Create speaker account with SSO as part of the answer to Call for Proposals (#520)

* Make social login redirect to previous page

* Add url validate

* Add scheme check for url validation

* Resolve conversations

* Resolve conversations

* Resolve conversations

Author: HungNgien

src/pretix/control/templates/pretixcontrol/auth/login.html

@@ -55,7 +55,8 @@
             {% if login_providers %}
                 {% for provider, settings in login_providers.items %}
                     {% if settings.state %}
-                        <a href='{% url "plugins:socialauth:social.oauth.login" provider %}' data-method="post" class="btn btn-primary btn-block">
+                        <a href='{% url "plugins:socialauth:social.oauth.login" provider %}{% append_next request.GET.next %}' 
+                           data-method="post" class="btn btn-primary btn-block">
                             {% with provider|capfirst as provider_capitalized %}
                                 {% blocktrans %}Login with {{ provider_capitalized }}{% endblocktrans %}
                             {% endwith %}

src/pretix/plugins/socialauth/schemas/oauth2_params.py

@@ -0,0 +1,11 @@
+from typing import Annotated
+
+from pydantic import BaseModel, StringConstraints
+
+
+class OAuth2Params(BaseModel):
+    response_type: Annotated[str, StringConstraints(strip_whitespace=True)] = "code"
+    client_id: Annotated[str, StringConstraints(strip_whitespace=True)]
+    redirect_uri: Annotated[str, StringConstraints(strip_whitespace=True)]
+    scope: Annotated[str, StringConstraints(strip_whitespace=True)] = "profile"
+    state: Annotated[str, StringConstraints(strip_whitespace=True)]

src/pretix/plugins/socialauth/urls.py

@@ -3,7 +3,7 @@
 from . import views
 
 urlpatterns = [
-    path('oauth_login/<str:provider>/', views.oauth_login, name='social.oauth.login'),
-    path('oauth_return/', views.oauth_return, name='social.oauth.return'),
+    path('oauth_login/<str:provider>/', views.OAuthLoginView.as_view(), name='social.oauth.login'),
+    path('oauth_return/', views.OAuthReturnView.as_view(), name='social.oauth.return'),
     path('control/global/social_auth/', views.SocialLoginView.as_view(), name='admin.global.social.auth.settings')
 ]

src/pretix/plugins/socialauth/views.py

@@ -1,14 +1,16 @@
 import logging
 from enum import StrEnum
-from urllib.parse import urlencode, urljoin, urlparse, urlunparse
+from urllib.parse import parse_qs, urlencode, urljoin, urlparse, urlunparse
 
 from allauth.socialaccount.adapter import get_adapter
 from allauth.socialaccount.models import SocialApp
 from django.conf import settings
 from django.contrib import messages
+from django.http import HttpRequest, HttpResponse
 from django.shortcuts import redirect
 from django.urls import reverse
-from django.views.generic import TemplateView
+from django.utils.translation import gettext_lazy as _
+from django.views.generic import TemplateView, View
 from pydantic import ValidationError
 
 from pretix.base.models import User
@@ -18,43 +20,99 @@
 from pretix.helpers.urls import build_absolute_uri
 
 from .schemas.login_providers import LoginProviders
+from .schemas.oauth2_params import OAuth2Params
 
 logger = logging.getLogger(__name__)
 adapter = get_adapter()
 
 
-def oauth_login(request, provider):
-    gs = GlobalSettingsObject()
-    client_id = gs.settings.get('login_providers', as_type=dict).get(provider, {}).get('client_id')
-    provider = adapter.get_provider(request, provider, client_id=client_id)
-
-    base_url = provider.get_login_url(request)
-    query_params = {
-        "next": build_absolute_uri("plugins:socialauth:social.oauth.return")
-    }
-    parsed_url = urlparse(base_url)
-    updated_url = parsed_url._replace(query=urlencode(query_params))
-    return redirect(urlunparse(updated_url))
+class OAuthLoginView(View):
+    def get(self, request: HttpRequest, provider: str) -> HttpResponse:
+        self.set_oauth2_params(request)
 
+        gs = GlobalSettingsObject()
+        client_id = (
+            gs.settings.get("login_providers", as_type=dict)
+            .get(provider, {})
+            .get("client_id")
+        )
+        provider_instance = adapter.get_provider(request, provider, client_id=client_id)
+
+        base_url = provider_instance.get_login_url(request)
+        query_params = {
+            "next": build_absolute_uri("plugins:socialauth:social.oauth.return")
+        }
+        parsed_url = urlparse(base_url)
+        updated_url = parsed_url._replace(query=urlencode(query_params))
+        return redirect(urlunparse(updated_url))
+
+    @staticmethod
+    def set_oauth2_params(request: HttpRequest) -> None:
+        """
+        Handle Login with SSO button from other components
+        This function will set 'oauth2_params' in session for oauth2_callback
+        """
+        next_url = request.GET.get("next", "")
+        if not next_url:
+            return
+
+        parsed = urlparse(next_url)
+
+        # Only allow relative URLs
+        if parsed.netloc or parsed.scheme:
+            return
+
+        params = parse_qs(parsed.query)
+        sanitized_params = {
+            k: v[0]
+            for k, v in params.items()
+            if k in OAuth2Params.model_fields.keys()
+        }
+
+        try:
+            oauth2_params = OAuth2Params.model_validate(sanitized_params)
+            request.session["oauth2_params"] = oauth2_params.model_dump()
+        except ValidationError as e:
+            logger.warning("Ignore invalid OAuth2 parameters: %s.", e)
+
+
+class OAuthReturnView(View):
+    def get(self, request: HttpRequest) -> HttpResponse:
+        try:
+            user = self.get_or_create_user(request)
+            response = process_login_and_set_cookie(request, user, False)
+            oauth2_params = request.session.pop("oauth2_params", {})
+            if oauth2_params:
+                try:
+                    oauth2_params = OAuth2Params.model_validate(oauth2_params)
+                    query_string = urlencode(oauth2_params.model_dump())
+                    auth_url = reverse("control:oauth2_provider.authorize")
+                    return redirect(f"{auth_url}?{query_string}")
+                except ValidationError as e:
+                    logger.warning("Ignore invalid OAuth2 parameters: %s.", e)
+
+            return response
+        except AttributeError as e:
+            messages.error(
+                request, _("Error while authorizing: no email address available.")
+            )
+            logger.error("Error while authorizing: %s", e)
+            return redirect("control:auth.login")
 
-def oauth_return(request):
-    try:
-        user, _ = User.objects.get_or_create(
+    @staticmethod
+    def get_or_create_user(request: HttpRequest) -> User:
+        """
+        Get or create a user from social auth information.
+        """
+        return User.objects.get_or_create(
             email=request.user.email,
             defaults={
-                'locale': getattr(request, 'LANGUAGE_CODE', settings.LANGUAGE_CODE),
-                'timezone': getattr(request, 'timezone', settings.TIME_ZONE),
-                'auth_backend': 'native',
-                'password': '',
+                "locale": getattr(request, "LANGUAGE_CODE", settings.LANGUAGE_CODE),
+                "timezone": getattr(request, "timezone", settings.TIME_ZONE),
+                "auth_backend": "native",
+                "password": "",
             },
-        )
-        return process_login_and_set_cookie(request, user, False)
-    except AttributeError:
-        messages.error(
-            request, _('Error while authorizing: no email address available.')
-        )
-        logger.error('Error while authorizing: user has no email address.')
-        return redirect('control:auth.login')
+        )[0]
 
 
 class SocialLoginView(AdministratorPermissionRequiredMixin, TemplateView):