✨(backend) add a is_first_connection flag to the User model

Backend part of #1796.

This changes allows to display an onboarding modal the first time that
the get_me() API view is called.
I originally tried to check if `User.last_login` was `None`, but it is
updated as soon as the user is logged, so I chose to create a flag on
the model.

src/backend/core/api/serializers.py

@@ -32,8 +32,21 @@ class UserSerializer(serializers.ModelSerializer):
 
     class Meta:
         model = models.User
-        fields = ["id", "email", "full_name", "short_name", "language"]
-        read_only_fields = ["id", "email", "full_name", "short_name"]
+        fields = [
+            "id",
+            "email",
+            "full_name",
+            "short_name",
+            "language",
+            "is_first_connection",
+        ]
+        read_only_fields = [
+            "id",
+            "email",
+            "full_name",
+            "short_name",
+            "is_first_connection",
+        ]
 
     def get_full_name(self, instance):
         """Return the full name of the user."""

src/backend/core/api/viewsets.py

@@ -318,6 +318,25 @@ class UserViewSet(
             self.serializer_class(request.user, context=context).data
         )
 
+    @drf.decorators.action(
+        detail=False,
+        methods=["post"],
+        url_path="onboarding-done",
+        permission_classes=[permissions.IsAuthenticated],
+    )
+    def onboarding_done(self, request):
+        """
+        Allows the frontend to mark the first connection as done for the current user,
+        e.g. after showing an onboarding message.
+        """
+        if request.user.is_first_connection:
+            request.user.is_first_connection = False
+            request.user.save(update_fields=["is_first_connection", "updated_at"])
+
+        return drf.response.Response(
+            {"detail": "Onboarding marked as done."}, status=status.HTTP_200_OK
+        )
+
 
 class ReconciliationConfirmView(APIView):
     """API endpoint to confirm user reconciliation emails.
@@ -2224,6 +2243,7 @@ class DocumentAccessViewSet(
         "user__full_name",
         "user__email",
         "user__language",
+        "user__is_first_connection",
         "document__id",
         "document__path",
         "document__depth",

src/backend/core/migrations/0030_user_is_first_connection.py

@@ -0,0 +1,32 @@
+# Generated by Django 5.2.11 on 2026-03-04 14:49
+
+from django.db import migrations, models
+
+
+def set_is_first_connection_false(apps, schema_editor):
+    """Update all existing user.is_first_connection to False."""
+    user = apps.get_model("core", "User")
+
+    user.objects.update(is_first_connection=False)
+
+
+class Migration(migrations.Migration):
+    dependencies = [
+        ("core", "0029_userreconciliationcsvimport_userreconciliation"),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name="user",
+            name="is_first_connection",
+            field=models.BooleanField(
+                default=True,
+                help_text="Whether the user has completed the first connection process.",
+                verbose_name="first connection status",
+            ),
+        ),
+        migrations.RunPython(
+            set_is_first_connection_false,
+            reverse_code=migrations.RunPython.noop,
+        ),
+    ]

src/backend/core/models.py

@@ -193,6 +193,11 @@ class User(AbstractBaseUser, BaseModel, auth_models.PermissionsMixin):
             "Unselect this instead of deleting accounts."
         ),
     )
+    is_first_connection = models.BooleanField(
+        _("first connection status"),
+        default=True,
+        help_text=_("Whether the user has completed the first connection process."),
+    )
 
     objects = UserManager()
 

src/backend/core/tests/documents/test_api_document_accesses.py

@@ -245,15 +245,18 @@ def test_api_document_accesses_list_authenticated_related_privileged(
                     "path": access.document.path,
                     "depth": access.document.depth,
                 },
-                "user": {
-                    "id": str(access.user.id),
-                    "email": access.user.email,
-                    "language": access.user.language,
-                    "full_name": access.user.full_name,
-                    "short_name": access.user.short_name,
-                }
-                if access.user
-                else None,
+                "user": (
+                    {
+                        "id": str(access.user.id),
+                        "email": access.user.email,
+                        "language": access.user.language,
+                        "full_name": access.user.full_name,
+                        "short_name": access.user.short_name,
+                        "is_first_connection": access.user.is_first_connection,
+                    }
+                    if access.user
+                    else None
+                ),
                 "max_ancestors_role": None,
                 "max_role": access.role,
                 "team": access.team,

src/backend/core/tests/migrations/test_migrations_0018_update_blank_title.py

@@ -1,7 +1,5 @@
 import pytest
 
-from core import models
-
 
 @pytest.mark.django_db
 def test_update_blank_title_migration(migrator):

src/backend/core/tests/migrations/test_migrations_0020_remove_is_public_add_field_attachments_and_duplicated_from.py

