from typing import Annotated

from fastapi import FastAPI, File, UploadFile

app = FastAPI()


@app.post("/files/")
async def create_file(file: Annotated[bytes | None, File()] = None):
    if not file:
        return {"message": "No file sent"}
    else:
        return {"file_size": len(file)}


@app.post("/uploadfile/")
async def create_upload_file(file: UploadFile | None = None):
    if not file:

from typing import Annotated

from fastapi import FastAPI, File, UploadFile

app = FastAPI()


@app.post("/files/")
async def create_file(file: Annotated[bytes, File()]):
    return {"file_size": len(file)}


@app.post("/uploadfile/")
async def create_upload_file(file: UploadFile):

        return is_pv1_scalar_sequence_field(field)

    def is_bytes_field(field: ModelField) -> bool:
        return lenient_issubclass(field.type_, bytes)

    def is_bytes_sequence_field(field: ModelField) -> bool:
        return field.shape in sequence_shapes and lenient_issubclass(field.type_, bytes)  # type: ignore[attr-defined]

    def copy_field_info(*, field_info: FieldInfo, annotation: Any) -> FieldInfo:
        return copy(field_info)

```

In this example, we didn't declare any Pydantic model. In fact, the request body is not even <abbr title="converted from some plain format, like bytes, into Python objects">parsed</abbr> as JSON, it is read directly as `bytes`, and the function `magic_data_reader()` would be in charge of parsing it in some way.

Nevertheless, we can declare the expected schema for the request body.

// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package waypoint

import (
	"bytes"
	"context"
	"fmt"
	"os"
	"strings"
	"testing"

	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
	gateway "sigs.k8s.io/gateway-api/apis/v1"

	"istio.io/api/label"
	"istio.io/istio/istioctl/pkg/cli"

  fun trailers(): Headers = trailersFn()

  /**
   * Peeks up to [byteCount] bytes from the response body and returns them as a new response
   * body. If fewer than [byteCount] bytes are in the response body, the full response body is
   * returned. If more than [byteCount] bytes are in the response body, the returned value
   * will be truncated to [byteCount] bytes.
   *
   * It is an error to call this method after the body has been consumed.

								appendFieldsToMap(reflectValue.Field(i))
							}
						}
					}
				}
			}

			appendFieldsToMap(reflect.ValueOf(value))
		}
	}

	name := make([]byte, 0, 10)

	for _, v := range []byte(expr.SQL) {
		if v == '@' && !inName {
			inName = true
			name = name[:0]
		} else if v == ' ' || v == ',' || v == ')' || v == '"' || v == '\'' || v == '`' || v == '\r' || v == '\n' || v == ';' {

	}

	return "", fmt.Errorf("no valid networks found in %s", confDir)
}

// insertCNIConfig will append newCNIConfig to existingCNIConfig
func insertCNIConfig(newCNIConfig, existingCNIConfig []byte) ([]byte, error) {
	var istioMap map[string]any
	err := json.Unmarshal(newCNIConfig, &istioMap)
	if err != nil {
		return nil, fmt.Errorf("error loading Istio CNI config (JSON error): %v", err)
	}

		clientPingInterval: parent.clientPingInterval,
	}
}

// roundtrip performs a roundtrip, returning the first response.
// This cannot be used concurrently.
func (m *muxClient) roundtrip(h HandlerID, req []byte) ([]byte, error) {
	if m.init {
		return nil, errors.New("mux client already used")
	}
	m.init = true
	m.singleResp = true
	msg := message{
		Op:         OpRequest,
		MuxID:      m.MuxID,
		Handler:    h,

```go
package main

import (
	"fmt"

	"github.com/smallnest/ringbuffer"
)

func main() {
	rb := ringbuffer.New(1024)

	// write
	rb.Write([]byte("abcd"))
	fmt.Println(rb.Length())
	fmt.Println(rb.Free())

	// read
	buf := make([]byte, 4)
	rb.Read(buf)
	fmt.Println(string(buf))
}
```

It is possible to use an existing buffer with by replacing `New` with `NewBuffer`.