feat(parsers): ignore sibling elements of $ref according to OpenAPI 3.0 specification

spec2sdk/parsers/resolver.py

@@ -68,13 +68,14 @@ def resolve_reference(reference: str) -> dict:
 
             return self._resolved_references[reference_id]
 
-        return {
-            new_key: new_value
-            for key, value in schema.items()
-            for new_key, new_value in (
-                resolve_reference(value) if key == "$ref" else {key: resolve_value(value)}
-            ).items()
-        }
+        # Object containing $ref cannot be extended with additional properties
+        # and any properties added SHALL be ignored.
+        # https://spec.openapis.org/oas/v3.0.0.html#reference-object
+        return (
+            resolve_reference(schema["$ref"])
+            if "$ref" in schema
+            else {key: resolve_value(value) for key, value in schema.items()}
+        )
 
     def parse(self, url: str) -> dict:
         schema_loader = SchemaLoader(schema_url=url)

tests/parsers/resolver/test_data/references_with_siblings/expected_output/schema.json

@@ -0,0 +1,46 @@
+{
+  "components": {
+    "schemas": {
+      "HealthStatus": {
+        "description": "Schema description",
+        "properties": {
+          "status": {
+            "type": "string"
+          }
+        },
+        "type": "object"
+      }
+    }
+  },
+  "info": {
+    "title": "Example API",
+    "version": "1.0"
+  },
+  "openapi": "3.0.0",
+  "paths": {
+    "/health": {
+      "get": {
+        "operationId": "healthCheck",
+        "responses": {
+          "200": {
+            "content": {
+              "application/json": {
+                "schema": {
+                  "description": "Schema description",
+                  "properties": {
+                    "status": {
+                      "type": "string"
+                    }
+                  },
+                  "type": "object",
+                  "x-schema-name": "HealthStatus"
+                }
+              }
+            },
+            "description": "Successful response"
+          }
+        }
+      }
+    }
+  }
+}

tests/parsers/resolver/test_data/references_with_siblings/input/api.yml

@@ -0,0 +1,28 @@
+openapi: 3.0.0
+
+info:
+  title: Example API
+  version: '1.0'
+
+paths:
+  /health:
+    get:
+      operationId: healthCheck
+      responses:
+        '200':
+          description: Successful response
+          content:
+            application/json:
+              schema:
+                $ref: '#/components/schemas/HealthStatus'
+                description: Response content description
+                nullable: true
+
+components:
+  schemas:
+    HealthStatus:
+      description: Schema description
+      type: object
+      properties:
+        status:
+          type: string

tests/parsers/resolver/test_resolver.py

@@ -12,7 +12,7 @@
 TEST_DATA_DIR = Path(__file__).parent / "test_data"
 
 
-@pytest.mark.parametrize("test_data_name", ("local_references", "remote_references"))
+@pytest.mark.parametrize("test_data_name", ("local_references", "remote_references", "references_with_siblings"))
 def test_resolve_references(test_data_name: str):
     data_dir = TEST_DATA_DIR / test_data_name
     spec_path = data_dir / "input" / "api.yml"