assertNotNull(exception.getStackTrace());
        assertTrue(exception.getStackTrace().length > 0);

        // Verify the top of the stack trace points to this test method
        final StackTraceElement topElement = exception.getStackTrace()[0];
        assertEquals("test_stackTrace", topElement.getMethodName());

# Using Dataclasses { #using-dataclasses }

FastAPI is built on top of **Pydantic**, and I have been showing you how to use Pydantic models to declare requests and responses.

But FastAPI also supports using <a href="https://docs.python.org/3/library/dataclasses.html" class="external-link" target="_blank">`dataclasses`</a> the same way:

{* ../../docs_src/dataclasses/tutorial001.py hl[1,7:12,19:20] *}

rgba(0,0,0,.075)}input[type=file].error{color:#b94a48;background:0 0;-webkit-box-shadow:none;box-shadow:none}input[type=file].valid{color:#468847;background:0 0;-webkit-box-shadow:none;box-shadow:none}.form-error{display:block;color:#b94a48;margin-top:5px;margin-bottom:10px;line-height:140%}span.help{color:#999;font-size:90%}input.async-validation,input.validating-server-side,select.async-validation,select.validating-server-side{opacity:.5;background-image:url(data:image/gif;base64,R0lGODlhEAAQA...

 * transforms the file into an efficient format used by OkHttp.
 *
 *
 * The intent is to use this class to update the list periodically by manually running the main
 * method. This should be run from the top-level okhttp directory.
 *
 *
 * The resulting file is used by [PublicSuffixDatabase].
 */
class PublicSuffixListGenerator(
  projectRoot: Path = ".".toPath(),
  val fileSystem: FileSystem = FileSystem.SYSTEM,

code is a great way to give something back to the open source community. Before
you dig right into the code, there are a few guidelines that we need
contributors to follow so that we can have a chance of keeping on top of
things.

Some of the ideas are documented in the [Maven Wiki][maven-wiki]
which might be interesting to read and for further discussion.

Getting Started
---------------

     * This message is shown to users on the authentication page.
     */
    @Size(max = 3000)
    public String notificationLogin;

    /**
     * Notification message displayed on the search top page.
     * This message is shown to users on the main search page.
     */
    @Size(max = 3000)
    public String notificationSearchTop;

    /**
     * System log level for controlling log verbosity.

        assertEquals("{labels.profile.placeholder_confirm_new_password}", FessLabels.LABELS_PROFILE_placeholder_confirm_new_password);

        // Test search related labels
        assertEquals("{labels.top.search}", FessLabels.LABELS_TOP_SEARCH);
        assertEquals("{labels.index_title}", FessLabels.LABELS_index_title);
        assertEquals("{labels.index_form_search_btn}", FessLabels.LABELS_index_form_search_btn);

     * @see Project#isTopProject()
     * @see #getRootDirectory()
     */
    @Nonnull
    Path getTopDirectory();

    /**
     * Gets the root directory of the session, which is the root directory for the top directory project.
     *
     * @return the root directory, never {@code null}
     * @throws IllegalStateException if the root directory could not be found
     * @see #getTopDirectory()
     * @see Project#getRootDirectory()

In most cases you would (and should) have a "termination proxy" handling HTTPS for you on top, this will depend on how you deploy your application, your provider might do this for you, or you might need to set it up yourself.

/// tip

///

## Create a middleware { #create-a-middleware }

To create a middleware you use the decorator `@app.middleware("http")` on top of a function.

The middleware function receives:

* The `request`.
* A function `call_next` that will receive the `request` as a parameter.
    * This function will pass the `request` to the corresponding *path operation*.