feat: multi tenancy support

app/apps/common/admin.py

@@ -0,0 +1,7 @@
+from django.contrib import admin
+
+
+class SharedObjectModelAdmin(admin.ModelAdmin):
+    def get_queryset(self, request):
+        # Use the all_objects manager to show all transactions, including deleted ones
+        return self.model.all_objects.all()

app/apps/common/fields/forms/dynamic_select.py

@@ -4,6 +4,7 @@ from django.db import transaction
 from django.utils.translation import gettext_lazy as _
 
 from apps.common.widgets.tom_select import TomSelect, TomSelectMultiple
+from apps.common.middleware.thread_local import get_current_user
 
 
 class DynamicModelChoiceField(forms.ModelChoiceField):
@@ -55,19 +56,24 @@ class DynamicModelChoiceField(forms.ModelChoiceField):
                 if self.create_field:
                     try:
                         with transaction.atomic():
-                            instance, _ = self.model.objects.update_or_create(
-                                **{self.create_field: value}
-                            )
+                            # First try to get the object
+                            lookup = {self.create_field: value}
+                            try:
+                                instance = self.model.objects.get(**lookup)
+                            except self.model.DoesNotExist:
+                                # Create a new instance directly
+                                instance = self.model(**lookup)
+                                instance.save()
+
                             self._created_instance = instance
                             return instance
                     except Exception as e:
-                        raise ValidationError(
-                            self.error_messages["invalid_choice"], code="invalid_choice"
-                        )
+                        raise ValidationError(_("Error creating new instance"))
                 else:
                     raise ValidationError(
                         self.error_messages["invalid_choice"], code="invalid_choice"
                     )
+
         return super().clean(value)
 
     def bound_data(self, data, initial):
@@ -90,8 +96,6 @@ class DynamicModelMultipleChoiceField(forms.ModelMultipleChoiceField):
 
     def __init__(self, model, **kwargs):
         """
-        Initialize the CreateIfNotExistsModelMultipleChoiceField.
-
         Args:
             create_field (str): The name of the field to use when creating new instances.
             *args: Variable length argument list.
@@ -123,33 +127,28 @@ class DynamicModelMultipleChoiceField(forms.ModelMultipleChoiceField):
         """
         try:
             with transaction.atomic():
-                instance, _ = self.model.objects.update_or_create(
-                    **{self.create_field: value}
-                )
-            return instance
+                # Check if exists first without using update_or_create
+                lookup = {self.create_field: value}
+                try:
+                    # Use base manager to bypass distinct filters
+                    instance = self.model.objects.get(**lookup)
+                    return instance
+                except self.model.DoesNotExist:
+                    # Create a new instance directly
+                    instance = self.model(**lookup)
+                    instance.save()
+                    return instance
         except Exception as e:
+            print(e)
             raise ValidationError(_("Error creating new instance"))
 
     def clean(self, value):
-        """
-        Clean and validate the field value.
-
-        This method checks if each selected choice exists in the database.
-        If a choice doesn't exist, it creates a new instance of the model.
-
-        Args:
-            value (list): List of selected values.
-
-        Returns:
-            list: A list containing all selected and newly created model instances.
-
-        Raises:
-            ValidationError: If there's an error during the cleaning process.
-        """
         if not value:
             return []
 
         string_values = set(str(v) for v in value)
+
+        # Get existing objects first
         existing_objects = list(
             self.queryset.filter(**{f"{self.create_field}__in": string_values})
         )
@@ -157,13 +156,11 @@ class DynamicModelMultipleChoiceField(forms.ModelMultipleChoiceField):
             str(getattr(obj, self.create_field)) for obj in existing_objects
         )
 
+        # Create new objects for missing values
         new_values = string_values - existing_values
         new_objects = []
 
         for new_value in new_values:
-            try:
-                new_objects.append(self._create_new_instance(new_value))
-            except ValidationError as e:
-                raise ValidationError(_("Error creating new instance"))
+            new_objects.append(self._create_new_instance(new_value))
 
