In this case, the original path `/app` would actually be served at `/api/v1/app`.

Even though all your code is written assuming there's just `/app`.

```Python hl_lines="6"
{!../../../docs_src/behind_a_proxy/tutorial001.py!}
```

The word "**server**" is commonly used to refer to both the remote/cloud computer (the physical or virtual machine) and also the program that is running on that machine (e.g. Uvicorn).

Just keep in mind that when you read "server" in general, it could refer to one of those two things.

### OpenAPI

**FastAPI** generates a "schema" with all your API using the **OpenAPI** standard for defining APIs.

#### "Schema"

A "schema" is a definition or description of something. Not the code that implements it, but just an abstract description.

#### API "schema"

By considering these concepts, you will be able to **evaluate and design** the best way to deploy **your own APIs**.

In the next chapters, I'll give you more **concrete recipes** to deploy FastAPI applications.

Documentation = "https://fastapi.tiangolo.com/"
Repository = "https://github.com/tiangolo/fastapi"

[project.optional-dependencies]

standard = [
    "fastapi-cli >=0.0.2",
    # For the test client
    "httpx >=0.23.0",
    # For templates
    "jinja2 >=2.11.2",
    # For forms and file uploads
    "python-multipart >=0.0.7",
    # For UJSONResponse

* 🔧 Fix Ruff configuration unintentionally enabling and re-disabling mccabe complexity check. PR [#10893](https://github.com/tiangolo/fastapi/pull/10893) by [@jiridanek](https://github.com/jiridanek).
* ✅ Re-enable test in `tests/test_tutorial/test_header_params/test_tutorial003.py` after fix in Starlette. PR [#10904](https://github.com/tiangolo/fastapi/pull/10904) by [@ooknimm](https://github.com/ooknimm).

### Docs

![Swagger UI interaction](https://fastapi.tiangolo.com/img/index/index-03-swagger-02.png)

* Alternative API documentation with <a href="https://github.com/Rebilly/ReDoc" class="external-link" target="_blank"><strong>ReDoc</strong></a>.

![ReDoc](https://fastapi.tiangolo.com/img/index/index-06-redoc-02.png)

### Just Modern Python

This example doesn't implement the callback itself (that could be just a line of code), only the documentation part.

!!! tip
    The actual callback is just an HTTP request.

!!! info
    The `app.webhooks` object is actually just an `APIRouter`, the same type you would use when structuring your app with multiple files.

{!../../../docs_src/websockets/tutorial001.py!}
```

!!! note "Technical Details"
    You could also use `from starlette.websockets import WebSocket`.

    **FastAPI** provides the same `WebSocket` directly just as a convenience for you, the developer. But it comes directly from Starlette.

## Await for messages and send messages

In your WebSocket route you can `await` for messages and send messages.

```Python hl_lines="48-52"