## The normal **FastAPI** app

Let's first see how the normal API app would look like before adding the callback.

It will have a *path operation* that will receive an `Invoice` body, and a query parameter `callback_url` that will contain the URL for the callback.

This part is pretty normal, most of the code is probably already familiar to you:

```Python hl_lines="9-13  36-53"
{!../../../docs_src/openapi_callbacks/tutorial001.py!}
```

!!! tip

        Map artifactMap = project.getArtifactMap();

        assertNotNull( artifactMap, "artifact-map should not be null." );
        assertEquals( 1, artifactMap.size(), "artifact-map should contain 1 element." );

        Artifact artifact = (Artifact) artifactMap.get( key );

        assertNotNull( artifact, "dependency artifact not found in map." );

then an `api/next` file with the line

    pkg net/http, function F #12345

should have a corresponding file named `doc/next/6-stdlib/99-minor/net/http/12345.md`.
At a minimum, that file should contain either a full sentence or a TODO,
ideally referring to a person with the responsibility to complete the note.

Use the following forms in your markdown:

 * provides symbol names from binary libraries in Standalone mode, which the Standalone declaration provider does not contain (to avoid
 * stub-indexing binary libraries). And in general, querying the symbol names provider might be faster since its sets are cached, which is

            display = ParameterDisplay.PROMPT,
            allowEmpty = false,
            description = "The name of the test to run, as should be passed to --tests. Can't contain spaces since there are problems with Teamcity's escaping, you can use * instead."
        )
        text(
            testJvmVersionParameter,
            JvmVersion.java11.major.toString(),

			"status",
		)
	if errors.IsNotFound(err) {
		return nil
	}
	return err
}

// Get any IPs currently assigned to the Pod.
//
// If 'PodIPs' exists, it is preferred (and should be guaranteed to contain the address in 'PodIP'),
// otherwise fallback to 'PodIP'.
//
// Note that very early in the pod's lifecycle (before all the node CNI plugin invocations finish)

                        if (!nonInterfaces.isEmpty()) {
                            throw new IllegalArgumentException(
                                    "The Typed annotation must contain only interfaces but the following types are not: "
                                            + nonInterfaces);
                        }
                        return value;