## Example { #example }

Here's an example *path operation* with parameters using some of the above types.

{* ../../docs_src/extra_data_types/tutorial001_an_py310.py hl[1,3,12:16] *}

Note that the parameters inside the function have their natural data type, and you can, for example, perform normal date manipulations, like:

Первое значение является значением по умолчанию, вы можете передать все дополнительные параметры валидации или аннотации:

{* ../../docs_src/header_params/tutorial001_an_py310.py hl[9] *}

/// note | Технические детали

`Header` - это "родственный" класс `Path`, `Query` и `Cookie`. Он также наследуется от того же общего класса `Param`.

 *     String name = header.getName();
 *     String value = header.getValue();
 *     boolean isValid = header.isValid();
 * </pre>
 *
 * <p>Note: The name should not be blank and the value should not be null for the header to be considered valid.</p>
 *
 * @see java.io.Serializable
 */
public class RequestHeader implements Serializable {

   * // counters.
   * ListenableFuture<Integer> faultTolerantFuture =
   *     fetchCounters().catching(FetchException.class, x -> 0, directExecutor());
   * }
   *
   * <p>When selecting an executor, note that {@code directExecutor} is dangerous in some cases. See
   * the discussion in the {@link #addListener} documentation. All its warnings about heavyweight

REM Causes the JVM to dump its heap on OutOfMemory.
REM set FESS_JAVA_OPTS=%FESS_JAVA_OPTS% -XX:+HeapDumpOnOutOfMemoryError
REM The path to the heap dump location, note directory must exists and have enough
REM space for a full heap dump.
REM FESS_JAVA_OPTS=%FESS_JAVA_OPTS% -XX:HeapDumpPath=%FESS_HOME%/logs/heapdump.hprof

REM Disables explicit GC

   * }
   * ```
   *
   * The caller may read the response body with the response's [Response.body] method. To avoid
   * leaking resources callers must [close the response body][ResponseBody] or the response.
   *
   * Note that transport-layer success (receiving a HTTP response code, headers and body) does not
   * necessarily indicate application-layer success: `response` may still indicate an unhappy HTTP
   * response code like 404 or 500.
   *

For those cases, you can use the `jsonable_encoder` to convert your data before passing it to a response:

{* ../../docs_src/response_directly/tutorial001.py hl[6:7,21:22] *}

/// note | Technical Details

You could also use `from starlette.responses import JSONResponse`.

<div class="termy">

```console
$ pip install "fastapi[all]"

---> 100%
```

</div>

...dó cũng bao gồm `uvicorn`, bạn có thể sử dụng như một server để chạy code của bạn.

/// note

Bạn cũng có thể cài đặt nó từng phần.

Đây là những gì bạn có thể sẽ làm một lần duy nhất bạn muốn triển khai ứng dụng của bạn lên production:

```
pip install fastapi
```

Mais il y a encore de nombreuses améliorations et fonctionnalités à venir.

**FastAPI** a un grand avenir devant lui.

Таким образом, вы получите чистую ошибку с кодом состояния HTTP `418` и содержимым JSON:

```JSON
{"message": "Oops! yolo did something. There goes a rainbow..."}
```

/// note | Технические детали

Также можно использовать `from starlette.requests import Request` и `from starlette.responses import JSONResponse`.