def test_create_message():
    response = client.post("/messages", params={"input_message": "Hello"})
    assert response.status_code == 200, response.text
    assert response.json() == {
        "input": "Hello",
        "output": {"body": "Processed: Hello", "events": []},
    }


def test_openapi_schema():
    response = client.get("/openapi.json")
    assert response.status_code == 200, response.text

{* ../../docs_src/path_operation_advanced_configuration/tutorial004_py310.py hl[17:27] *}

## Responses Adicionales { #additional-responses }

Probablemente has visto cómo declarar el `response_model` y el `status_code` para una *path operation*.

Eso define los metadatos sobre el response principal de una *path operation*.

También puedes declarar responses adicionales con sus modelos, códigos de estado, etc.

                        "summary": "Test",
                        "operationId": "test__get",
                        "responses": {
                            "200": {
                                "description": "Successful Response",
                                "content": {
                                    "application/json": {
                                        "schema": {

Por exemplo, você pode querer retornar uma *response* em *plain text* ao invés de um JSON para os seguintes erros:

{* ../../docs_src/handling_errors/tutorial004_py310.py hl[3:4,9:11,25] *}

/// note | Detalhes Técnicos

Você pode usar `from starlette.responses import PlainTextResponse`.

import (
	"context"
	"errors"
)

// A Stream is a two-way stream.
// All responses *must* be read by the caller.
// If the call is canceled through the context,
// the appropriate error will be returned.
type Stream struct {
	// responses from the remote server.
	// Channel will be closed after error or when remote closes.
	// All responses *must* be read by the caller until either an error is returned or the channel is closed.

                "msg": "Field required",
                "input": None,
            },
        ]
    }


def test_openapi_schema(client: TestClient):
    response = client.get("/openapi.json")
    assert response.status_code == 200, response.text
    assert response.json() == snapshot(
        {
            "openapi": "3.1.0",
            "info": {"title": "FastAPI", "version": "0.1.0"},
            "paths": {

	}
	// Start processing requests.
	close(processHandler)

	// Drain responses
	got := 0
	for resp := range st.responses {
		// t.Log("got response", resp)
		errFatal(resp.Err)
		if resp.Msg[0] != byte(got) {
			t.Error("expected response", got, "got", resp.Msg[0])
		}
		got++
	}
	if got != 100 {
		t.Error("expected 100 responses, got", got)
	}
}

     *
     * @param request the request to send
     * @param response the response object to populate
     * @param timeout the maximum time to wait for the response in milliseconds
     * @throws IOException if an I/O error occurs during communication
     */
    public synchronized void sendrecv(final Request request, final Response response, long timeout) throws IOException {

/// warning

上の例のように `Response` を直接返すと、それはそのまま返されます。

モデルなどによってシリアライズされません。

必要なデータが含まれていること、そして（`JSONResponse` を使用している場合）値が有効な JSON であることを確認してください。

///

/// note | 技術詳細

`from starlette.responses import JSONResponse` を使うこともできます。

**FastAPI** は開発者の利便性のために、`fastapi.responses` と同じ `starlette.responses` を提供しています。しかし、利用可能なレスポンスのほとんどは Starlette から直接提供されています。`status` も同様です。

///

  fun finishRequest()

  /**
   * Parses bytes of a response header from an HTTP transport.
   *
   * @param expectContinue true to return null if this is an intermediate response with a "100"
   * response code. Otherwise this method never returns null.
   */
  @Throws(IOException::class)
  fun readResponseHeaders(expectContinue: Boolean): Response.Builder?

  @Throws(IOException::class)