# Header Parameter Models { #header-parameter-models }

If you have a group of related **header parameters**, you can create a **Pydantic model** to declare them.

This would allow you to **re-use the model** in **multiple places** and also to declare validations and metadata for all the parameters at once. 😎

/// note

This is supported since FastAPI version `0.115.0`. 🤓

///

///

## Headers duplicados { #duplicate-headers }

Es posible recibir headers duplicados. Eso significa, el mismo header con múltiples valores.

Puedes definir esos casos usando una lista en la declaración del tipo.

Recibirás todos los valores del header duplicado como una `list` de Python.

        // Then
        assertNotNull(result);
        assertEquals(Integer.MAX_VALUE, result.intValue());
        verify(request, times(1)).getOverrideTimeout();
    }

    @Test
    @DisplayName("Test multiple method invocations")
    void testMultipleMethodInvocations() {
        // Given
        when(request.isResponseAsync()).thenReturn(true);
        when(request.size()).thenReturn(100);

     * found in the cache. This method should be called by the loading thread, as well as by threads
     * blocking on the load. Multiple concurrent calls to {@link Cache} lookup methods with the same
     * key on an absent value should result in a single call to either {@code recordLoadSuccess} or
     * {@code recordLoadException} and multiple calls to this method, despite all being served by
     * the results of a single load operation.
     *

        @Test
        @DisplayName("Should handle multiple receives for fragment")
        void testDoSendReceiveFragment_MultipleReceives() throws Exception {
            DcerpcPipeHandle handle = createMockedDcerpcPipeHandle();

            byte[] buf = new byte[50];
            byte[] inB = new byte[100];

            // Setup fragment length requiring multiple receives
            Encdec.enc_uint16le((short) 80, inB, 8);

						key="labels.index_lang"
					/></label>
				<div class="col-lg-5 col-md-8 col-sm-7 col-6">
					<la:select property="lang" styleId="langSearchOption" multiple="true" styleClass="form-control">
						<c:forEach var="item" items="${langItems}">
							<la:option value="${f:u(item.value)}">${f:h(item.label)}</la:option>
						</c:forEach>
					</la:select>
				</div>

package jcifs.smb.compression;

import jcifs.CIFSException;

/**
 * Interface for SMB3 compression services.
 *
 * Provides compression and decompression functionality for SMB3 protocol
 * data transfers with support for multiple compression algorithms.
 */
public interface CompressionService {

    /**
     * Compression algorithm constants matching SMB3 specification.
     */
    public static final int COMPRESSION_NONE = 0x0;

    }

    @Test
    @DisplayName("Test multiple calls to readBytesWireFormat")
    void testMultipleReadBytesWireFormatCalls() throws SMBProtocolDecodingException {
        byte[] buffer = new byte[1024];
        int bufferIndex = 0;

        // Set structure size to 2
        SMBUtil.writeInt2(2, buffer, bufferIndex);

        // Call readBytesWireFormat multiple times
        for (int i = 0; i < 5; i++) {

   *         .addNode(REYKJAVIK)
   *         .build();
   * }
   *
   * <p>Builder instances can be reused; it is safe to call {@link #build} multiple times to build
   * multiple graphs in series. Each new graph contains all the elements of the ones created before
   * it.
   *
   * @since 28.0
   */
  public static class Builder<N, V> {

///

/// warning | Advertencia

Puedes declarar múltiples parámetros `Form` en una *path operation*, pero no puedes también declarar campos `Body` que esperas recibir como JSON, ya que el request tendrá el body codificado usando `application/x-www-form-urlencoded` en lugar de `application/json`.