router.include_router(sub_router)

    app = FastAPI(lifespan=lifespan)
    app.include_router(router)

    @app.get("/")
    def main(request: Request) -> dict[str, str]:
        assert request.state.app
        assert request.state.router
        assert request.state.sub_router
        return {"message": "Hello World"}

    assert state.app_startup is False
    assert state.router_startup is False

		t.Helper()
		if err != nil {
			t.Fatal(err)
		}
	}
	wrapServer := func(handler http.Handler) http.Handler {
		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
			t.Logf("Got a %s request for: %v", r.Method, r.URL)
			handler.ServeHTTP(w, r)
		})
	}
	connReady := make(chan struct{})
	// We fake a local and remote server.
	localHost := hosts[0]
	remoteHost := hosts[1]

    if (algorithms.isNotEmpty() && chain.request().header("Accept-Encoding") == null) {
      val request =
        chain
          .request()
          .newBuilder()
          .header("Accept-Encoding", acceptEncoding)
          .build()

      val response = chain.proceed(request)

      decompress(response)
    } else {
      chain.proceed(chain.request())
    }

  /**

    val call1 =
      client.newCall(
        Request
          .Builder()
          .url(server.url("/"))
          .build(),
      )
    call1.execute().use { response -> response.body.string() }

    listener.shouldClose = true
    // Large headers are a likely reason the servers would cut off the connection before it completes sending
    // request headers.
    // 431 "Request Header Fields Too Large"
    val largeHeaders =

```

We make a couple calls:

```java
Request request = new Request.Builder()
    .url("https://publicobject.com/helloworld.txt")
    .build();

System.out.println("REQUEST 1 (new connection)");
try (Response response = client.newCall(request).execute()) {
  // Consume and discard the response body.
  response.body().source().readByteString();
}

System.out.println("REQUEST 2 (pooled connection)");

        field.set(reader, eventDispatcher);

        ArtifactDescriptorRequest request = new ArtifactDescriptorRequest();

        request.addRepository(newTestRepository());

        request.setArtifact(new DefaultArtifact("org.apache.maven.its", "dep-mng5459", "jar", "0.4.0-SNAPSHOT"));

        // execute
        reader.readArtifactDescriptor(session, request);

        // verify
        verify(eventDispatcher).dispatch(event.capture());

  fun run() {
    fileSystem.write(path) {
      writeUtf8("{}")
    }

    val request =
      Request
        .Builder()
        .url("https://httpbin.org/anything")
        .put(path.asRequestBody(fileSystem, MEDIA_TYPE_JSON))
        .build()

    client.newCall(request).execute().use { response ->
      if (!response.isSuccessful) throw IOException("Unexpected code $response")

    try {
      while (true) {
        Request request = requestQueue.take();
        Object result;
        try {
          result = invokeMethod(request.methodName, request.arguments);
        } catch (ThreadDeath death) {
          return;
        } catch (InvocationTargetException exception) {
          responseQueue.put(new Response(request.methodName, null, exception.getTargetException()));
          continue;

Estos manejadores se encargan de devolver los responses JSON predeterminadas cuando lanzas un `HTTPException` y cuando el request tiene datos inválidos.

Puedes sobrescribir estos manejadores de excepciones con los tuyos propios.

### Sobrescribir excepciones de validación de request { #override-request-validation-exceptions }

Cuando un request contiene datos inválidos, **FastAPI** lanza internamente un `RequestValidationError`.

///

/// note | 技術詳細

`from starlette.requests import Request` を使用することもできます。

**FastAPI**は、開発者の便利のためにこれを提供していますが、Starletteから直接きています。

///

### `response` の前後

*path operation* が `request` を受け取る前に、 `request` とともに実行されるコードを追加できます。

また `response` が生成された後、それを返す前にも追加できます。

例えば、リクエストの処理とレスポンスの生成にかかった秒数を含むカスタムヘッダー `X-Process-Time` を追加できます: