🐛 Admit valid types for Pydantic fields as responses models (#1017)

tests/test_response_model_invalid.py

@@ -0,0 +1,45 @@
+from typing import List
+
+import pytest
+from fastapi import FastAPI
+from fastapi.exceptions import FastAPIError
+
+
+class NonPydanticModel:
+    pass
+
+
+def test_invalid_response_model_raises():
+    with pytest.raises(FastAPIError):
+        app = FastAPI()
+
+        @app.get("/", response_model=NonPydanticModel)
+        def read_root():
+            pass  # pragma: nocover
+
+
+def test_invalid_response_model_sub_type_raises():
+    with pytest.raises(FastAPIError):
+        app = FastAPI()
+
+        @app.get("/", response_model=List[NonPydanticModel])
+        def read_root():
+            pass  # pragma: nocover
+
+
+def test_invalid_response_model_in_responses_raises():
+    with pytest.raises(FastAPIError):
+        app = FastAPI()
+
+        @app.get("/", responses={"500": {"model": NonPydanticModel}})
+        def read_root():
+            pass  # pragma: nocover
+
+
+def test_invalid_response_model_sub_type_in_responses_raises():
+    with pytest.raises(FastAPIError):
+        app = FastAPI()
+
+        @app.get("/", responses={"500": {"model": List[NonPydanticModel]}})
+        def read_root():
+            pass  # pragma: nocover

tests/test_response_model_sub_types.py

@@ -0,0 +1,160 @@
+from typing import List
+
+from fastapi import FastAPI
+from pydantic import BaseModel
+from starlette.testclient import TestClient
+
+
+class Model(BaseModel):
+    name: str
+
+
+app = FastAPI()
+
+
+@app.get("/valid1", responses={"500": {"model": int}})
+def valid1():
+    pass
+
+
+@app.get("/valid2", responses={"500": {"model": List[int]}})
+def valid2():
+    pass
+
+
+@app.get("/valid3", responses={"500": {"model": Model}})
+def valid3():
+    pass
+
+
+@app.get("/valid4", responses={"500": {"model": List[Model]}})
+def valid4():
+    pass
+
+
+openapi_schema = {
+    "openapi": "3.0.2",
+    "info": {"title": "FastAPI", "version": "0.1.0"},
+    "paths": {
+        "/valid1": {
+            "get": {
+                "summary": "Valid1",
+                "operationId": "valid1_valid1_get",
+                "responses": {
+                    "200": {
+                        "description": "Successful Response",
+                        "content": {"application/json": {"schema": {}}},
+                    },
+                    "500": {
+                        "description": "Internal Server Error",
+                        "content": {
+                            "application/json": {
+                                "schema": {
+                                    "title": "Response 500 Valid1 Valid1 Get",
+                                    "type": "integer",
+                                }
+                            }
+                        },
+                    },
+                },
+            }
+        },
+        "/valid2": {
+            "get": {
+                "summary": "Valid2",
+                "operationId": "valid2_valid2_get",
+                "responses": {
+                    "200": {
+                        "description": "Successful Response",
+                        "content": {"application/json": {"schema": {}}},
+                    },
+                    "500": {
+                        "description": "Internal Server Error",
+                        "content": {
+                            "application/json": {
+                                "schema": {
+                                    "title": "Response 500 Valid2 Valid2 Get",
+                                    "type": "array",
+                                    "items": {"type": "integer"},
+                                }
+                            }
+                        },
+                    },
+                },
+            }
+        },
+        "/valid3": {
+            "get": {
+                "summary": "Valid3",
+                "operationId": "valid3_valid3_get",
+                "responses": {
+                    "200": {
+                        "description": "Successful Response",
+                        "content": {"application/json": {"schema": {}}},
+                    },
+                    "500": {
+                        "description": "Internal Server Error",
+                        "content": {
+                            "application/json": {
+                                "schema": {"$ref": "#/components/schemas/Model"}
+                            }
+                        },
+                    },
+                },
+            }
+        },
+        "/valid4": {
+            "get": {
+                "summary": "Valid4",
+                "operationId": "valid4_valid4_get",
+                "responses": {
+                    "200": {
+                        "description": "Successful Response",
+                        "content": {"application/json": {"schema": {}}},
+                    },
+                    "500": {
+                        "description": "Internal Server Error",
+                        "content": {
+                            "application/json": {
+                                "schema": {
+                                    "title": "Response 500 Valid4 Valid4 Get",
+                                    "type": "array",
+                                    "items": {"$ref": "#/components/schemas/Model"},
+                                }
+                            }
+                        },
+                    },
+                },
+            }
+        },
+    },
+    "components": {
+        "schemas": {
+            "Model": {
+                "title": "Model",
+                "required": ["name"],
+                "type": "object",
+                "properties": {"name": {"title": "Name", "type": "string"}},
+            }
+        }
+    },
+}
+
+client = TestClient(app)
+
+
+def test_openapi_schema():
+    response = client.get("/openapi.json")
+    assert response.status_code == 200
+    assert response.json() == openapi_schema
+
+
+def test_path_operations():
+    response = client.get("/valid1")
+    assert response.status_code == 200
+    response = client.get("/valid2")
+    assert response.status_code == 200
+    response = client.get("/valid3")
+    assert response.status_code == 200
+    response = client.get("/valid4")
+    assert response.status_code == 200