Refactor REST API serializers to avoid circular imports

netbox/dcim/api/serializers_/base.py

@@ -0,0 +1,38 @@
+from drf_spectacular.types import OpenApiTypes
+from drf_spectacular.utils import extend_schema_field
+from rest_framework import serializers
+
+from netbox.constants import NESTED_SERIALIZER_PREFIX
+from utilities.api import get_serializer_for_model
+
+__all__ = (
+    'ConnectedEndpointsSerializer',
+)
+
+
+class ConnectedEndpointsSerializer(serializers.ModelSerializer):
+    """
+    Legacy serializer for pre-v3.3 connections
+    """
+    connected_endpoints_type = serializers.SerializerMethodField(read_only=True)
+    connected_endpoints = serializers.SerializerMethodField(read_only=True)
+    connected_endpoints_reachable = serializers.SerializerMethodField(read_only=True)
+
+    @extend_schema_field(OpenApiTypes.STR)
+    def get_connected_endpoints_type(self, obj):
+        if endpoints := obj.connected_endpoints:
+            return f'{endpoints[0]._meta.app_label}.{endpoints[0]._meta.model_name}'
+
+    @extend_schema_field(serializers.ListField)
+    def get_connected_endpoints(self, obj):
+        """
+        Return the appropriate serializer for the type of connected object.
+        """
+        if endpoints := obj.connected_endpoints:
+            serializer = get_serializer_for_model(endpoints[0], prefix=NESTED_SERIALIZER_PREFIX)
+            context = {'request': self.context['request']}
+            return serializer(endpoints, many=True, context=context).data
+
+    @extend_schema_field(serializers.BooleanField)
+    def get_connected_endpoints_reachable(self, obj):
+        return obj._path and obj._path.is_complete and obj._path.is_active