{* ../../docs_src/request_form_models/tutorial002_an_py39.py hl[12] *}

If a client tries to send some extra data, they will receive an **error** response.

For example, if the client tries to send the form fields:

* `username`: `Rick`
* `password`: `Portal Gun`
* `extra`: `Mr. Poopybutthole`

They will receive an error response telling them that the field `extra` is not allowed:

```json
{
    "detail": [
        {

        // Verify the result
        assertEquals(len, result, "readDataWireFormat should return the length of data read.");

        // Verify that the receive method on the input stream was called exactly once
        verify(mockPipeIn, times(1)).receive(buffer, bufferIndex, len);
    }

    /**
     * Tests the toString method.
     */
    @Test
    void testToString() {

        request.url(), chain.connection(), request.headers()));

    Response response = chain.proceed(request);

    long t2 = System.nanoTime();
    logger.info(String.format("Received response for %s in %.1fms%n%s",
        response.request().url(), (t2 - t1) / 1e6d, response.headers()));

    return response;
  }
}
```

// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

package cmd

import (
	"context"
	"encoding/gob"
	"encoding/hex"
	"encoding/json"

In your WebSocket route you can `await` for messages and send messages.

{* ../../docs_src/websockets/tutorial001_py39.py hl[48:52] *}

You can receive and send binary, text, and JSON data.

## Try it { #try-it }

If your file is named `main.py`, run your application with:

<div class="termy">

```console
$ fastapi dev main.py

 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */
package jcifs.internal.smb1.com;

        void setup() {
            testBlock = new TestServerMessageBlock(mockConfig);
        }

        @Test
        @DisplayName("Test received state")
        void testReceivedState() {
            assertFalse(testBlock.isReceived());

            testBlock.received();
            assertTrue(testBlock.isReceived());

            testBlock.clearReceived();
            assertFalse(testBlock.isReceived());

	// 		// frame will be carried out if no frame is received on the
	// 		// connection. 5 minutes is sufficient time for any idle connection.
	// 		trhttp2.ReadIdleTimeout = 5 * time.Minute
	// 		// PingTimeout is the timeout after which the connection will be closed
	// 		// if a response to Ping is not received.
	// 		trhttp2.PingTimeout = dialTimeout

# Form Data { #form-data }

When you need to receive form fields instead of JSON, you can use `Form`.

/// info

To use forms, first install <a href="https://github.com/Kludex/python-multipart" class="external-link" target="_blank">`python-multipart`</a>.

Make sure you create a [virtual environment](../virtual-environments.md){.internal-link target=_blank}, activate it, and then install it, for example:

```console
$ pip install python-multipart
```

Un `Request` también tiene un `request.receive`, que es una función para "recibir" el cuerpo del request.

El `dict` `scope` y la función `receive` son ambos parte de la especificación ASGI.

Y esas dos cosas, `scope` y `receive`, son lo que se necesita para crear una nueva *Request instance*.