🗃️(teams) add Team dependencies as a tree

This provides the technical way to create Team trees.
The implementation is quite naive.

src/backend/core/factories.py

@@ -189,7 +189,6 @@ class TeamFactory(factory.django.DjangoModelFactory):
 
     class Meta:
         model = models.Team
-        django_get_or_create = ("name",)
         skip_postgeneration_save = True
 
     name = factory.Sequence(lambda n: f"team{n}")

src/backend/core/migrations/0009_team_depth_team_numchild_team_path_and_more.py

@@ -0,0 +1,53 @@
+# Generated by Django 5.1.3 on 2024-11-26 13:55
+
+from django.db import migrations, models
+
+from treebeard.mp_tree import MP_Node
+
+
+def update_team_paths(apps, schema_editor):
+    Team = apps.get_model("core", "Team")
+    alphabet = MP_Node.alphabet
+    steplen = MP_Node.steplen
+
+    # for default values, this resolves to: "{:04d}"
+    path_format = f"{{:{alphabet[0]}{steplen}d}}"
+
+    nodes = Team.objects.all().order_by("created_at")
+    for i, node in enumerate(nodes, 1):
+        node.path = path_format.format(i)
+
+    if nodes:
+        Team.objects.bulk_update(nodes, ["path"])
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('core', '0008_change_user_profile_to_contact'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='team',
+            name='depth',
+            field=models.PositiveIntegerField(default=0),
+            preserve_default=False,
+        ),
+        migrations.AddField(
+            model_name='team',
+            name='numchild',
+            field=models.PositiveIntegerField(default=0),
+        ),
+        migrations.AddField(
+            model_name='team',
+            name='path',
+            field=models.CharField(default='', max_length=255),
+            preserve_default=False,
+        ),
+        migrations.RunPython(update_team_paths, migrations.RunPython.noop),
+        migrations.AlterField(
+            model_name="team",
+            name="path",
+            field=models.CharField(max_length=255, unique=True),
+        ),
+    ]

src/backend/core/models.py

@@ -27,6 +27,7 @@
 
 import jsonschema
 from timezone_field import TimeZoneField
+from treebeard.mp_tree import MP_Node, MP_NodeManager
 
 from core.enums import WebhookStatusChoices
 from core.utils.webhooks import scim_synchronizer
@@ -602,7 +603,34 @@ def __str__(self):
         return f"{self.user!s} is {self.role:s} in organization {self.organization!s}"
 
 
-class Team(BaseModel):
+class TeamManager(MP_NodeManager):
+    """
+    Custom manager for the Team model, to manage complexity/automation.
+    """
+
+    def create(self, parent_id=None, **kwargs):
+        """
+        Replace the default create method to ease the Team creation process.
+
+        Notes:
+            - the `add_*` methods from django-treebeard does not support the "using db".
+              Which means it will always use the default db.
+            - the `add_*` methods from django-treebeard does not support the "force_insert".
+
+        """
+        if parent_id is None:
+            return self.model.add_root(**kwargs)
+
+        # Retrieve parent object, because django-treebeard uses raw queries for most
+        # write operations, and raw queries don’t update the django objects of the db
+        # entries they modify. See caveats in the django-treebeard documentation.
+        # This might be changed later if we never do any operation on the parent object
+        # before creating the child.
+        # Beware the N+1 here.
+        return self.get(pk=parent_id).add_child(**kwargs)
+
+
+class Team(MP_Node, BaseModel):
     """
     Represents the link between teams and users, specifying the role a user has in a team.
 
