Raise an error in generated clients when receiving an unknown response code

Author: dbanty

CHANGELOG.md

@@ -6,6 +6,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## 0.1.1 - 2020-03-06
 - Fix mypy issue in generated models `from_dict` with datetime or reference properties
+- Generated clients now raise an `ApiResponseError` if they receive a response that was not declared
 
 ## 0.1.0 - 2020-02-28
 - Initial Release

openapi_python_client/__init__.py

@@ -110,6 +110,11 @@ def _build_api(self) -> None:
         api_dir.mkdir()
         api_init = api_dir / "__init__.py"
         api_init.write_text('""" Contains all methods for accessing the API """')
+
+        api_errors = api_dir / "errors.py"
+        errors_template = self.env.get_template("errors.pyi")
+        api_errors.write_text(errors_template.render())
+
         endpoint_template = self.env.get_template("endpoint_module.pyi")
         for tag, collection in self.openapi.endpoint_collections_by_tag.items():
             module_path = api_dir / f"{tag}.py"

openapi_python_client/templates/README.md

@@ -32,3 +32,6 @@ Things to know:
 1. All path/query params, and bodies become method arguments.
 1. If your endpoint had any tags on it, the first tag will be used as a module name for the function (my_tag above)
 1. Any endpoint which did not have a tag will be in `{{ package_name }}.api.default`
+1. If the API returns a response code that was not declared in the OpenAPI document, a 
+    `{{ package_name }}.api.errors.ApiResponseError` wil be raised 
+    with the `response` attribute set to the `requests.Response` that was received.

openapi_python_client/templates/endpoint_module.pyi

@@ -3,6 +3,7 @@ from typing import Dict, List, Optional, Union
 
 import requests
 
+from .errors import ApiResponseError
 from ..client import AuthenticatedClient, Client
 
 {% for relative in collection.relative_imports %}
@@ -69,4 +70,6 @@ def {{ endpoint.name }}(
     if response.status_code == {{ response.status_code }}:
         return {{ response.constructor() }}
     {% endfor %}
+    else:
+        raise ApiResponseError(response=response)
 {% endfor %}

openapi_python_client/templates/errors.pyi

@@ -0,0 +1,9 @@
+from requests import Response
+
+
+class ApiResponseError(Exception):
+    """ An exception raised when an unknown response occurs """
+
+    def __init__(self, *, response: Response):
+        super().__init__()
+        self.response: Response = response

tests/test___init__.py

@@ -220,6 +220,7 @@ def test__build_models(self, mocker):
 
     def test__build_api(self, mocker):
         import pathlib
+        from jinja2 import Template
         from openapi_python_client import _Project, OpenAPI
 
         openapi = mocker.MagicMock(autospec=OpenAPI, title="My Test API")
@@ -232,10 +233,12 @@ def test__build_api(self, mocker):
         project.package_dir = mocker.MagicMock()
         client_path = mocker.MagicMock()
         api_init = mocker.MagicMock(autospec=pathlib.Path)
+        api_errors = mocker.MagicMock(autospec=pathlib.Path)
         collection_1_path = mocker.MagicMock(autospec=pathlib.Path)
         collection_2_path = mocker.MagicMock(autospec=pathlib.Path)
         api_paths = {
             "__init__.py": api_init,
+            "errors.py": api_errors,
             f"{tag_1}.py": collection_1_path,
             f"{tag_2}.py": collection_2_path,
         }
@@ -246,10 +249,12 @@ def test__build_api(self, mocker):
             "api": api_dir,
         }
         project.package_dir.__truediv__.side_effect = lambda x: package_paths[x]
-        client_template = mocker.MagicMock()
-        endpoint_template = mocker.MagicMock()
+        client_template = mocker.MagicMock(autospec=Template)
+        errors_template = mocker.MagicMock(autospec=Template)
+        endpoint_template = mocker.MagicMock(autospec=Template)
         templates = {
             "client.pyi": client_template,
+            "errors.pyi": errors_template,
             "endpoint_module.pyi": endpoint_template,
         }
         mocker.patch.object(project.env, "get_template", autospec=True, side_effect=lambda x: templates[x])
@@ -268,6 +273,8 @@ def test__build_api(self, mocker):
         api_dir.mkdir.assert_called_once()
         api_dir.__truediv__.assert_has_calls([mocker.call(key) for key in api_paths])
         api_init.write_text.assert_called_once_with('""" Contains all methods for accessing the API """')
+        errors_template.render.assert_called_once()
+        api_errors.write_text.assert_called_once_with(errors_template.render())
         endpoint_template.render.assert_has_calls(
             [mocker.call(collection=collection_1), mocker.call(collection=collection_2),]
         )