# Middleware (Проміжний шар)

У **FastAPI** можна додавати middleware (проміжний шар).

"Middleware" — це функція, яка працює з кожним **запитом** перед його обробкою будь-якою конкретною *операцією шляху* (*path operation*), а також з кожною **відповіддю** перед її поверненням.

* Middleware отримує кожен **запит**, що надходить до Вашого застосунку.
* Може виконати певні дії із цим **запитом** або запустити необхідний код.

If one or more drives are offline at the start of a PutObject or NewMultipartUpload operation the object will have additional data
protection bits added automatically to provide the regular safety for these objects up to 50% of the number of drives.
This will allow normal write operations to take place on systems that exceed the write tolerance.

If you pass a "callable" as a dependency in **FastAPI**, it will analyze the parameters for that "callable", and process them in the same way as the parameters for a *path operation function*. Including sub-dependencies.

That also applies to callables with no parameters at all. The same as it would be for *path operation functions* with no parameters.

Then, we can change the dependency "dependable" `common_parameters` from above to the class `CommonQueryParams`:

    "tax": 3.2
}
```

## Resumen

Puedes añadir múltiples parámetros de cuerpo a tu *path operation function*, aunque un request solo puede tener un único cuerpo.

Pero **FastAPI** lo manejará, te dará los datos correctos en tu función, y validará y documentará el esquema correcto en la *path operation*.

También puedes declarar valores singulares para ser recibidos como parte del cuerpo.

import jakarta.annotation.Resource;

/**
 * Service class for managing character mapping operations.
 * <p>
 * This service handles character mapping management including CRUD operations
 * and list retrieval. Character mappings are used for text normalization
 * and character substitution during document processing and search operations.
 * </p>
 */
public class CharMappingService {

    /**

  }

  /**
   * Returns an immutable copy of the provided table.
   *
   * <p>The {@link Table#cellSet()} iteration order of the provided table determines the iteration
   * ordering of all views in the returned table. Note that some views of the original table and the
   * copied table may have different iteration orders. For more control over the ordering, create a

///

Este parámetro no crea ese endpoint / *path operation*, pero declara que la URL `/token` será la que el cliente deberá usar para obtener el token. Esa información se usa en OpenAPI, y luego en los sistemas de documentación interactiva del API.

Pronto también crearemos la verdadera *path operation*.

/// info | Información

| *Type*     | *String* |
| *Required* | *Yes*    |

### DurationSeconds

The duration, in seconds. The value can range from 900 seconds (15 minutes) up to 365 days. If value is higher than this setting, then operation fails. By default, the value is set to 3600 seconds. If no *DurationSeconds* is specified expiry seconds is obtained from *Token*.

| Params        | Value                                              |

    }

    /**
     * Sets the number of bytes remaining to be written in a sequence of write operations.
     *
     * @param remainingBytes the remainingBytes to set
     */
    public void setRemainingBytes(final int remainingBytes) {
        this.remainingBytes = remainingBytes;
    }

    /**
     * Sets the write operation flags.
     *
     * @param writeFlags the writeFlags to set
     */

 * This enum is used to differentiate between various SSO operations,
 * such as metadata requests and logout actions.
 */
public enum SsoResponseType {
    /**
     * Indicates a request for SSO metadata, which is typically used for
     * configuration and discovery in protocols like SAML.
     */
    METADATA,

    /**
     * Indicates a request to perform a logout operation, terminating the
     * user's SSO session.
     */