diff --git a/README.md b/README.md
index 4d249b271eca398724acb05ddd5283287a8b3dd8..cf1ca48b32027de68256c912c79d4c8fa6a81a7a 100644
--- a/README.md
+++ b/README.md
@@ -31,6 +31,9 @@ An object allowing a User to be notified of any change on a resource or a contai
| -------- | ---------- | ------- | ------------------------------------------------------------ |
| `object` | `URLField` | | ID of the resource or the container to watch |
| `inbox` | `URLField` | | ID of the inbox to notify when the resource or the container change |
+| `field` | `CharField` | | (optional) if set, then object['field'] will be sent in the notification, not object |
+
+For convenience, when you create a subscription on an object, DjangoLDP-Notification will parse the object for any one-to-many nested field relations. It will then create nested-subscriptions, i.e. a subscription on the nested field which sends an update to the same inbox, passing the parent model. If this behaviour is undesired you can delete the `Subscription` instance
# Middlewares
diff --git a/djangoldp_notification/migrations/0006_subscription_parent.py b/djangoldp_notification/migrations/0006_subscription_parent.py
new file mode 100644
index 0000000000000000000000000000000000000000..71d2447e607cd1ff3feb759513ec02729db69c33
--- /dev/null
+++ b/djangoldp_notification/migrations/0006_subscription_parent.py
@@ -0,0 +1,21 @@
+# -*- coding: utf-8 -*-
+# Generated by Django 1.11.29 on 2020-06-02 10:35
+from __future__ import unicode_literals
+
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+ dependencies = [
+ ('djangoldp_notification', '0005_auto_20200505_1733'),
+ ]
+
+ operations = [
+ migrations.AddField(
+ model_name='subscription',
+ name='parent',
+ field=models.ForeignKey(blank=True, null=True, on_delete=django.db.models.deletion.CASCADE, related_name='children', to='djangoldp_notification.Subscription'),
+ ),
+ ]
diff --git a/djangoldp_notification/migrations/0007_auto_20200604_1055.py b/djangoldp_notification/migrations/0007_auto_20200604_1055.py
new file mode 100644
index 0000000000000000000000000000000000000000..b16cee20ed3e5fd87949cf4728a8ed3422b4f1bf
--- /dev/null
+++ b/djangoldp_notification/migrations/0007_auto_20200604_1055.py
@@ -0,0 +1,24 @@
+# -*- coding: utf-8 -*-
+# Generated by Django 1.11.29 on 2020-06-04 10:55
+from __future__ import unicode_literals
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+ dependencies = [
+ ('djangoldp_notification', '0006_subscription_parent'),
+ ]
+
+ operations = [
+ migrations.RemoveField(
+ model_name='subscription',
+ name='parent',
+ ),
+ migrations.AddField(
+ model_name='subscription',
+ name='field',
+ field=models.CharField(blank=True, help_text='if set to a field name on the object model, the field will be passed instead of the object instance', max_length=255, null=True),
+ ),
+ ]
diff --git a/djangoldp_notification/models.py b/djangoldp_notification/models.py
index 6915b82e6ec0ad8aa8a46313b1b980e70a141b3b..e776a44e1cd299b0d9db219d57382b3aaa2d97b6 100644
--- a/djangoldp_notification/models.py
+++ b/djangoldp_notification/models.py
@@ -7,7 +7,7 @@ from django.db import models
from django.db.models.signals import post_save, post_delete
from django.dispatch import receiver
from django.template import loader
-from django.urls import NoReverseMatch
+from django.urls import NoReverseMatch, get_resolver
from django.utils.translation import ugettext_lazy as _
from djangoldp.fields import LDPUrlField
from djangoldp.models import Model
@@ -53,6 +53,8 @@ class Notification(Model):
class Subscription(Model):
object = models.URLField()
inbox = models.URLField()
+ field = models.CharField(max_length=255, blank=True, null=True,
+ help_text='if set to a field name on the object model, the field will be passed instead of the object instance')
def __str__(self):
return '{}'.format(self.object)
@@ -62,30 +64,42 @@ class Subscription(Model):