@@ -633,6 +661,8 @@ class Team(BaseModel):
         blank=True,
     )
 
+    objects = TeamManager()
+
     class Meta:
         db_table = "people_team"
         ordering = ("name",)

src/backend/core/tests/test_models_teams.py

@@ -134,3 +134,67 @@ def test_models_teams_get_abilities_preset_role(django_assert_num_queries):
         "put": False,
         "manage_accesses": False,
     }
+
+
+# test trees
+
+def test_models_teams_create_root_team():
+    """Create a root team."""
+    team = models.Team.add_root(name="Root Team")
+    assert team.is_root()
+    assert team.name == "Root Team"
+
+
+def test_models_teams_create_child_team():
+    """Create a child team."""
+    root_team = models.Team.add_root(name="Root Team")
+    child_team = root_team.add_child(name="Child Team")
+    assert child_team.is_child_of(root_team)
+    assert child_team.name == "Child Team"
+    assert child_team.get_parent() == root_team
+
+
+def test_models_teams_create_grandchild_team():
+    """Create a grandchild team."""
+    root_team = models.Team.add_root(name="Root Team")
+    child_team = root_team.add_child(name="Child Team")
+    grandchild_team = child_team.add_child(name="Grandchild Team")
+    assert grandchild_team.is_child_of(child_team)
+    assert grandchild_team.name == "Grandchild Team"
+    assert grandchild_team.get_parent() == child_team
+
+
+def test_models_teams_move_team():
+    """Move a team to another parent."""
+    root_team = models.Team.add_root(name="Root Team")
+    child_team = root_team.add_child(name="Child Team")
+    new_root_team = models.Team.add_root(name="New Root Team")
+    child_team.move(new_root_team, pos="first-child")
+    child_team.refresh_from_db()
+    assert child_team.get_parent(update=True) == new_root_team
+
+
+def test_models_teams_delete_team():
+    """
+    Delete a parent team also deletes children.
+
+    This might not be what we want, but it's the default behavior of treebeard.
+    """
+    root_team = models.Team.add_root(name="Root Team")
+    root_team.add_child(name="Child Team")
+
+    assert models.Team.objects.all().count() == 2
+    root_team.delete()
+
+    assert models.Team.objects.all().count() == 0
+
+
+def test_models_teams_manager_create():
+    """Create a team using the manager."""
+    team = models.Team.objects.create(name="Team")
+    assert team.is_root()
+    assert team.name == "Team"
+
+    child_team = models.Team.objects.create(name="Child Team", parent_id=team.pk)
+    assert child_team.is_child_of(team)
+    assert child_team.name == "Child Team"

src/backend/demo/management/commands/create_demo.py

@@ -13,6 +13,7 @@
 from django.utils.text import slugify
 
 from faker import Faker
+from treebeard.mp_tree import MP_Node
 
 from core import models
 
@@ -45,7 +46,29 @@ def _bulk_create(self, objects):
         if not objects:
             return
 
-        objects[0]._meta.model.objects.bulk_create(objects, ignore_conflicts=False)  # noqa: SLF001
+        objects_model = objects[0]._meta.model  # noqa: SLF001
+        if issubclass(objects_model, MP_Node):
+            # For treebeard models, we need to create the tree structure
+            # in a specific way. This is not perfect but it works for the
+            # current use case.
+            model_fields = objects_model._meta.concrete_fields  # noqa: SLF001
+            bulk_data = [
+                {
+                    "data": {
+                        field.name: field.value_from_object(obj)
+                        for field in model_fields
+                        if field.value_from_object(obj)
+                    }
+                }
+                for obj in objects
+            ]
+            objects_model.load_bulk(bulk_data)
+        else:
+            objects_model.objects.bulk_create(
+                objects,
+                ignore_conflicts=False,
+            )
+
         # In debug mode, Django keeps query cache which creates a memory leak in this case
         db.reset_queries()
         self.queue[objects[0]._meta.model.__name__] = []  # noqa: SLF001

src/backend/people/settings.py

@@ -215,6 +215,7 @@ class Base(Configuration):
         "dockerflow.django",
         "rest_framework",
         "parler",
+        "treebeard",
         "easy_thumbnails",
         # Django
         "django.contrib.auth",

src/backend/pyproject.toml

@@ -32,6 +32,7 @@ dependencies = [
     "django-cors-headers==4.6.0",
     "django-countries==7.6.1",
     "django-parler==2.3",
+    "django-treebeard==4.7.1",
     "redis==5.2.0",
     "django-redis==5.4.0",
     "django-storages==1.14.4",