@@ -7,8 +7,6 @@ from django.core.files.storage import default_storage
 import pycrdt
 import pytest
 
-from core import models
-
 
 @pytest.mark.django_db
 def test_populate_attachments_on_all_documents(migrator):

src/backend/core/tests/migrations/test_migrations_0030_user_is_first_connection.py

@@ -0,0 +1,52 @@
+"""Module testing migration 0030 about adding is_first_connection to user model."""
+
+from django.contrib.auth.hashers import make_password
+
+import factory
+import pytest
+
+from core import models
+
+
+@pytest.mark.django_db
+def test_set_is_first_connection_false(migrator):
+    """
+    Test that once the migration adding is_first_connection column to user model is applied
+    all existing user have the False value.
+    """
+    old_state = migrator.apply_initial_migration(
+        ("core", "0029_userreconciliationcsvimport_userreconciliation")
+    )
+    OldUser = old_state.apps.get_model("core", "User")
+
+    old_user1 = OldUser.objects.create(
+        email="[email protected]", sub="user1", password=make_password("password")
+    )
+    old_user2 = OldUser.objects.create(
+        email="[email protected]", sub="user2", password=make_password("password")
+    )
+
+    assert hasattr(old_user1, "is_first_connection") is False
+    assert hasattr(old_user2, "is_first_connection") is False
+
+    # # Apply the migration
+    new_state = migrator.apply_tested_migration(
+        ("core", "0030_user_is_first_connection")
+    )
+
+    NewUser = new_state.apps.get_model("core", "User")
+
+    updated_user1 = NewUser.objects.get(id=old_user1.id)
+
+    assert updated_user1.is_first_connection is False
+
+    updated_user2 = NewUser.objects.get(id=old_user2.id)
+
+    assert updated_user2.is_first_connection is False
+
+    # create a new user after migration
+
+    new_user1 = NewUser.objects.create(
+        email="email3example.com", sub="user3", password=make_password("password")
+    )
+    assert new_user1.is_first_connection is True

src/backend/core/tests/test_api_users.py

@@ -460,6 +460,7 @@ def test_api_users_retrieve_me_authenticated():
         "full_name": user.full_name,
         "language": user.language,
         "short_name": user.short_name,
+        "is_first_connection": True,
     }
 
 
@@ -489,9 +490,37 @@ def test_api_users_retrieve_me_authenticated_empty_name():
         "full_name": "test_foo",
         "language": user.language,
         "short_name": "test_foo",
+        "is_first_connection": True,
     }
 
 
+def test_api_users_retrieve_me_onboarding():
+    """
+    On first connection of a new user, the "is_first_connection" flag should be True.
+
+    The frontend can use this flag to trigger specific behavior for first time users,
+    e.g. showing an onboarding message, and update the flag to False after onboarding is done.
+    """
+    user = factories.UserFactory()
+
+    client = APIClient()
+    client.force_login(user)
+
+    # First request: flag should be True
+    first_response = client.get("/api/v1.0/users/me/")
+    assert first_response.status_code == 200
+    assert first_response.json()["is_first_connection"] is True
+
+    update_response = client.post("/api/v1.0/users/onboarding-done/")
+
+    assert update_response.status_code == 200
+
+    # Second request: flag should be False
+    second_response = client.get("/api/v1.0/users/me/")
+    assert second_response.status_code == 200
+    assert second_response.json()["is_first_connection"] is False
+
+
 def test_api_users_retrieve_anonymous():
     """Anonymous users should not be allowed to retrieve a user."""
     client = APIClient()