authenticated_perms = ["add", "view", "delete"]
permission_classes = [SubscriptionsPermissions]
- def save(self, *args, **kwargs):
- # save subscriptions for nested fields
- if self.pk is None and not self.is_backlink and self.object.startswith(settings.SITE_URL):
- try:
- # object is a WebID.. convert to local representation
- local = Model.resolve(self.object.replace(settings.SITE_URL, ''))[0]
- nested_fields = Model.get_meta(local, 'nested_fields', [])
-
- for nested_field in nested_fields:
- nested_url = str(self.object) + '1/' + nested_field + '/'
- # we have the nested_url, but we want the model contained within's container
- nested_container = Model.resolve(nested_url)[0]
+@receiver(post_save, sender=Subscription, dispatch_uid="nested_subscriber_check")
+def create_nested_subscribers(sender, instance, created, **kwargs):
+ # save subscriptions for one-to-many nested fields
+ if created and not instance.is_backlink and instance.object.startswith(settings.SITE_URL):
+ try:
+ #Â object is a WebID.. convert to local representation
+ local = Model.resolve(instance.object.replace(settings.SITE_URL, ''))[0]
+ nested_fields = Model.get_meta(local, 'nested_fields', [])
+
+ for nested_field in nested_fields:
+ try:
+ field = local._meta.get_field(nested_field)
+ nested_container = field.related_model
nested_container_url = Model.absolute_url(nested_container)
- # check a Subscription on this pair doesn't exist already
- existing_subscriptions = Subscription.objects.filter(object=nested_container_url, inbox=self.inbox)
- # save a Subscription on this container
- if not existing_subscriptions.exists():
- Subscription.objects.create(object=nested_container_url, inbox=self.inbox, is_backlink=True)
- except:
- pass
+ if field.one_to_many:
+ # get the nested view set
+ nested_url = str(instance.object) + '1/' + nested_field + '/'
+ view, args, kwargs = get_resolver().resolve(nested_url.replace(settings.SITE_URL, ''))
+ # get the reverse name for the field
+ field_name = view.initkwargs['nested_related_name']
+
+ if field_name is not None and field_name != '':
+ # check that this nested-field subscription doesn't already exist
+ existing_subscriptions = Subscription.objects.filter(object=nested_container_url, inbox=instance.inbox,
+ field=field_name)
+ # save a Subscription on this container
+ if not existing_subscriptions.exists():
+ Subscription.objects.create(object=nested_container_url, inbox=instance.inbox, is_backlink=True,
+ field=field_name)
+ except:
+ pass
+ except:
+ pass
- super(Subscription, self).save(*args, **kwargs)
# --- SUBSCRIPTION SYSTEM ---
@@ -94,6 +108,7 @@ class Subscription(Model):
def send_notification(sender, instance, **kwargs):
if sender != Notification:
threads = []
+ recipients = []
try:
url_container = settings.BASE_URL + Model.container_id(instance)
url_resource = settings.BASE_URL + Model.resource_id(instance)
@@ -102,11 +117,21 @@ def send_notification(sender, instance, **kwargs):
# dispatch a notification for every Subscription on this resource
for subscription in Subscription.objects.filter(models.Q(object=url_resource) | models.Q(object=url_container)):
- if not instance.is_backlink:
+ if not instance.is_backlink and subscription.inbox not in recipients and \
+ (not subscription.is_backlink or not kwargs.get("created")):
+ # I may have configured to send the subscription to a foreign key
+ if subscription.field is not None and len(subscription.field) > 1:
+ instance = getattr(instance, subscription.field, instance)
+ try:
+ url_resource = settings.BASE_URL + Model.resource_id(instance)
+ except NoReverseMatch:
+ continue
+
process = Thread(target=send_request, args=[subscription.inbox, url_resource, instance,
kwargs.get("created", False)])
process.start()
threads.append(process)
+ recipients.append(subscription.inbox)
def send_request(target, object_iri, instance, created):