René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Array of files in multipart/form-data is not handled correctly","articleBody":"**Describe the bug**\r\nFor multipart/form-data with an array of files, generated code tries to serialize the array of files as JSON.\r\n\r\n**To Reproduce**\r\nSteps to reproduce the behavior:\r\n1. Using the spec included in this bug report, run `openapi-python-client --path spec.json`\r\n2. Try to run the following code:\r\n```\r\nfrom multiple_upload_client.client import Client\r\nfrom multiple_upload_client.models import UploadMultipleMultipartData\r\nfrom multiple_upload_client.api.files import upload_multiple\r\nfrom multiple_upload_client.types import File\r\n\r\nclient = Client(base_url=\"http://localhost:8080\")\r\nupload_multiple.sync_detailed(\r\n  client=client,\r\n  multipart_data=UploadMultipleMultipartData(\r\n    files=[\r\n      File(\r\n        payload=open(\"path to some local file\", \"rb\"),\r\n        file_name=\"sample.jpeg\",\r\n        mime_type=\"image/jpeg\"\r\n      )\r\n    ]\r\n  )\r\n)\r\n```\r\n\r\nThe following error occurs:\r\n```\r\nTraceback (most recent call last):\r\n  File \"test_multiple_upload.py\", line 7, in \u003cmodule\u003e\r\n    upload_multiple.sync_detailed(\r\n  File \"/Users/davidzeng/butler/src/experimental/test-codegen/opc/multiple-upload-client/multiple_upload_client/api/files/upload_multiple.py\", line 62, in sync_detailed\r\n    kwargs = _get_kwargs(\r\n  File \"/Users/davidzeng/butler/src/experimental/test-codegen/opc/multiple-upload-client/multiple_upload_client/api/files/upload_multiple.py\", line 20, in _get_kwargs\r\n    multipart_multipart_data = multipart_data.to_multipart()\r\n  File \"/Users/davidzeng/butler/src/experimental/test-codegen/opc/multiple-upload-client/multiple_upload_client/models/upload_multiple_multipart_data.py\", line 47, in to_multipart\r\n    files = (None, json.dumps(_temp_files).encode(), \"application/json\")\r\n  File \"/usr/local/opt/python@3.8/Frameworks/Python.framework/Versions/3.8/lib/python3.8/json/__init__.py\", line 231, in dumps\r\n    return _default_encoder.encode(obj)\r\n  File \"/usr/local/opt/python@3.8/Frameworks/Python.framework/Versions/3.8/lib/python3.8/json/encoder.py\", line 199, in encode\r\n    chunks = self.iterencode(o, _one_shot=True)\r\n  File \"/usr/local/opt/python@3.8/Frameworks/Python.framework/Versions/3.8/lib/python3.8/json/encoder.py\", line 257, in iterencode\r\n    return _iterencode(o, 0)\r\n  File \"/usr/local/opt/python@3.8/Frameworks/Python.framework/Versions/3.8/lib/python3.8/json/encoder.py\", line 179, in default\r\n    raise TypeError(f'Object of type {o.__class__.__name__} '\r\nTypeError: Object of type BufferedReader is not JSON serializable\r\n```\r\n\r\n**Expected behavior**\r\nThe generated code for handling an array of files seems to be trying to serialize the files as json:\r\n```\r\n    def to_multipart(self) -\u003e Dict[str, Any]:\r\n        files: Union[Unset, Tuple[None, bytes, str]] = UNSET\r\n        if not isinstance(self.files, Unset):\r\n            _temp_files = []\r\n            for files_item_data in self.files:\r\n                files_item = files_item_data.to_tuple()\r\n\r\n                _temp_files.append(files_item)\r\n            files = (None, json.dumps(_temp_files).encode(), \"application/json\")\r\n\r\n        field_dict: Dict[str, Any] = {}\r\n        field_dict.update(\r\n            {key: (None, str(value).encode(), \"text/plain\") for key, value in self.additional_properties.items()}\r\n        )\r\n        field_dict.update({})\r\n        if files is not UNSET:\r\n            field_dict[\"files\"] = files\r\n\r\n        return field_dict\r\n```\r\n\r\nBased on https://www.python-httpx.org/advanced/#multipart-file-encoding, we should probably be doing something more like the following, treating the multipart data as a list of tuples, with field keys that can repeat. Each file is added to the list under the same \"files\" key:\r\n```\r\n    def to_multipart(self) -\u003e List[Tuple[str, FileJsonType]]:\r\n        field_list = []\r\n        if not isinstance(self.files, Unset):\r\n            for files_item_data in self.files:\r\n                files_item = files_item_data.to_tuple()\r\n                field_list.append((\"files\", files_item))\r\n\r\n        for key, value in self.additional_properties.items():\r\n            field_list.append((key, (None, str(value).encode(), \"text/plain\")))\r\n\r\n        return field_list\r\n```\r\n\r\n**OpenAPI Spec File**\r\n```\r\n{\r\n  \"openapi\": \"3.0.0\",\r\n  \"paths\": {\r\n    \"/api/files/upload_multiple\": {\r\n      \"post\": {\r\n        \"operationId\": \"uploadMultiple\",\r\n        \"summary\": \"Uploads multiple files\",\r\n        \"requestBody\": {\r\n          \"content\": {\r\n            \"multipart/form-data\": {\r\n              \"schema\": {\r\n                \"type\": \"object\",\r\n                \"properties\": {\r\n                  \"files\": {\r\n                    \"type\": \"array\",\r\n                    \"items\": {\r\n                      \"type\": \"string\",\r\n                      \"format\": \"binary\"\r\n                    }\r\n                  }\r\n                }\r\n              }\r\n            }\r\n          },\r\n          \"required\": true\r\n        },\r\n        \"parameters\": [],\r\n        \"responses\": {\r\n          \"201\": {\r\n            \"description\": \"Returns some random string\",\r\n            \"content\": {\r\n              \"application/json\": {\r\n                \"schema\": {\r\n                  \"type\": \"string\"\r\n                }\r\n              }\r\n            }\r\n          }\r\n        },\r\n        \"tags\": [\r\n          \"files\"\r\n        ]\r\n      }\r\n    }\r\n  },\r\n  \"info\": {\r\n    \"title\": \"Multiple Upload\",\r\n    \"description\": \"Test spec for array of files in multipart/form-data\",\r\n    \"version\": \"0.0.1\",\r\n    \"contact\": {}\r\n  },\r\n  \"tags\": [],\r\n  \"servers\": [],\r\n  \"components\": {\r\n    \"schemas\": {}\r\n  }\r\n}\r\n```\r\n\r\n**Desktop (please complete the following information):**\r\n - OS: macOS 10.15.7\r\n - Python Version: 3.8.13\r\n - openapi-python-client version: 0.11.6\r\n\r\n**Additional context**\r\nAdd any other context about the problem here.\r\n","author":{"url":"https://github.com/davidlizeng","@type":"Person","name":"davidlizeng"},"datePublished":"2022-10-21T23:13:01.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":3},"url":"https://github.com/692/openapi-python-client/issues/692"}