# Simple OAuth2 con Password y Bearer

Ahora vamos a construir a partir del capítulo anterior y agregar las partes faltantes para tener un flujo de seguridad completo.

## Obtener el `username` y `password`

Vamos a usar las utilidades de seguridad de **FastAPI** para obtener el `username` y `password`.

OAuth2 especifica que cuando se utiliza el "password flow" (que estamos usando), el cliente/usuario debe enviar campos `username` y `password` como form data.

Sebastián Ramírez <******@****.***> 1731896744 +0100

Lee Yesong (이예송) <******@****.***> 1739618352 +0900

Aleksandr Andrukhov <******@****.***> 1733828020 +0300

Sebastián Ramírez <******@****.***> 1731896744 +0100

        return body;
    }

    /**
     * Build a CREATE response body with a single, unrecognized create context.
     * The parser should iterate it but produce an empty contexts array.
     */
    private static byte[] buildCreateBodyWithContext(byte[] fileId, int contextStartOffsetFromHeader) {
        // Base body part size (up to and including CreateContextsLength)

   * failed CAS on base update), the table is initialized to size 2.
   * The table size is doubled upon further contention until
   * reaching the nearest power of two greater than or equal to the
   * number of CPUS. Table slots remain empty (null) until they are
   * needed.
   *
   * A single spinlock ("busy") is used for initializing and

            bb.putShort((short) 15); // tflags
            bb.putShort((short) 0); // tflags high bytes

            // Simple v1 referral
            bb.putShort((short) 1); // version
            bb.putShort((short) 16); // size
            bb.putShort((short) 1); // serverType
            bb.putShort((short) 2); // rflags
            bb.put("\\test\0".getBytes(StandardCharsets.UTF_16LE));

	if ok && len(b.buf) >= size {
		return b
	}
	r := new(Reader)
	r.reset(make([]byte, max(size, minReadBufferSize)), rd)
	return r
}

// NewReader returns a new [Reader] whose buffer has the default size.
func NewReader(rd io.Reader) *Reader {
	return NewReaderSize(rd, defaultBufSize)
}

// Size returns the size of the underlying buffer in bytes.
func (b *Reader) Size() int { return len(b.buf) }

            buffer = new DfsReferralRequestBuffer(path, 3);

            assertEquals(expectedSize, buffer.size());
        }

        @Test
        @DisplayName("Should calculate size for Unicode characters")
        void testSizeWithUnicodeCharacters() {
            // Unicode characters still count as single chars in Java
            String path = "\\\\server\\共享\\路径";
            buffer = new DfsReferralRequestBuffer(path, 3);