Prevent duplicating instance links

In receptor address post-save method:
- Fixed detecting if address was missing
a link from control nodes
- Use InstanceLink create_or_update to prevent
adding duplicate InstanceLink source and target
peers

In instance serializer create_or_update,
delete receptor addresses first before doing
instance create or update. This ensures that we don't
trigger unnecessary post-save methods that might
attempt to manipulate receptor addresses that
will just be removed later.

Signed-off-by: Seth Foster <fosterbseth@gmail.com>

awx/api/serializers.py

@@ -5598,27 +5598,32 @@ class InstanceSerializer(BaseSerializer):
 
     def create_or_update(self, validated_data, obj=None, create=True):
         # create a managed receptor address if listener port is defined
-        kwargs = dict()
+        port = validated_data.pop('listener_port', -1)
-        if 'listener_port' in validated_data:
+        peers_from_control_nodes = validated_data.pop('peers_from_control_nodes', -1)
-            kwargs['port'] = validated_data.pop('listener_port')
+
-        if 'peers_from_control_nodes' in validated_data:
+        # delete the receptor address if the port is explicitly set to None
-            kwargs['peers_from_control_nodes'] = validated_data.pop('peers_from_control_nodes')
+        if obj and port == None:
+            obj.receptor_addresses.filter(address=obj.hostname).delete()
 
         if create:
             instance = super(InstanceSerializer, self).create(validated_data)
         else:
             instance = super(InstanceSerializer, self).update(obj, validated_data)
+            instance.refresh_from_db()  # instance canonical address lookup is deferred, so needs to be reloaded
 
-        # delete the receptor address if the port is expolisitly set to None
-        if 'port' in kwargs and not kwargs['port']:
-            instance.receptor_addresses.filter(address=instance.hostname).delete()
         # only create or update if port is defined in validated_data or already exists in the
         # canonical address
         # this prevents creating a receptor address if peers_from_control_nodes is in
         # validated_data but a port is not set
-        elif kwargs and ('port' in kwargs or instance.canonical_address_port):
+        if (port != None and port != -1) or instance.canonical_address_port:
-            kwargs['canonical'] = True
+            kwargs = {}
-            instance.receptor_addresses.update_or_create(address=instance.hostname, defaults=kwargs)
+            if port != -1:
+                kwargs['port'] = port
+            if peers_from_control_nodes != -1:
+                kwargs['peers_from_control_nodes'] = peers_from_control_nodes
+            if kwargs:
+                kwargs['canonical'] = True
+                instance.receptor_addresses.update_or_create(address=instance.hostname, defaults=kwargs)
 
         return instance
 

awx/main/models/ha.py

@@ -522,13 +522,14 @@ def receptor_address_saved(sender, instance, **kwargs):
 
     control_instances = set(Instance.objects.filter(node_type__in=[Instance.Types.CONTROL, Instance.Types.HYBRID]))
     if address.peers_from_control_nodes:
-        # FIXME: you ought to be able to have more connections than just the control instances
+        # if control_instances is not a subset of current peers of address, then
-        if set(address.peers_from.all()) != control_instances:
+        # that means we need to add some InstanceLinks
+        if not control_instances <= set(address.peers_from.all()):
             with disable_activity_stream():
-                address.peers_from.add(*control_instances)
+                for control_instance in control_instances:
+                    InstanceLink.objects.update_or_create(source=control_instance, target=address)
                 schedule_write_receptor_config()
     else:
-        # FIXME: you shouldn't unconditionally remove every peer when disabling peers_from_control_nodes
         if address.peers_from.exists():
             with disable_activity_stream():
                 address.peers_from.remove(*control_instances)