feat: Support for testing of examples in Parameter & Media Type objec…

…ts in Open API 3.0.

docs/changelog.rst

@@ -6,6 +6,11 @@ Changelog
 `Unreleased`_
 -------------
 
+Added
+~~~~~
+
+- Support for testing of examples in Parameter & Media Type objects in Open API 3.0. `#394`_
+
 Changed
 ~~~~~~~
 
@@ -667,6 +672,7 @@ Fixed
 .. _0.3.0: https://github.com/kiwicom/schemathesis/compare/v0.2.0...v0.3.0
 .. _0.2.0: https://github.com/kiwicom/schemathesis/compare/v0.1.0...v0.2.0
 
+.. _#394: https://github.com/kiwicom/schemathesis/issues/394
 .. _#386: https://github.com/kiwicom/schemathesis/issues/386
 .. _#383: https://github.com/kiwicom/schemathesis/issues/383
 .. _#381: https://github.com/kiwicom/schemathesis/issues/381

src/schemathesis/schemas.py

@@ -318,6 +318,11 @@ def process_by_type(self, endpoint: Endpoint, parameter: Dict[str, Any]) -> None
 
     def add_parameter(self, container: Optional[Dict[str, Any]], parameter: Dict[str, Any]) -> Dict[str, Any]:
         container = super().add_parameter(container, parameter)
+        if "example" in parameter["schema"]:
+            container["example"] = {parameter["name"]: parameter["schema"]["example"]}
+        # https://github.com/OAI/OpenAPI-Specification/blob/master/versions/3.0.2.md#parameter-object
+        # > Furthermore, if referencing a schema which contains an example,
+        # > the example value SHALL override the example provided by the schema
         if "example" in parameter:
             container["example"] = {parameter["name"]: parameter["example"]}
         return container
@@ -329,6 +334,11 @@ def process_body(self, endpoint: Endpoint, parameter: Dict[str, Any]) -> None:
         # Take the first media type object
         options = iter(parameter["content"].values())
         parameter = next(options)
+        # https://github.com/OAI/OpenAPI-Specification/blob/master/versions/3.0.2.md#media-type-object
+        # > Furthermore, if referencing a schema which contains an example,
+        # > the example value SHALL override the example provided by the schema
+        if "example" in parameter:
+            parameter["schema"]["example"] = parameter["example"]
         super().process_body(endpoint, parameter)
 
     def parameter_to_json_schema(self, data: Dict[str, Any]) -> Dict[str, Any]:

test/test_parametrization.py

@@ -182,7 +182,46 @@ def test(request, case):
 
 
 def test_specified_example_query(testdir):
-    # When the given query parameter contains an example
+    # When the given query parameter contains an example in the "schema" field
+    testdir.make_test(
+        """
+from hypothesis import Phase
+
+@schema.parametrize()
+@settings(max_examples=1, phases=[Phase.explicit])
+def test(request, case):
+    request.config.HYPOTHESIS_CASES += 1
+    assert case.query == {"id": "test"}
+""",
+        schema={
+            "openapi": "3.0.2",
+            "info": {"title": "Test", "description": "Test", "version": "0.1.0"},
+            "paths": {
+                "/query": {
+                    "get": {
+                        "parameters": [
+                            {
+                                "name": "id",
+                                "in": "query",
+                                "required": True,
+                                "schema": {"type": "string", "example": "test"},
+                            }
+                        ],
+                        "responses": {"200": {"description": "OK"}},
+                    }
+                }
+            },
+        },
+    )
+
+    result = testdir.runpytest("-v", "-s")
+    # Then this example should be used in tests
+    result.assert_outcomes(passed=1)
+    result.stdout.re_match_lines([r"Hypothesis calls: 1$"])
+
+
+def test_specified_example_parameter_override(testdir):
+    # When the given parameter contains an example
     testdir.make_test(
         """
 from hypothesis import Phase
@@ -205,7 +244,7 @@ def test(request, case):
                                 "in": "query",
                                 "required": True,
                                 "example": "test",
-                                "schema": {"type": "string"},
+                                "schema": {"type": "string", "example": "NOT test"},
                             }
                         ],
                         "responses": {"200": {"description": "OK"}},
@@ -221,6 +260,50 @@ def test(request, case):
     result.stdout.re_match_lines([r"Hypothesis calls: 1$"])
 
 
+def test_specified_example_body_media_type_override(testdir):
+    # When the given requestBody parameter contains an example specified in Media Type Object (not in Schema Object)
+    testdir.make_test(
+        """
+from hypothesis import Phase
+
+@schema.parametrize()
+@settings(max_examples=1, phases=[Phase.explicit])
+def test(request, case):
+    request.config.HYPOTHESIS_CASES += 1
+    assert case.body == {"name": "John"}
+""",
+        schema={
+            "openapi": "3.0.2",
+            "info": {"title": "Test", "description": "Test", "version": "0.1.0"},
+            "paths": {
+                "/body": {
+                    "post": {
+                        "requestBody": {
+                            "content": {
+                                "application/json": {
+                                    "schema": {
+                                        "type": "object",
+                                        "properties": {"name": {"type": "string"}},
+                                        "required": ["name"],
+                                        "example": {"name": "NOT John"},
+                                    },
+                                    "example": {"name": "John"},
+                                }
+                            }
+                        },
+                        "responses": {"200": {"description": "OK"}},
+                    }
+                }
+            },
+        },
+    )
+
+    result = testdir.runpytest("-v", "-s")
+    # Then this example should be used in tests, not the example from the schema
+    result.assert_outcomes(passed=1)
+    result.stdout.re_match_lines([r"Hypothesis calls: 1$"])
+
+
 def test_deselecting(testdir):
     # When pytest selecting is applied via "-k" option
     testdir.make_test(