BaseAuth)
    - user: User instance to disconnect social account from
    - association_id: Optional specific association ID to disconnect (default: None)
    - redirect_name: Name of the redirect parameter (default: "next")
    - *args: Additional arguments passed to disconnect pipeline
    - **kwargs: Additional keyword arguments passed to disconnect pipeline
    
    Returns:
    - Dictionary with 'url' key containing redirect URL on success
    - Dictionary with disconnect results and metadata
    
    Raises:
    - NotAllowedToDisconnect: If user cannot disconnect this account
    - AuthException: If disconnection process fails
    """

from social_core.actions import do_disconnect
from social_core.backends.google import GoogleOAuth2
from social_core.exceptions import NotAllowedToDisconnect

def disconnect_google(request):
    backend = GoogleOAuth2(strategy)
    
    try:
        result = do_disconnect(
            backend=backend,
            user=request.user,
            association_id=request.GET.get('association_id'),
            redirect_name='next'
        )
        
        if 'url' in result:
            # Redirect after successful disconnection
            return redirect(result['url'])
        else:
            # Disconnection completed
            return redirect('/profile/?message=disconnected')
            
    except NotAllowedToDisconnect:
        # User must keep at least one login method
        return redirect('/profile/?error=cannot_disconnect')

# Django example
from social_core.actions import do_auth, do_complete
from myapp.strategy import DjangoStrategy

def auth_start(request, backend_name):
    strategy = DjangoStrategy(request)
    backend = strategy.get_backend(backend_name)
    return do_auth(backend)

def auth_complete(request, backend_name):
    strategy = DjangoStrategy(request)  
    backend = strategy.get_backend(backend_name)
    return do_complete(backend, login, user=request.user)

from social_core.exceptions import AuthException, AuthCanceled

try:
    user = do_complete(backend, login, user=current_user)
except AuthCanceled:
    # User canceled authentication at provider
    return redirect('/login/?message=canceled')
except AuthException as e:
    # Other authentication errors
    return redirect(f'/login/?error={e}')