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

!!! tip
    Notice that you are not passing the router itself (`invoices_callback_router`) to `callback=`, but the attribute `.routes`, as in `invoices_callback_router.routes`.

### Check the docs

Now you can start your app and go to <a href="http://127.0.0.1:8000/docs" class="external-link" target="_blank">http://127.0.0.1:8000/docs</a>.

import okhttp3.Response
import okhttp3.Route

class RecordingOkAuthenticator(
  val credential: String?,
  val scheme: String?,
) : Authenticator {
  val responses = mutableListOf<Response>()
  val routes = mutableListOf<Route>()

  fun onlyResponse() = responses.single()

  fun onlyRoute() = routes.single()

  @Throws(IOException::class)
  override fun authenticate(
    route: Route?,
    response: Response,

	}{
		{
			name: "empty-gateway",
		},
		{
			name: "istio-gateway-http-route-prefix",
		},
		{
			name: "k8s-gateway-http-route-path-prefix",
		},
	}
	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			gotOut := &bytes.Buffer{}
			cw := &ConfigWriter{Stdout: gotOut}
			cd, _ := os.ReadFile(fmt.Sprintf("testdata/routes/%s/configdump.json", tt.name))
			if err := cw.Prime(cd); err != nil {

	// Add server metrics router
	registerMetricsRouter(router)

	// Add STS router always.
	registerSTSRouter(router)

	// Add KMS router
	registerKMSRouter(router)

	// Add API router
	registerAPIRouter(router)

	router.Use(globalMiddlewares...)

	return router, nil

 "configs": [
  {
   "@type": "type.googleapis.com/envoy.admin.v3.RoutesConfigDump",
   "static_route_configs": [
    {
     "route_config": {
      "@type": "type.googleapis.com/envoy.config.route.v3.RouteConfiguration",
      "virtual_hosts": [
       {
        "name": "backend",
        "domains": [
         "*"
        ],
        "routes": [
         {
          "match": {
           "prefix": "/stats/prometheus"
          },

      pingIntervalMillis = pingIntervalMillis,
      retryOnConnectionFailure = retryOnConnectionFailure,
      user = user,
      routePlanner = routePlanner,
      route = route,
      routes = routes,
      attempt = attempt,
      tunnelRequest = tunnelRequest,
      connectionSpecIndex = connectionSpecIndex,
      isTlsFallback = isTlsFallback,
    )
  }

🔜 ⚙️ 🔢 `callbacks` *👆 🛠️ ➡ 🛠️ 👨‍🎨* 🚶‍♀️ 🔢 `.routes` (👈 🤙 `list` 🛣/*➡ 🛠️*) ⚪️➡️ 👈 ⏲ 📻:

```Python hl_lines="35"
{!../../../docs_src/openapi_callbacks/tutorial001.py!}
```

!!! tip
    👀 👈 👆 🚫 🚶‍♀️ 📻 ⚫️ (`invoices_callback_router`) `callback=`, ✋️ 🔢 `.routes`, `invoices_callback_router.routes`.

### ✅ 🩺

至此，在上文创建的回调路由里就包含了*回调路径操作*（外部开发者要在外部 API 中实现）。

现在使用 API *路径操作装饰器*的参数 `callbacks`，从回调路由传递属性 `.routes`（实际上只是路由/路径操作的**列表**）：

```Python hl_lines="36"
{!../../../docs_src/openapi_callbacks/tutorial001.py!}
```

!!! tip "提示"

    注意，不能把路由本身（`invoices_callback_router`）传递给 `callback=`，要传递 `invoices_callback_router.routes` 中的 `.routes` 属性。

### 查看文档

  val failedRoutes: Set<Route>
    @Synchronized get() = _failedRoutes.toSet()

  /** Records a failure connecting to [failedRoute]. */
  @Synchronized fun failed(failedRoute: Route) {
    _failedRoutes.add(failedRoute)
  }

  /** Records success connecting to [route]. */
  @Synchronized fun connected(route: Route) {
    _failedRoutes.remove(route)
  }

		t.Fatalf("Failed to create Comparator: %v", err)
	}
	err = comparator.Diff()
	if err != nil {
		t.Errorf("Unexpected error during diff: %v", err)
	}

	expected := []string{"Clusters Match", "Listeners Match", "Routes Match"}
	for _, exp := range expected {
		if !bytes.Contains(outputBuffer.Bytes(), []byte(exp)) {
			t.Errorf("Expected %s, but it was not found", exp)
		}
	}
}