And those Python files are included/injected in the documentation when generating the site.

### Docs for tests

Most of the tests actually run against the example source files in the documentation.

This helps to make sure that:

* The documentation is up-to-date.
* The documentation examples can be run as is.

In this example we'll create a temporary database only for the tests.

## File structure

We create a new file at `sql_app/tests/test_sql_app.py`.

So the new file structure looks like:

``` hl_lines="9-11"
.
└── sql_app
    ├── __init__.py
    ├── crud.py
    ├── database.py
    ├── main.py
    ├── models.py
    ├── schemas.py
    └── tests
        ├── __init__.py
        └── test_sql_app.py
```

!!! tip
    If you want to call `async` functions in your tests apart from sending requests to your FastAPI application (e.g. asynchronous database functions), have a look at the [Async Tests](../advanced/async-tests.md){.internal-link target=_blank} in the advanced tutorial.

## Separating tests

In a real application, you probably would have your tests in a different file.

## Upgrading the FastAPI versions

You should add tests for your app.

With **FastAPI** it's very easy (thanks to Starlette), check the docs: [Testing](../tutorial/testing.md){.internal-link target=_blank}

After you have tests, then you can upgrade the **FastAPI** version to a more recent one, and make sure that all your code is working correctly by running your tests.

Après avoir effectué des tests, vous pouvez mettre à jour la version **FastAPI** vers une version plus récente, et vous assurer que tout votre code fonctionne correctement en exécutant vos tests.

Si tout fonctionne, ou après avoir fait les changements nécessaires, et que tous vos tests passent, vous pouvez
épingler votre version de `fastapi` à cette nouvelle version récente.

* *Worker* **Celery** pouvant importer et utiliser les modèles et le code du reste du backend.

# Testing Events: startup - shutdown

When you need your event handlers (`startup` and `shutdown`) to run in your tests, you can use the `TestClient` with a `with` statement:

```Python hl_lines="9-12  20-24"
{!../../../docs_src/app_testing/tutorial003.py!}

* **Alembic**-Migrationen.
* **CORS** (Cross Origin Resource Sharing).
* **Celery**-Worker, welche Modelle und Code aus dem Rest des Backends selektiv importieren und verwenden können.

<div style="text-align: right; margin-right: 10%;">Kabir Khan - <strong>Microsoft</strong> <a href="https://github.com/tiangolo/fastapi/pull/26" target="_blank"><small>(ref)</small></a></div>

---

"_We adopted the **FastAPI** library to spawn a **REST** server that can be queried to obtain **predictions**. [for Ludwig]_"

<div style="text-align: right; margin-right: 10%;">Kabir Khan - <strong>Microsoft</strong> <a href="https://github.com/tiangolo/fastapi/pull/26" target="_blank"><small>(ref)</small></a></div>

---

"_Мы использовали библиотеку **FastAPI** для создания сервера **REST**, к которому можно делать запросы для получения **прогнозов**. [для Ludwig]_"