Falcon multi-value query parameters fix

Author: p1c2u

Diff for: openapi_core/contrib/falcon/requests.py

@@ -11,6 +11,7 @@
 from werkzeug.datastructures import Headers
 from werkzeug.datastructures import ImmutableMultiDict
 
+from openapi_core.contrib.falcon.util import unpack_params
 from openapi_core.datatypes import RequestParameters
 
 
@@ -29,7 +30,7 @@ def __init__(
 
         # Path gets deduced by path finder against spec
         self.parameters = RequestParameters(
-            query=ImmutableMultiDict(list(self.request.params.items())),
+            query=ImmutableMultiDict(unpack_params(self.request.params)),
             header=Headers(self.request.headers),
             cookie=self.request.cookies,
         )

Diff for: openapi_core/contrib/falcon/util.py

@@ -0,0 +1,15 @@
+from typing import Any
+from typing import Dict
+from typing import Generator
+from typing import Tuple
+
+
+def unpack_params(
+    params: Dict[str, Any]
+) -> Generator[Tuple[str, Any], None, None]:
+    for k, v in params.items():
+        if isinstance(v, list):
+            for v2 in v:
+                yield (k, v2)
+        else:
+            yield (k, v)

Diff for: tests/integration/contrib/falcon/data/v3.0/falconproject/pets/resources.py

@@ -11,11 +11,19 @@ class PetListResource:
     def on_get(self, request, response):
         assert request.context.openapi
         assert not request.context.openapi.errors
-        assert request.context.openapi.parameters.query == {
-            "page": 1,
-            "limit": 12,
-            "search": "",
-        }
+        if "ids" in request.params:
+            assert request.context.openapi.parameters.query == {
+                "page": 1,
+                "limit": 2,
+                "search": "",
+                "ids": [1, 2],
+            }
+        else:
+            assert request.context.openapi.parameters.query == {
+                "page": 1,
+                "limit": 12,
+                "search": "",
+            }
         data = [
             {
                 "id": 12,

Diff for: tests/integration/contrib/falcon/test_falcon_project.py

@@ -67,6 +67,33 @@ def test_get_valid(self, client):
             ],
         }
 
+    def test_get_valid_multiple_ids(self, client):
+        headers = {
+            "Content-Type": "application/json",
+        }
+        query_string = "limit=2&ids=1&ids=2"
+
+        with pytest.warns(DeprecationWarning):
+            response = client.simulate_get(
+                "/v1/pets",
+                host="petstore.swagger.io",
+                headers=headers,
+                query_string=query_string,
+            )
+
+        assert response.status_code == 200
+        assert response.json == {
+            "data": [
+                {
+                    "id": 12,
+                    "name": "Cat",
+                    "ears": {
+                        "healthy": True,
+                    },
+                },
+            ],
+        }
+
     def test_post_server_invalid(self, client):
         response = client.simulate_post(
             "/v1/pets",