# 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 (default) process, is as follows.

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

A middleware doesn't have to be made for FastAPI or Starlette to work, as long as it follows the ASGI spec.

In general, ASGI middlewares are classes that expect to receive an ASGI app as the first argument.

So, in the documentation for third-party ASGI middlewares they will probably tell you to do something like:

    /**
     * Proxy server port
     */
    private int port;

    /**
     * Type of the proxy
     */
    private String protocol;

    /**
     * The non-proxy hosts. Follows Java system property format: <code>*.foo.com|localhost</code>.
     */
    private String nonProxyHosts;

    /**
     * For NTLM proxies, specifies the NTLM host.
     */
    private String ntlmHost;

    /**

   * which it is unnecessary to programmatically distinguish between exception types or to extract
   * other information from the exception instance.
   *
   * <p>Exceptions from {@code Future.get} are treated as follows:
   *
   * <ul>
   *   <li>Any {@link ExecutionException} has its <i>cause</i> wrapped in an {@code X} if the cause
   *       is a checked exception, an {@link UncheckedExecutionException} if the cause is a {@code

**FastAPI** will recognize each of them and take the data from the correct place.

{* ../../docs_src/body/tutorial004_py310.py hl[16] *}

The function parameters will be recognized as follows:

* If the parameter is also declared in the **path**, it will be used as a path parameter.
* If the parameter is of a **singular type** (like `int`, `float`, `str`, `bool`, etc) it will be interpreted as a **query** parameter.

   * which it is unnecessary to programmatically distinguish between exception types or to extract
   * other information from the exception instance.
   *
   * <p>Exceptions from {@code Future.get} are treated as follows:
   *
   * <ul>
   *   <li>Any {@link ExecutionException} has its <i>cause</i> wrapped in an {@code X} if the cause
   *       is a checked exception, an {@link UncheckedExecutionException} if the cause is a {@code

                        properties:
                          authority:
                            description: 'HTTP Authority values are case-sensitive
                              and formatted as follows: - `exact: "value"` for exact
                              string match - `prefix: "value"` for prefix-based match

  public void testExplicit_withDuplicates() {
    assertThrows(IllegalArgumentException.class, () -> Ordering.explicit(1, 2, 3, 4, 2));
  }

  // A more limited test than the one that follows, but this one uses the
  // actual public API.
  @J2ktIncompatible // Ordering.arbitrary
  public void testArbitrary_withoutCollisions() {
    List<Object> list = Lists.newArrayList();
    for (int i = 0; i < 50; i++) {

  public void testExplicit_withDuplicates() {
    assertThrows(IllegalArgumentException.class, () -> Ordering.explicit(1, 2, 3, 4, 2));
  }

  // A more limited test than the one that follows, but this one uses the
  // actual public API.
  @J2ktIncompatible // Ordering.arbitrary
  public void testArbitrary_withoutCollisions() {
    List<Object> list = Lists.newArrayList();
    for (int i = 0; i < 50; i++) {

			Object: object,
		}
	}

	if opts.DeletePrefix {
		if opts.Expiration.Expire {
			// Expire all versions expiration must still verify the state() on disk
			// via a getObjectInfo() call as follows, any read quorum issues we
			// must not proceed further for safety reasons. attempt a MRF heal
			// while we see such quorum errors.
			goi, _, gerr := er.getObjectInfoAndQuorum(ctx, bucket, object, opts)