## Accessing the request body in an exception handler

/// tip

To solve this same problem, it's probably a lot easier to use the `body` in a custom handler for `RequestValidationError` ([Handling Errors](../tutorial/handling-errors.md#use-the-requestvalidationerror-body){.internal-link target=_blank}).

go.exit = process.exit;
WebAssembly.instantiate(fs.readFileSync(process.argv[2]), go.importObject).then((result) => {
	process.on("exit", (code) => { // Node.js exits if no event handler is pending
		if (code === 0 && !go.exited) {
			// deadlock, make Go print error and stack traces
			go._pendingEvent = { id: 0 };
			go._resume();
		}
	});
	return go.run(result.instance);
}).catch((err) => {

	if err != nil {
		t.Fatalf("failed to create HTTP request for Put Object: <ERROR> %v", err)
	}

	// Since `apiRouter` satisfies `http.Handler` it has a ServeHTTP to execute the logic of the handler.
	// Call the ServeHTTP to execute the handler.
	apiRouter.ServeHTTP(rec, req)

	ctx, cancel := context.WithCancel(GlobalContext)
	defer cancel()

	"istio.io/istio/pkg/util/protomarshal"
)

// MessageSlice allows us to marshal slices of protobuf messages like clusters/listeners/routes/endpoints correctly
type MessageSlice []proto.Message

// MarshalJSON handles marshaling of slices of proto messages
func (pSlice MessageSlice) MarshalJSON() ([]byte, error) {
	buffer := bytes.NewBufferString("[")
	sliceLength := len(pSlice)
	for index, msg := range pSlice {

And then mount that under a path.

```Python hl_lines="2-3  23"
{!../../docs_src/wsgi/tutorial001.py!}
```

## Check it

Now, every request under the path `/v1/` will be handled by the Flask application.

And the rest will be handled by **FastAPI**.

If you run it and go to <a href="http://localhost:8000/v1/" class="external-link" target="_blank">http://localhost:8000/v1/</a> you will see the response from Flask:

```txt

    Note over dep: Executar código até o yield
    opt lançar Exceção
        dep -->> handler: lançar Exceção
        handler -->> client: resposta de erro HTTP
    end
    dep ->> operation: Executar dependência, e.g. sessão de BD
    opt raise
        operation -->> dep: Lançar exceção (e.g. HTTPException)
        opt handle
            dep -->> dep: Pode capturar exceções, lançar uma nova HTTPException, lançar outras exceções

	errFatal(err)
	b.Cleanup(grid.Cleanup)
	const responses = 10
	// Create n managers.
	for _, remote := range grid.Managers {
		// Register a single handler which echos the payload.
		errFatal(remote.RegisterStreamingHandler(handlerTest, StreamHandler{
			// Send 10x response.
			Handle: func(ctx context.Context, payload []byte, _ <-chan []byte, out chan<- []byte) *RemoteErr {
				for i := 0; i < responses; i++ {

import jcifs.internal.util.SMBUtil;


/**
 *
 */
public class FileFsFullSizeInformation implements AllocInfo, FileSystemInformation, Decodable {

    private long alloc; // Also handles SmbQueryFSSizeInfo
    private long free;
    private int sectPerAlloc;
    private int bytesPerSect;


    /**
     * {@inheritDoc}
     *

 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
package org.apache.maven.repository;

import org.apache.maven.artifact.handler.ArtifactHandler;

/**
 * Assists unit testing.
 *
 */
@Deprecated
class TestArtifactHandler implements ArtifactHandler {

    private String type;

    private String extension;

import jcifs.internal.SMBProtocolDecodingException;
import jcifs.internal.util.SMBUtil;


/**
 *
 */
public class FileFsSizeInformation implements AllocInfo {

    private long alloc; // Also handles SmbQueryFSSizeInfo
    private long free;
    private int sectPerAlloc;
    private int bytesPerSect;


    /**
     * {@inheritDoc}
     *