from fastapi import FastAPI, Form from fastapi.testclient import TestClient from typing_extensions import Annotated app = FastAPI() @app.post("/form/") def post_form(username: Annotated[str, Form()]): return username client = TestClient(app) def test_single_form_field(): response = client.post("/form/", data={"username": "Rick"}) assert response.status_code == 200, response.text assert response.json() == "Rick" def test_openapi_schema(): response = client.get("/openapi.json") assert response.status_code == 200, response.text assert response.json() == { "openapi": "3.1.0", "info": {"title": "FastAPI", "version": "0.1.0"}, "paths": { "/form/": { "post": { "summary": "Post Form", "operationId": "post_form_form__post", "requestBody": { "content": { "application/x-www-form-urlencoded": { "schema": { "$ref": "#/components/schemas/Body_post_form_form__post" } } }, "required": True, }, "responses": { "200": { "description": "Successful Response", "content": {"application/json": {"schema": {}}}, }, "422": { "description": "Validation Error", "content": { "application/json": { "schema": { "$ref": "#/components/schemas/HTTPValidationError" } } }, }, }, } } }, "components": { "schemas": { "Body_post_form_form__post": { "properties": {"username": {"type": "string", "title": "Username"}}, "type": "object", "required": ["username"], "title": "Body_post_form_form__post", }, "HTTPValidationError": { "properties": { "detail": { "items": {"$ref": "#/components/schemas/ValidationError"}, "type": "array", "title": "Detail", } }, "type": "object", "title": "HTTPValidationError", }, "ValidationError": { "properties": { "loc": { "items": { "anyOf": [{"type": "string"}, {"type": "integer"}] }, "type": "array", "title": "Location", }, "msg": {"type": "string", "title": "Message"}, "type": {"type": "string", "title": "Error Type"}, }, "type": "object", "required": ["loc", "msg", "type"], "title": "ValidationError", }, } }, }