{* ../../docs_src/custom_request_and_route/tutorial002.py hl[16:18] *}

## Custom `APIRoute` class in a router { #custom-apiroute-class-in-a-router }

You can also set the `route_class` parameter of an `APIRouter`:

{* ../../docs_src/custom_request_and_route/tutorial003.py hl[26] *}

    - topic_repos: ../en/data/topic_repos.yml
  redirects:
    redirect_maps:
      deployment/deta.md: deployment/cloud.md
      advanced/graphql.md: how-to/graphql.md
      advanced/custom-request-and-route.md: how-to/custom-request-and-route.md
      advanced/conditional-openapi.md: how-to/conditional-openapi.md
      advanced/extending-openapi.md: how-to/extending-openapi.md
      advanced/testing-database.md: how-to/testing-database.md

For example:

```Python
app.add_middleware(MiddlewareA)
app.add_middleware(MiddlewareB)
```

This results in the following execution order:

* **Request**: MiddlewareB → MiddlewareA → route

* **Response**: route → MiddlewareA → MiddlewareB

This stacking behavior ensures that middlewares are executed in a predictable and controllable order.

## Other middlewares { #other-middlewares }

    ```kotlin
      private val client = OkHttpClient.Builder()
          .authenticator(object : Authenticator {
            @Throws(IOException::class)
            override fun authenticate(route: Route?, response: Response): Request? {
              if (response.request.header("Authorization") != null) {
                return null // Give up, we've already attempted to authenticate.
              }

      "ResponseBodyEnd",
      "ConnectionReleased",
      "CallEnd",
    )
  }

  @Test
  fun sseReauths() {
    client =
      client
        .newBuilder()
        .authenticator { route, response ->
          response.request
            .newBuilder()
            .header("Authorization", "XYZ")
            .build()
        }.build()
    server.enqueue(
      MockResponse(

///

## Await for messages and send messages { #await-for-messages-and-send-messages }

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

{* ../../docs_src/websockets/tutorial001.py hl[48:52] *}

You can receive and send binary, text, and JSON data.

## Try it { #try-it }

So, in a URL like:

```
https://example.com/items/foo
```

...the path would be:

```
/items/foo
```

/// info

A "path" is also commonly called an "endpoint" or a "route".

///

While building an API, the "path" is the main way to separate "concerns" and "resources".

#### Operation { #operation }

"Operation" here refers to one of the HTTP "methods".

One of:

It is a plug-in for many frameworks (and there's a plug-in for Starlette too).

The way it works is that you write the definition of the schema using YAML format inside the docstring of each function handling a route.

And it generates OpenAPI schemas.

That's how it works in Flask, Starlette, Responder, etc.

But then, we have again the problem of having a micro-syntax, inside of a Python string (a big YAML).

* `dependencies`: to include ✨ router-level dependencies ✨ that apply to all the *path operations* in a router. Up to now, this was only possible with `include_router`.
* `callbacks`: OpenAPI callbacks that apply to all the *path operations* in this router.
* `deprecated`: to mark all the *path operations* in a router as deprecated.

	hip, errCode := extractHealInitParams(mux.Vars(r), r.Form, r.Body)
	if errCode != ErrNone {
		writeErrorResponseJSON(ctx, w, errorCodes.ToAPIErr(errCode), r.URL)
		return
	}

	// Analyze the heal token and route the request accordingly
	token, _, success := proxyRequestByToken(ctx, w, r, hip.clientToken, false)
	if success {
		return
	}
	hip.clientToken = token