Link/Create persons if a matching one is found for a user

Closes #332

aleksis/core/preferences.py

@@ -5,6 +5,7 @@ from django.utils.translation import gettext_lazy as _
 
 from dynamic_preferences.preferences import Section
 from dynamic_preferences.types import (
+    BooleanPreference,
     ChoicePreference,
     FilePreference,
     MultipleChoicePreference,
@@ -170,6 +171,24 @@ class PrimaryGroupField(ChoicePreference):
         return Person.syncable_fields_choices()
 
 
+@site_preferences_registry.register
+class AutoCreatePerson(BooleanPreference):
+    section = account
+    name = "auto_create_person"
+    default = False
+    required = False
+    verbose_name = _("Automatically create new persons for new users")
+
+
+@site_preferences_registry.register
+class AutoLinkPerson(BooleanPreference):
+    section = account
+    name = "auto_link_person"
+    default = False
+    required = False
+    verbose_name = _("Automatically link existing persons to new users by their e-mail address")
+
+
 @site_preferences_registry.register
 class SchoolName(StringPreference):
     section = school

aleksis/core/util/middlewares.py

@@ -2,8 +2,8 @@ from typing import Callable
 
 from django.http import HttpRequest, HttpResponse
 
-from ..models import DummyPerson
-from .core_helpers import has_person
+from ..models import DummyPerson, Person
+from .core_helpers import get_site_preferences, has_person
 
 
 class EnsurePersonMiddleware:
@@ -12,6 +12,9 @@ class EnsurePersonMiddleware:
     It is needed to inject a dummy person to a superuser that would otherwise
     not have an associated person, in order they can get their account set up
     without external help.
+
+    In addition, if configured in preferences, it auto-creates or links persons
+    to regular users if they match.
     """
 
     def __init__(self, get_response: Callable):
@@ -25,6 +28,22 @@ class EnsurePersonMiddleware:
                     first_name=request.user.first_name, last_name=request.user.last_name
                 )
                 request.user.person = dummy_person
+            else:
+                prefs = get_site_preferences()
+
+                if prefs.get("account__auto_link_person", False):
+                    person, created = Person.objects.get_or_create(
+                        email=request.user.email,
+                        defaults={
+                            "first_name": request.user.first_name,
+                            "last_name": request.user.last_name,
+                        },
+                    )
+                    if created and not prefs.get("account__auto_create_person"):
+                        return
+
+                    person.user = request.user
+                    person.save()
 
         response = self.get_response(request)
         return response