[providers]
  [providers.file]
    filename = "routes.toml"
```

This tells Traefik to listen on port 9999 and to use another file `routes.toml`.

/// tip

We are using port 9999 instead of the standard HTTP port 80 so that you don't have to run it with admin (`sudo`) privileges.

///

Now create that other file `routes.toml`:

```TOML hl_lines="5  12  20"
[http]
  [http.middlewares]

    }

    OkHttpClient client = builder.build();

    sendRequest(client, "https://valid-isrgrootx1.letsencrypt.org/robots.txt");

    try {
      sendRequest(client, "https://google.com/robots.txt");
      if (androidMorEarlier) {
        // will pass with default CAs on N or later
        fail();
      }
    } catch (SSLHandshakeException sslhe) {

{* ../../docs_src/openapi_callbacks/tutorial001.py hl[35] *}

/// tip | Consejo

Observa que no estás pasando el router en sí (`invoices_callback_router`) a `callback=`, sino el atributo `.routes`, como en `invoices_callback_router.routes`.

///

### Revisa la documentación

& 👈 🔢 `get_openapi()` 📨 🔢:

* `title`: 🗄 📛, 🎦 🩺.
* `version`: ⏬ 👆 🛠️, ✅ `2.5.0`.
* `openapi_version`: ⏬ 🗄 🔧 ⚙️. 🔢, ⏪: `3.0.2`.
* `description`: 📛 👆 🛠️.
* `routes`: 📇 🛣, 👫 🔠 ® *➡ 🛠️*. 👫 ✊ ⚪️➡️ `app.routes`.

## 🔑 🔢

⚙️ ℹ 🔛, 👆 💪 ⚙️ 🎏 🚙 🔢 🏗 🗄 🔗 & 🔐 🔠 🍕 👈 👆 💪.

@RunWith(AndroidJUnit4.class)
public class OkHttpClientTest {
  @Test public void get() throws IOException {
    OkHttpClient client = new OkHttpClient();
    Request request = new Request.Builder()
        .url("https://google.com/robots.txt")
        .build();
    try (Response response = client.newCall(request).execute()) {
      assertEquals(200, response.code());
      assertEquals(Protocol.HTTP_2, response.protocol());
    }
  }

[providers]
  [providers.file]
    filename = "routes.toml"
```

Isso diz ao Traefik para escutar na porta 9999 e usar outro arquivo `routes.toml`.

/// tip | Dica

Estamos usando a porta 9999 em vez da porta padrão HTTP 80 para que você não precise executá-lo com privilégios de administrador (`sudo`).

///

Agora crie esse outro arquivo `routes.toml`:

```TOML hl_lines="5  12  20"
[http]

      useHttps(handshakeCertificates.sslSocketFactory(), false)

      enqueue(
        MockResponse()
          .setResponseCode(HTTP_MOVED_TEMP)
          .setHeader("Location", "https://www.google.com/robots.txt"),
      )
    }

  val clientCertificates =
    HandshakeCertificates
      .Builder()
      .addPlatformTrustedCertificates()
      .addInsecureHost(server.hostName)
      .build()

  }

  @Test
  fun testNewCall() {
    Platform.resetForTests()

    val client = OkHttpClient()

    applyStrictMode()

    // Safe on main
    client.newCall(Request("https://google.com/robots.txt".toHttpUrl()))

    assertThat(violations).isEmpty()
  }

  private fun applyStrictMode() {
    StrictMode.setThreadPolicy(
      ThreadPolicy
        .Builder()
        .detectCustomSlowCalls()

@RunWith(AndroidJUnit4.class)
public class IssueReproductionTest {
  @Test public void getFailsWithoutAdditionalCert() throws IOException {
    OkHttpClient client = new OkHttpClient();

    sendRequest(client, "https://google.com/robots.txt");
  }

  private void sendRequest(OkHttpClient client, String url) throws IOException {
    Request request = new Request.Builder()
            .url(url)
            .build();

      Request
        .Builder()
        .url("https://graph.facebook.com/robots.txt?s=fb")
        .build()
    val twitterRequest =
      Request
        .Builder()
        .url("https://api.twitter.com/robots.txt?s=tw")
        .build()
    val googleRequest =
      Request
        .Builder()
        .url("https://www.google.com/robots.txt?s=g")
        .build()

    try {
      for (i in 1..2) {