How Django Google SSO works?¶

Current Flow¶

First, the user is redirected to the Django login page. If settings GOOGLE_SSO_ENABLED is True, the "Login with Google" button will be added to a default form.
On click, Django-Google-SSO will add, in a anonymous request session, the sso_next_url and Google Flow sso_state. This data will expire in 10 minutes (defined in GOOGLE_SSO_TIMEOUT). Then user will be redirected to Google login page.

Using Request Anonymous session

If you make any actions which change or destroy this session, like restart django, clear cookies or change browsers, ou move between localhost and 127.0.0.1, the login will fail, and you can see the message "State Mismatched. Time expired?" in the next time you log in again. Also remember the anonymous session lasts for 10 minutes, defined inGOOGLE_SSO_TIMEOUT.
On callback, Django-Google-SSO will check code and state received. If they are valid, Google's UserInfo will be retrieved. If the user is already registered in Django, the user will be logged in.
Otherwise, the user will be created and logged in, if his email domain, matches one of the GOOGLE_SSO_ALLOWABLE_DOMAINS. You can disable the auto-creation setting GOOGLE_SSO_AUTO_CREATE_USERS to False.
On creation only, this user can be set to thestaff or superuser status, if his email are in GOOGLE_SSO_STAFF_LIST or GOOGLE_SSO_SUPERUSER_LIST respectively. Please note if you add an email to one of these lists, the email domain must be added to GOOGLE_SSO_ALLOWABLE_DOMAINStoo.
This authenticated session will expire in 1 hour, or the time defined, in seconds, in GOOGLE_SSO_SESSION_COOKIE_AGE.
If login fails, you will be redirected to route defined in GOOGLE_SSO_LOGIN_FAILED_URL (default: admin:index) which will use Django Messaging system to show the error message.
If login succeeds, the user will be redirected to the next_path saved in the anonymous session, or to the route defined in GOOGLE_SSO_NEXT_URL (default: admin:index) as a fallback.

The `define_sso_providers` template tag¶

Django-Google-SSO uses this tag to define which buttons to show on the login page. This is because the same tag is used in other libraries, like django-microsoft-sso and django-github-sso. This tag checks the *_SSO_ENABLED, *_SSO_ADMIN_ENABLED and *_SSO_PAGES_ENABLED settings to return a list of enabled SSO providers for the current request.

if you need to customize this, you can pass in the request context the sso_providers variable with a list of providers to show, like this:

# views.py
from django.shortcuts import render

def my_view(request):
    ...
    sso_providers = [
        {
            "name": "Google",
            "logo_url": "...", # URL for the button logo
            "text": "...",  # Text for the button
            "login_url": "...",  # URL to redirect to start the login flow
            "css_url": "...",  # URL for the button CSS
         }
    ]
    return render(request, "my_login_template.html", {"sso_providers": sso_providers})

Also, if you're using async views, you can run the original template tags, like this:

# views.py
from django.shortcuts import render
from django_google_sso.utils import adefine_sso_providers, adefine_show_form

async def my_async_view(request):
    ...
    context = {
        "show_admin_form": await adefine_show_form(request),
        "sso_providers": await adefine_sso_providers(request)
    }
    return render(request, "my_login_template.html", context)

The same is valid for define_show_form tag

You can pass in the request context the show_admin_form variable with a boolean value to show or hide the default login form.

The setting GOOGLE_SSO_AUTHORIZATION_PROMPT controls the prompt parameter sent to Google's OpenID Connect authorization URL. It changes what Google shows to the user during authentication/consent:

"consent" (default): Always shows the consent screen, even if the user previously granted access to the requested scopes.
"select_account": Always shows the account chooser so the user can switch Google accounts before continuing.
"none": Never shows any screen. If the user is not already signed in to Google or has not granted consent yet, Google will return an error instead of showing screens.
None (or ""): Only show the relevant screens when they are needed. If the user is only logged in to one google account and that account has already consented, both the account and consent screens are bypassed. If consent hasn't been given, or the user is signed in to multiple google accounts, the relevant screens are shown. This is the default google prompt behavior.

Notes when testing locally: - If you have already granted consent to the default scopes (openid, userinfo.email, userinfo.profile) for your app, Google may only show the account selection step. This can make it seem like the experience is always the same. - To see the full consent screen again with consent, you can revoke the app permissions from your Google Account (Google Account -> Security -> Third-party access), or change the Scopes to include a new permission. - Using select_account typically results in the “Choose an account” screen, which matches what you are observing locally.

Example configuration in your Django settings:

# Valid values: "none", "consent", "select_account" and None
GOOGLE_SSO_AUTHORIZATION_PROMPT = None  # default is "consent"

For more details about prompt, see Google's documentation: https://developers.google.com/identity/openid-connect/openid-connect#prompt

How Django Google SSO works?¶

Current Flow¶

The define_sso_providers template tag¶

About the Google consent screen and the authorization prompt¶

The `define_sso_providers` template tag¶