This is because FastAPI uses this `root_path` to create the default `server` in OpenAPI with the URL provided by `root_path`.

## Additional servers

!!! warning
    This is a more advanced use case. Feel free to skip it.

By default, **FastAPI** will create a `server` in the OpenAPI schema with the URL for the `root_path`.

          pip install -r requirements-tests.txt
      - name: Run source distribution tests
        run: |
          cd dist/fastapi*/
          bash scripts/test.sh
      - name: Build wheel distribution
        run: |
          cd dist
          pip wheel --no-deps fastapi*.tar.gz
      - name: Dump GitHub context
        env:
          GITHUB_CONTEXT: ${{ toJson(github) }}

Dans les versions précédentes de Javascript NodeJS / Navigateur, vous auriez utilisé des "callbacks". Menant potentiellement à ce que l'on appelle <a href="http://callbackhell.com/" class="external-link" target="_blank">le "callback hell"</a>.


## Coroutines

* ♻ Internal small refactor, move `operation_id` parameter position in delete method for consistency with the code. PR [#4474](https://github.com/tiangolo/fastapi/pull/4474) by [@hiel](https://github.com/hiel).
* 🔧 Update sponsors, disable ImgWhale. PR [#5338](https://github.com/tiangolo/fastapi/pull/5338) by [@tiangolo](https://github.com/tiangolo).

## 0.81.0

### Features

    Temporarily adopting this point of view (of the *external developer*) can help you feel like it's more obvious where to put the parameters, the Pydantic model for the body, for the response, etc. for that *external API*.

### Create a callback `APIRouter`

* `^`: starts with the following characters, doesn't have characters before.
* `fixedquery`: has the exact value `fixedquery`.
* `$`: ends there, doesn't have any more characters after `fixedquery`.

If you feel lost with all these **"regular expression"** ideas, don't worry. They are a hard topic for many people. You can still do a lot of stuff without needing regular expressions yet.

In previous versions of NodeJS / Browser JavaScript, you would have used "callbacks". Which leads to <a href="http://callbackhell.com/" class="external-link" target="_blank">callback hell</a>.

## Coroutines

For this reason it's common to provide them in environment variables that are read by the application.

## Environment Variables

!!! tip
    If you already know what "environment variables" are and how to use them, feel free to skip to the next section below.

!!! warning
    These are very technical details about the standards **JSON Schema** and **OpenAPI**.

    If the ideas above already work for you, that might be enough, and you probably don't need these details, feel free to skip them.

Before OpenAPI 3.1.0, OpenAPI used an older and modified version of **JSON Schema**.

JSON Schema didn't have `examples`, so OpenAPI added it's own `example` field to its own modified version.

En versiones anteriores de NodeJS / Browser JavaScript, habrías utilizado "callbacks". Lo que conduce a <a href="http://callbackhell.com/" class="external-link" target="_blank">callback hell</a>.

## Coroutines