django-allauth social account connect to existing account on login

Question

I have a custom user model and I am using django-allauth for social registration and login. I am trying to connect existing user to new social account when a user login usi

Answer 1

I found the following solution here that also checks that the email addresses are verified.

from allauth.account.models import EmailAddress

def pre_social_login(self, request, sociallogin):

        # social account already exists, so this is just a login
        if sociallogin.is_existing:
            return

        # some social logins don't have an email address
        if not sociallogin.email_addresses:
            return

        # find the first verified email that we get from this sociallogin
        verified_email = None
        for email in sociallogin.email_addresses:
            if email.verified:
                verified_email = email
                break

        # no verified emails found, nothing more to do
        if not verified_email:
            return

        # check if given email address already exists as a verified email on
        # an existing user's account
        try:
            existing_email = EmailAddress.objects.get(email__iexact=email.email, verified=True)
        except EmailAddress.DoesNotExist:
            return

        # if it does, connect this new social login to the existing user
        sociallogin.connect(request, existing_email.user)

if you prefer to skip the verification step, I think this solution is still a bit better:

def pre_social_login(self, request, sociallogin):

    user = sociallogin.user
    if user.id:
        return
    if not user.email:
        return

    try:
        user = User.objects.get(email=user.email)  # if user exists, connect the account to the existing account and login
        sociallogin.connect(request, user)
    except User.DoesNotExist:
        pass

Answer 2

It's implemented out of the box with the latest allauth. You can use the following in your templates:

{% load socialaccount %}
<a href="{% provider_login_url "spotify" process="connect" %}">connect spotify account</a>

The URL is the following:

/accounts/spotify/login/?process=connect

No internal modifications needed.

Answer 3

I managed to get this working by changing the code for adapter a little bit.

adapter.py

from allauth.socialaccount.adapter import DefaultSocialAccountAdapter

class MySocialAccountAdapter(DefaultSocialAccountAdapter):
    def pre_social_login(self, request, sociallogin): 
        user = sociallogin.user
        if user.id:  
            return          
        try:
            customer = Customer.objects.get(email=user.email)  # if user exists, connect the account to the existing account and login
            sociallogin.state['process'] = 'connect'                
            perform_login(request, customer, 'none')
        except Customer.DoesNotExist:
            pass

If subclassing DefaultSocialAccountAdapter, we have to specify SOCIALACCOUNT_ADAPTER = 'myapp.my_adapter.MySocialAccountAdapter' in settings.py file