# Body - Fields { #body-fields }

The same way you can declare additional validation and metadata in *path operation function* parameters with `Query`, `Path` and `Body`, you can declare validation and metadata inside of Pydantic models using Pydantic's `Field`.

## Import `Field` { #import-field }

First, you have to import it:

{* ../../docs_src/body_fields/tutorial001_an_py310.py hl[4] *}


/// warning

 * under the License.
 */
package org.apache.maven.repository.legacy.metadata;

import java.util.List;

import org.apache.maven.artifact.Artifact;
import org.apache.maven.artifact.repository.ArtifactRepository;
import org.apache.maven.artifact.versioning.ArtifactVersion;

/**
 * Provides some metadata operations, like querying the remote repository for a list of versions available for an
 * artifact.
 *

Connected to localhost.
sftp> ls runner/
chunkdocs  testdir
```

Following example shows how to download an object locally via `sftp` client:

```
sftp> get runner/chunkdocs/metadata metadata
Fetching /runner/chunkdocs/metadata to metadata
metadata                                                                                                                                                                       100%  226    16.6KB/s   00:00
sftp>

func (fi FileInfo) IsCompressed() bool {
	_, ok := fi.Metadata[ReservedMetadataPrefix+"compression"]
	return ok
}

// InlineData returns true if object contents are inlined alongside its metadata.
func (fi FileInfo) InlineData() bool {
	_, ok := fi.Metadata[ReservedMetadataPrefixLower+"inline-data"]
	// Earlier MinIO versions didn't reset "x-minio-internal-inline-data"
	// from fi.Metadata when the object was tiered. So, tiered objects

## Metadatos OpenAPI - Documentación { #openapi-metadata-docs }

Para agregar metadatos a tu esquema de OpenAPI, incluyendo una licencia, versión, contacto, etc, lee la documentación para [Tutorial - Metadatos y URLs de Documentación](../tutorial/metadata.md){.internal-link target=_blank}.

## URL Personalizada de OpenAPI { #openapi-custom-url }

	maps.Copy(metadata, encMetadata)

	// Ensure that metadata does not contain sensitive information
	crypto.RemoveSensitiveEntries(metadata)

	if isCompressible(r.Header, object) {
		// Storing the compression metadata.
		metadata[ReservedMetadataPrefix+"compression"] = compressionAlgorithmV2
	}

	opts, err := putOptsFromReq(ctx, r, bucket, object, metadata)
	if err != nil {

package org.apache.maven.artifact.repository.metadata;

import org.apache.maven.artifact.Artifact;
import org.apache.maven.artifact.ArtifactUtils;
import org.apache.maven.artifact.repository.ArtifactRepository;
import org.apache.maven.artifact.versioning.ArtifactVersion;
import org.apache.maven.artifact.versioning.Restriction;
import org.apache.maven.artifact.versioning.VersionRange;

/**
 * Metadata for the artifact directory of the repository.

	}

	// if storageClass is standard no need to save it as part of metadata.
	if userDefined[xhttp.AmzStorageClass] == storageclass.STANDARD {
		delete(userDefined, xhttp.AmzStorageClass)
	}

	// Fill all the necessary metadata.
	// Update `xl.meta` content on each disks.
	for index := range partsMetadata {
		partsMetadata[index].Metadata = userDefined
		partsMetadata[index].Size = n

package disk

import (
	"os"
	"syscall"

	"golang.org/x/sys/unix"
)

// Fdatasync - fdatasync() is similar to fsync(), but does not flush modified metadata
// unless that metadata is needed in order to allow a subsequent data retrieval
// to  be  correctly  handled.   For example, changes to st_atime or st_mtime
// (respectively, time of last access and time of last modification; see inode(7))

					return
				}
			}
		case "Metadata":
			var zb0003 uint32
			zb0003, err = dc.ReadArrayHeader()
			if err != nil {
				err = msgp.WrapError(err, "Metadata")
				return
			}
			if cap(z.Metadata) >= int(zb0003) {
				z.Metadata = (z.Metadata)[:zb0003]
			} else {
				z.Metadata = make([]BatchJobKV, zb0003)
			}
			for za0002 := range z.Metadata {
				err = z.Metadata[za0002].DecodeMsg(dc)