Declare the **header parameters** that you need in a **Pydantic model**, and then declare the parameter as `Header`:

{* ../../docs_src/header_param_models/tutorial001_an_py310.py hl[9:14,18] *}

**FastAPI** will **extract** the data for **each field** from the **headers** in the request and give you the Pydantic model you defined.

## Check the Docs { #check-the-docs }

You can see the required headers in the docs UI at `/docs`:

 * certificate.
 *
 * Use of the chain cleaner is necessary to omit unexpected certificates that aren't relevant to
 * the TLS handshake and to extract the trusted CA certificate for the benefit of certificate
 * pinning.
 */
abstract class CertificateChainCleaner {
  @Throws(SSLPeerUnverifiedException::class)
  abstract fun clean(
    chain: List<Certificate>,

        """
        elt = self.element.find('sts:{}'.format(name), _STS_NS)
        return STSElement(self.root_name, elt) if elt is not None else None

    def get_child_text(self, name, strict=True):
        """Extract text of a child element. If strict, and child element is
        not present, raises InvalidXMLError and otherwise returns
        None.

        """
        if strict:
            try:

	var lpVolumeSerialNumber uint32
	var lpFileSystemFlags, lpMaximumComponentLength uint32
	var lpFileSystemNameBuffer, volumeName [260]uint16
	ps := syscall.StringToUTF16Ptr(filepath.VolumeName(path))

	// Extract values safely
	// BOOL WINAPI GetVolumeInformation(
	// _In_opt_  LPCTSTR lpRootPathName,
	// _Out_opt_ LPTSTR  lpVolumeNameBuffer,
	// _In_      DWORD   nVolumeNameSize,
	// _Out_opt_ LPDWORD lpVolumeSerialNumber,

        with:
          name: maven-distributions
          path: maven-dist

      - name: List downloaded files
        shell: bash
        run: ls -la maven-dist

      - name: Extract Maven distribution
        shell: bash
        run: |
          mkdir -p maven-local
          if [ "${{ runner.os }}" = "Windows" ]; then
            unzip maven-dist/apache-maven-*-bin.zip -d maven-local

            PERFORMANCE_DB_USERNAME, gha/gradle/_all/PERFORMANCE_DB_USERNAME
            PERFORMANCE_DB_PASSWORD_TCAGENT, gha/gradle/_all/PERFORMANCE_DB_PASSWORD
      
      - name: Extract database host from URL
        run: |
          # jdbc:mysql://gradle-bt-performance.xyz.eu-central-1.rds.amazonaws.com:3306 -> gradle-bt-performance.xyz.eu-central-1.rds.amazonaws.com

}

func extractMetadata(ctx context.Context, mimesHeader ...textproto.MIMEHeader) (metadata map[string]string, err error) {
	metadata = make(map[string]string)

	for _, hdr := range mimesHeader {
		// Extract all query values.
		err = extractMetadataFromMime(ctx, hdr, metadata)
		if err != nil {
			return nil, err
		}
	}

	// Set content-type to default value if it is not set.

	} `yaml:"ftp"`
	SFTP struct {
		Address       string `yaml:"address"`
		SSHPrivateKey string `yaml:"ssh-private-key"`
	} `yaml:"sftp"`
}

// ServerConfigVersion struct is used to extract the version
type ServerConfigVersion struct {
	Version string `yaml:"version"`
}

// ServerConfigCommon struct for server config common options
type ServerConfigCommon struct {
	RootUser    string `yaml:"rootUser"`

	// Simplify the work of url.Parse() and always send a url with
	if !strings.HasPrefix(hostAddr, "http://") && !strings.HasPrefix(hostAddr, "https://") {
		hostAddr = "//" + hostAddr
	}

	// Parse address to extract host and scheme field
	u, err := url.Parse(hostAddr)
	if err != nil {
		return "", "", err
	}

	addr = u.Host
	scheme = u.Scheme

	// Use the given parameter again if url.Parse()

 * This form extends CreateForm to include fields necessary for updating existing data config entries,
 * including tracking information for optimistic locking and audit trails.
 * Data configs define how to crawl and extract data from databases, CSV files, and other data sources.
 *
 */
public class EditForm extends CreateForm {

    /**
     * Creates a new EditForm instance.
     */
    public EditForm() {
        super();