         return existing_objects + new_objects

app/apps/common/forms.py

@@ -0,0 +1,95 @@
+from crispy_forms.bootstrap import FormActions
+from django import forms
+from django.contrib.auth import get_user_model
+from django.utils.translation import gettext_lazy as _
+from crispy_forms.helper import FormHelper
+from crispy_forms.layout import Layout, Field, Submit, Div, HTML
+
+from apps.common.widgets.tom_select import TomSelect, TomSelectMultiple
+from apps.common.models import SharedObject
+from apps.common.widgets.crispy.submit import NoClassSubmit
+
+User = get_user_model()
+
+
+class SharedObjectForm(forms.Form):
+    """
+    Generic form for editing visibility and sharing settings
+    for models inheriting from SharedObject.
+    """
+
+    owner = forms.ModelChoiceField(
+        queryset=User.objects.all(),
+        required=False,
+        label=_("Owner"),
+        widget=TomSelect(clear_button=False),
+        help_text=_(
+            "The owner of this object, if empty all users can see, edit and take ownership."
+        ),
+    )
+    shared_with_users = forms.ModelMultipleChoiceField(
+        queryset=User.objects.all(),
+        required=False,
+        widget=TomSelectMultiple(clear_button=True),
+        label=_("Shared with users"),
+        help_text=_("Select users to share this object with"),
+    )
+    visibility = forms.ChoiceField(
+        choices=SharedObject.Visibility.choices,
+        required=True,
+        label=_("Visibility"),
+        help_text=_(
+            "Private: Only shown for the owner and shared users. Only editable by the owner."
+            "<br/>"
+            "Public: Shown for all users. Only editable by the owner."
+        ),
+    )
+
+    class Meta:
+        fields = ["visibility", "shared_with_users"]
+        widgets = {
+            "visibility": TomSelect(clear_button=False),
+        }
+
+    def __init__(self, *args, **kwargs):
+        # Get the current user to filter available sharing options
+        self.user = kwargs.pop("user", None)
+        self.instance = kwargs.pop("instance", None)
+
+        super().__init__(*args, **kwargs)
+
+        # Pre-populate shared users if instance exists
+        if self.instance:
+            self.fields["shared_with_users"].initial = self.instance.shared_with.all()
+            self.fields["visibility"].initial = self.instance.visibility
+            self.fields["owner"].initial = self.instance.owner
+
+        # Set up crispy form helper
+        self.helper = FormHelper()
+        self.helper.form_method = "post"
+        self.helper.form_tag = False
+
+        self.helper.layout = Layout(
+            Field("owner"),
+            Field("visibility"),
+            HTML("<hr>"),
+            Field("shared_with_users"),
+            FormActions(
+                NoClassSubmit(
+                    "submit", _("Save"), css_class="btn btn-outline-primary w-100"
+                ),
+            ),
+        )
+
+    def save(self):
+        instance = self.instance
+
+        instance.visibility = self.cleaned_data["visibility"]
+        instance.owner = self.cleaned_data["owner"]
+
+        instance.save()
+
+        # Clear and set shared_with users
+        instance.shared_with.set(self.cleaned_data.get("shared_with_users", []))
+
+        return instance

app/apps/common/middleware/thread_local.py

@@ -56,6 +56,16 @@ def get_current_user():
     if request:
         return getattr(request, "user", None)
 
+    return getattr(_thread_locals, "user", None)
+
+
+def write_current_user(user):
+    _thread_locals.user = user
+
+
+def delete_current_user():
+    del _thread_locals.user
+
 
 class ThreadLocalMiddleware(MiddlewareMixin):
     """Simple middleware that adds the request object in thread local storage."""

app/apps/common/models.py

@@ -0,0 +1,84 @@
+from django.db import models
+from django.conf import settings
+from django.db.models import Q
+from django.utils.translation import gettext_lazy as _
+
+from apps.common.middleware.thread_local import get_current_user
+
+
+class SharedObjectManager(models.Manager):
+    def get_queryset(self):
+        """Return only objects the user can access"""
+        user = get_current_user()
+        base_qs = super().get_queryset()
+
+        if user and user.is_authenticated:
+            return base_qs.filter(
+                Q(visibility="public")
+                | Q(owner=user)
+                | Q(shared_with=user)
+                | Q(visibility="private", owner=None)
+            ).distinct()
+
+        return base_qs.filter(visibility="public")
+
+
+class SharedObject(models.Model):
+    # Access control enum
+    class Visibility(models.TextChoices):
+        private = "private", _("Private")
+        is_paid = "public", _("Public")
+
+    # Core sharing fields
+    owner = models.ForeignKey(
+        settings.AUTH_USER_MODEL,
+        on_delete=models.CASCADE,
+        related_name="%(class)s_owned",
+        null=True,
+        blank=True,
+    )
+    visibility = models.CharField(
+        max_length=10, choices=Visibility.choices, default=Visibility.private
+    )
+    shared_with = models.ManyToManyField(
+        settings.AUTH_USER_MODEL, related_name="%(class)s_shared", blank=True
+    )
+
+    # Use as abstract base class
+    class Meta:
+        abstract = True
+        indexes = [
+            models.Index(fields=["visibility"]),
+        ]
+
+    def is_accessible_by(self, user):
+        """Check if a user can access this object"""
+        return (
+            self.visibility == "public"
+            or self.owner == user
+            or (self.visibility == "shared" and user in self.shared_with.all())
+        )
+
+    def save(self, *args, **kwargs):
+        if not self.pk and not self.owner:
+            self.owner = get_current_user()
+        super().save(*args, **kwargs)
+
+
+class OwnedObject(models.Model):
+    owner = models.ForeignKey(
+        settings.AUTH_USER_MODEL,
+        on_delete=models.CASCADE,
+        related_name="%(class)s_owned",
+        null=True,
+        blank=True,
+    )
+
+    # Use as abstract base class
+    class Meta:
+        abstract = True
+
+    def save(self, *args, **kwargs):
+        if not self.pk and not self.owner:
+            self.owner = get_current_user()
+        super().save(*args, **kwargs)