timothy <******@****.***> 1733829888 +0900

# Testing { #testing }

Thanks to <a href="https://www.starlette.io/testclient/" class="external-link" target="_blank">Starlette</a>, testing **FastAPI** applications is easy and enjoyable.

It is based on <a href="https://www.python-httpx.org" class="external-link" target="_blank">HTTPX</a>, which in turn is designed based on Requests, so it's very familiar and intuitive.

Valentyn <******@****.***> 1740751939 -0500

# Testing

Gracias a <a href="https://www.starlette.io/testclient/" class="external-link" target="_blank">Starlette</a>, escribir pruebas para aplicaciones de **FastAPI** es fácil y agradable.

Está basado en <a href="https://www.python-httpx.org" class="external-link" target="_blank">HTTPX</a>, que a su vez está diseñado basado en Requests, por lo que es muy familiar e intuitivo.

# Testing a Database { #testing-a-database }

You can study about databases, SQL, and SQLModel in the <a href="https://sqlmodel.tiangolo.com/" class="external-link" target="_blank">SQLModel docs</a>. 🤓

There's a mini <a href="https://sqlmodel.tiangolo.com/tutorial/fastapi/" class="external-link" target="_blank">tutorial on using SQLModel with FastAPI</a>. ✨

# Testing Events: lifespan and startup - shutdown { #testing-events-lifespan-and-startup-shutdown }

When you need `lifespan` to run in your tests, you can use the `TestClient` with a `with` statement:

{* ../../docs_src/app_testing/tutorial004.py hl[9:15,18,27:28,30:32,41:43] *}


You can read more details about the ["Running lifespan in tests in the official Starlette documentation site."](https://www.starlette.io/lifespan/#running-lifespan-in-tests)

{* ../../docs_src/app_testing/tutorial002.py hl[27:31] *}

/// note | Nota

Para más detalles, revisa la documentación de Starlette sobre <a href="https://www.starlette.io/testclient/#testing-websocket-sessions" class="external-link" target="_blank">probando sesiones WebSocket</a>.

Sebastián Ramírez <******@****.***> 1735583217 +0000

# Testing WebSockets { #testing-websockets }

You can use the same `TestClient` to test WebSockets.

For this, you use the `TestClient` in a `with` statement, connecting to the WebSocket:

{* ../../docs_src/app_testing/tutorial002.py hl[27:31] *}

/// note

For more details, check Starlette's documentation for <a href="https://www.starlette.io/testclient/#testing-websocket-sessions" class="external-link" target="_blank">testing WebSockets</a>.

# Testing Dependencies with Overrides { #testing-dependencies-with-overrides }

## Overriding dependencies during testing { #overriding-dependencies-during-testing }

There are some scenarios where you might want to override a dependency during testing.

You don't want the original dependency to run (nor any of the sub-dependencies it might have).