openapi - schema ref nesting

resolve referenced nested references while taking care of self references

aiopenapi3/base.py

@@ -286,6 +286,9 @@ def resolve_jp(self, jp):
                 node = node[int(part)]
             elif isinstance(node, ObjectBase):
                 part = Model.nameof(part)
+                if isinstance(node, ReferenceBase) and node._target is None:
+                    """unresolved reference - requires resolving the reference first"""
+                    return node
                 if not hasattr(node, part):
                     raise ReferenceResolutionError(f"Invalid path {path[:idx]} in Reference")
                 node = getattr(node, part)

aiopenapi3/openapi.py

@@ -747,7 +747,18 @@ def resolve_jr(self, root: RootBase, obj, value: Reference):
             root = self._documents[url]
 
         try:
-            return root.resolve_jp(jp)
+            while True:
+                r = root.resolve_jp(jp)
+                if isinstance(r, ReferenceBase):
+                    """
+                    returned node is a unresolved reference
+                    resolve & retry
+                    """
+                    r._target = root.resolve_jp(r.ref)
+                    if isinstance(r._target, ReferenceBase) and r.ref == r._target.ref:
+                        return r
+                    continue
+                return r
         except ReferenceResolutionError as e:
             # add metadata to the error
             e.element = obj

tests/conftest.py

@@ -488,3 +488,8 @@ def with_paths_server_variables(openapi_version):
 @pytest.fixture
 def with_paths_response_error():
     yield _get_parsed_yaml("paths-response-error.yaml")
+
+
+@pytest.fixture
+def with_schema_ref_nesting():
+    yield _get_parsed_yaml("schema-ref-nesting.yaml")

tests/fixtures/schema-ref-nesting.yaml

@@ -0,0 +1,54 @@
+openapi: 3.0.0
+info:
+  title: OpenStreetMap circular refs
+  description: This is the editing API for OpenStreetMap.
+  version: '0.6'
+servers:
+  - url: '/'
+paths:
+  /api/0.6/map:
+    get:
+      summary: Retrieves map data by the given bounding box.
+      description: |
+        The operation returns:
+      operationId: getMapDataByBoundingBox
+      responses:
+        '200':
+          description: okay
+          content:
+            application/json:
+              schema:
+                type: object
+                properties:
+                  elements:
+                    type: array
+                    items:
+                      oneOf:
+                        - $ref: '#/components/schemas/Node'
+components:
+  schemas:
+    Node:
+      allOf:
+        - $ref: '#/components/schemas/Way/allOf/0'
+    Way:
+      allOf:
+        - type: object
+          properties:
+            type:
+              type: string
+    Relation:
+      allOf:
+        - type: object
+          properties:
+            members:
+              type: array
+              items:
+                type: object
+                properties:
+                  type:
+                    $ref: '#/paths/~1api~10.6~1map/get/responses/200/content/application~1json/schema/properties/elements/items/oneOf/0/allOf/0/properties/type'
+          required:
+            - members
+externalDocs:
+  description: Find more information on the OSM wiki
+  url: 'https://wiki.openstreetmap.org/'

tests/schema_test.py

@@ -465,3 +465,8 @@ def test_schema_pathitems(httpx_mock, with_schema_pathitems):
 def test_schema_baseurl_v20(with_schema_baseurl_v20):
     api = OpenAPI("/", with_schema_baseurl_v20, session_factory=httpx.Client)
     assert api.url == yarl.URL("https://api.example.com:81/v1")
+
+
+def test_schema_ref_nesting(with_schema_ref_nesting):
+    for i in range(10):
+        OpenAPI("/", with_schema_ref_nesting)