[models] Added automatic removal of old nodes #46

README.rst

@@ -13,7 +13,7 @@ django-netjsongraph
 
 .. image:: https://badge.fury.io/py/django-netjsongraph.svg
    :target: http://badge.fury.io/py/django-netjsongraph
-   
+
 .. image:: https://img.shields.io/gitter/room/nwjs/nw.js.svg?style=flat-square
    :target: https://gitter.im/openwisp/general
 
@@ -276,6 +276,20 @@ Setting this to ``False`` will disable this feature.
 Path of the visualizer css file. Allows customization of css according to user's
 preferences.
 
+``NETJSONGRAPH_NODE_EXPIRATION``
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
++--------------+--------------------------------+
+| **type**:    | ``int``                        |
++--------------+--------------------------------+
+| **default**: | ``False``                      |
++--------------+--------------------------------+
+
+If a node has not been modified since the days specified and if it has no links,
+it will be deleted by the ``update_topology`` management command. This depends on
+``NETJSONGRAPH_LINK_EXPIRATION`` being enabled.
+Replace ``False`` with an integer to enable the feature.
+
 Overriding visualizer templates
 -------------------------------
 

django_netjsongraph/base/node.py

@@ -1,12 +1,16 @@
 import json
 from collections import OrderedDict
+from datetime import timedelta
 
 from django.db import models
 from django.utils.encoding import python_2_unicode_compatible
 from django.utils.functional import cached_property
+from django.utils.timezone import now
 from jsonfield import JSONField
 from rest_framework.utils.encoders import JSONEncoder
 
+from .. import settings
+from ..utils import print_info
 from .base import TimeStampedEditableModel
 
 
@@ -122,3 +126,22 @@ def count_address(cls, address, topology):
         address = '{0};'.format(address)
         return cls.objects.filter(topology=topology,
                                   addresses__contains=address).count()
+
+    @classmethod
+    def delete_expired_nodes(cls):
+        """
+        deletes nodes that have not been  connected to the network
+        for more than ``NETJSONGRAPH__EXPIRATION`` days
+        """
+        NODE_EXPIRATION = settings.NODE_EXPIRATION
+        LINK_EXPIRATION = settings.LINK_EXPIRATION
+        if NODE_EXPIRATION not in [False, None] and LINK_EXPIRATION not in [False, None]:
+            expiration_date = now() - timedelta(days=int(NODE_EXPIRATION))
+            expired_nodes = cls.objects.filter(modified__lt=expiration_date,
+                                               source_link_set__isnull=True,
+                                               target_link_set__isnull=True)
+            expired_nodes_length = len(expired_nodes)
+            if expired_nodes_length:
+                print_info('Deleting {0} expired nodes'.format(expired_nodes_length))
+                for node in expired_nodes:
+                    node.delete()

django_netjsongraph/base/topology.py

@@ -323,6 +323,7 @@ def update_all(cls, label=None):
             with log_failure('update', topology):
                 topology.update()
         cls().link_model.delete_expired_links()
+        cls().node_model.delete_expired_nodes()
 
     @classmethod
     def save_snapshot_all(cls, label=None):

django_netjsongraph/settings.py

@@ -13,4 +13,5 @@
 SIGNALS = getattr(settings, 'NETJSONGRAPH_SIGNALS', None)
 TIMEOUT = getattr(settings, 'NETJSONGRAPH_TIMEOUT', 8)
 LINK_EXPIRATION = getattr(settings, 'NETJSONGRAPH_LINK_EXPIRATION', 60)
+NODE_EXPIRATION = getattr(settings, 'NETJSONGRAPH_NODE_EXPIRATION', False)
 VISUALIZER_CSS = getattr(settings, 'NETJSONGRAPH_VISUALIZER_CSS', 'netjsongraph/css/style.css')

django_netjsongraph/tests/utils.py

@@ -171,6 +171,51 @@ def test_delete_expired_links(self):
         self.assertEqual(self.node_model.objects.count(), 2)
         self.assertEqual(self.link_model.objects.count(), 0)
 
+    @responses.activate
+    def test_delete_expired_nodes(self):
+        NODE_EXPIRATION = getattr(settings, 'NODE_EXPIRATION')
+        # Test with the default value(False)
+        # Should not delete
+        setattr(settings, 'NODE_EXPIRATION', False)
+        t = self.topology_model.objects.first()
+        t.parser = 'netdiff.NetJsonParser'
+        t.save()
+        expired_date = now() - timedelta(days=60)
+        n1 = self.node_model.objects.all()[0]
+        n2 = self.node_model.objects.all()[1]
+        self.node_model.objects.filter(pk=n1.pk).update(created=expired_date,
+                                                        modified=expired_date)
+        self.node_model.objects.filter(pk=n2.pk).update(created=expired_date,
+                                                        modified=expired_date)
+        empty_topology = json.dumps({
+            "type": "NetworkGraph",
+            "protocol": "OLSR",
+            "version": "0.8",
+            "metric": "ETX",
+            "nodes": [],
+            "links": []
+        })
+        responses.add(responses.GET,
+                      'http://127.0.0.1:9090',
+                      body=empty_topology,
+                      content_type='application/json')
+        self.topology_model.update_all('testnetwork')
+        self.assertEqual(self.node_model.objects.count(), 2)
+
+        # Test with a custom value
+        # Should delete
+        setattr(settings, 'NODE_EXPIRATION', 60)
+        expired_date = now() - timedelta(days=settings.NODE_EXPIRATION+10)
+        self.node_model.objects.filter(pk=n1.pk).update(created=expired_date,
+                                                        modified=expired_date)
+        self.node_model.objects.filter(pk=n2.pk).update(created=expired_date,
+                                                        modified=expired_date)
+        self.topology_model.update_all('testnetwork')
+        self.assertEqual(self.node_model.objects.count(), 0)
+        self.assertEqual(self.link_model.objects.count(), 0)
+        # Set the setting to it's original value
+        setattr(settings, 'NODE_EXPIRATION', NODE_EXPIRATION)
+
     @responses.activate
     def test_delete_expired_disabled(self):
         t = self.topology_model.objects.first()