# Advanced Middleware { #advanced-middleware }

In the main tutorial you read how to add [Custom Middleware](../tutorial/middleware.md){.internal-link target=_blank} to your application.

And then you also read how to handle [CORS with the `CORSMiddleware`](../tutorial/cors.md){.internal-link target=_blank}.

In this section we'll see how to use other middlewares.

## Adding ASGI middlewares { #adding-asgi-middlewares }

			return errFileAccessDenied
		case isSysErrPathNotFound(err):
			// This is a special case should be handled only for
			// windows, because windows API does not return "not a
			// directory" error message. Handle this specifically
			// here.
			return errFileAccessDenied
		}
	}
	return err
}

// Reliably retries os.RemoveAll if for some reason os.RemoveAll returns
// syscall.ENOTEMPTY (children has files).

/**
 * SMB1 Find Close2 request message.
 *
 * This command is used to close a search handle that was
 * opened by a Trans2 Find First2 request.
 */
public class SmbComFindClose2 extends ServerMessageBlock {

    private final int sid;

    /**
     * Creates a new SMB1 find close request to close a search handle.
     *
     * @param config the CIFS configuration
     * @param sid the search identifier to close

Now let's go back a bit and understand what is all that.

The `password` "flow" is one of the ways ("flows") defined in OAuth2, to handle security and authentication.

OAuth2 was designed so that the backend or API could be independent of the server that authenticates the user.

But in this case, the same **FastAPI** application will handle the API and the authentication.

So, let's review it from that simplified point of view:

pkg syscall, const EBADMSG Errno #67998
pkg syscall, const EPROTO Errno #67998
pkg unicode/utf16, func RuneLen(int32) int #44940
pkg unique, func Make[$0 comparable]($0) Handle[$0] #62483
pkg unique, method (Handle[$0]) Value() $0 #62483

        assertTrue(smbTreeHandle.isSameTree(smbTreeHandle), "isSameTree should return true for the same handle");
        assertFalse(smbTreeHandle.isSameTree(anotherHandle), "isSameTree should return false for a different handle");
    }

    /**
     * Test for isSMB2() method.
     * Verifies that the method returns the correct SMB protocol version status.
     */

			return FileInfoVersions{}, err
		}
		versions, err = xlMeta.ListVersions(volume, path, allParts)
	}
	if err == nil && len(versions) == 0 {
		// This special case is needed to handle len(xlMeta.versions) == 0
		versions = []FileInfo{
			{
				Volume:   volume,
				Name:     path,
				Deleted:  true,
				IsLatest: true,
				ModTime:  timeSentinel1970,
			},
		}
	}
	if err != nil {

        try {
            dataIndexHelper.crawl("test-session-force-stop");
            assertTrue("Should exit quickly when force stopped", true);
        } catch (Exception e) {
            assertTrue("Force stop should handle exceptions quickly", true);
        }
    }

    public void test_crawl_with_short_intervals() {
        try {
            // Test with minimal interval

# Security { #security }

There are many ways to handle security, authentication and authorization.

And it normally is a complex and "difficult" topic.

In many frameworks and systems just handling security and authentication takes a big amount of effort and code (in many cases it can be 50% or more of all the code written).

     */
    boolean generate(String thumbnailId, File outputFile);

    /**
     * Checks if this generator can handle the given document.
     * @param docMap The document map containing metadata.
     * @return True if this generator can handle the document, false otherwise.
     */
    boolean isTarget(Map<String, Object> docMap);

    /**