return string;
  }

  /**
   * Returns the escaped form of the given character, or {@code null} if this character does not
   * need to be escaped. If an empty array is returned, this effectively strips the input character
   * from the resulting text.
   *
   * <p>If the character does not need to be escaped, this method should return {@code null}, rather

        // Directory leasing requires SMB 3.0 or higher
        // MS-SMB2: Level 2 leasing (which includes directory leasing) is only supported in SMB 3.0+
        // We'll validate this when we actually need to use the session

        // Request base lease
        Smb2LeaseKey leaseKey = baseLeaseManager.requestLease(directoryPath, requestedState);

        // Create directory cache entry

# JSON with Bytes as Base64 { #json-with-bytes-as-base64 }

If your app needs to receive and send JSON data, but you need to include binary data in it, you can encode it as base64.

## Base64 vs Files { #base64-vs-files }

Consider first if you can use [Request Files](../tutorial/request-files.md) for uploading binary data and [Custom Response - FileResponse](./custom-response.md#fileresponse--fileresponse-) for sending binary data, instead of encoding it in JSON.

]
```

These are **JavaScript** objects, not strings, so you can't pass them from Python code directly.

* [Graphene](https://graphene-python.org/)
    * With [starlette-graphene3](https://github.com/ciscorn/starlette-graphene3)

## GraphQL with Strawberry { #graphql-with-strawberry }

If you need or want to work with **GraphQL**, [**Strawberry**](https://strawberry.rocks/) is the **recommended** library as it has the design closest to **FastAPI's** design, it's all based on **type annotations**.

    Class<T> getType();

    /**
     * Creates a copy of the data suitable for storage in the cache. The original data to store can be mutated after the
     * cache is populated but the state of the cache must not change so we need to make a copy.
     *
     * @param data The data to store in the cache, must not be {@code null}.
     * @return The data being stored in the cache, never {@code null}.
     */
    T intoCache(T data);

    /**

# Extending OpenAPI { #extending-openapi }

There are some cases where you might need to modify the generated OpenAPI schema.

In this section you will see how.

## The normal process { #the-normal-process }

The normal (default) process, is as follows.

A `FastAPI` application (instance) has an `.openapi()` method that is expected to return the OpenAPI schema.

        withModule<RemoveXmlApisRule>("xalan:xalan")
        withModule<RemoveXmlApisRule>("jaxen:jaxen")

        // We only need "failureaccess" of Guava's dependencies
        applyRule<KeepDependenciesByNameRule>("com.google.guava:guava", setOf("failureaccess"))

        // We only need a few utility classes of this module
        applyRule<DependencyRemovalByNameRule>("jcifs:jcifs", setOf("servlet-api"))

        assertEquals(0, transaction.pad(8)); // Already aligned
        assertEquals(3, transaction.pad(1)); // Need 3 bytes to align to 4
        assertEquals(2, transaction.pad(2)); // Need 2 bytes to align to 4
        assertEquals(1, transaction.pad(3)); // Need 1 byte to align to 4
    }

    @Test
    @DisplayName("Test getPadding method")
    void testGetPadding() {

# OpenAPI

There are several utilities to handle OpenAPI.