ModTime: zipObjInfo.ModTime,
	}

	// Set standard object headers.
	if err = setObjectHeaders(ctx, w, objInfo, nil, opts); err != nil {
		writeErrorResponseHeadersOnly(w, toAPIError(ctx, err))
		return
	}

	// s3zip does not allow ranges.
	w.Header().Del(xhttp.AcceptRanges)

	// Set any additional requested response headers.
	setHeadGetRespHeaders(w, r.Form)

	// Successful response.

        response.headers["X-Custom"] = "modified"
        return response

    @app.get("/")
    def endpoint(response: Annotated[Response, Depends(modify_response)]):
        return {"status": "ok"}

    client = TestClient(app)
    resp = client.get("/")

    assert resp.status_code == 200
    assert resp.json() == {"status": "ok"}
    assert resp.headers.get("X-Custom") == "modified"

    processed_keys = set()

    for field in fields_to_extract:
        alias = None
        if isinstance(received_params, Headers):
            # Handle fields extracted from a Pydantic Model for a header, each field
            # doesn't have a FieldInfo of type Header with the default convert_underscores=True
            convert_underscores = getattr(

{* ../../docs_src/middleware/tutorial001_py310.py hl[8:9,11,14] *}

/// tip

Keep in mind that custom proprietary headers can be added [using the `X-` prefix](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers).

        this.sentRequestMillis = cacheResponse.sentRequestAtMillis
        this.receivedResponseMillis = cacheResponse.receivedResponseAtMillis
        val headers = cacheResponse.headers
        for (i in 0 until headers.size) {
          val fieldName = headers.name(i)
          val value = headers.value(i)
          when {
            fieldName.equals("Date", ignoreCase = true) -> {
              servedDate = value.toHttpDateOrNull()

    server.enqueue(
      MockResponse(
        headers =
          headersOf(
            "Last-Modified",
            formatDate(-1, TimeUnit.HOURS)!!,
            "Expires",
            formatDate(1, TimeUnit.HOURS)!!,
          ),
        body = "ABC.1",
      ),
    )
    server.enqueue(
      MockResponse(
        headers =
          headersOf(
            "Last-Modified",

            licenseHeaderFile = new File(root, "build-tools-internal/src/main/resources/license-headers/elastic-license-2.0-header.txt");
        } else {
            licenseHeaderFile = new File(root, "build-tools-internal/src/main/resources/license-headers/sspl+elastic-license-header.txt");
        }

        String lineSeparator = Os.isFamily(Os.FAMILY_WINDOWS) ? "\\\\r\\\\n" : "\\\\n";

### CORS 预检请求 { #cors-preflight-requests }

这是些带有 `Origin` 和 `Access-Control-Request-Method` 请求头的 `OPTIONS` 请求。

在这种情况下，中间件将拦截传入的请求并进行响应，出于提供信息的目的返回一个使用了适当的 CORS headers 的 `200` 或 `400` 响应。

### 简单请求 { #simple-requests }

任何带有 `Origin` 请求头的请求。在这种情况下，中间件将像平常一样传递请求，但是在响应中包含适当的 CORS headers。

## 更多信息 { #more-info }

## 代理轉發標頭 { #proxy-forwarded-headers }

當你使用代理處理 HTTPS 時，你的**應用伺服器**（例如透過 FastAPI CLI 啟動的 Uvicorn）其實不知道任何 HTTPS 的處理流程，它是用純 HTTP 與 **TLS 終止代理**通訊。

這個**代理**通常會在把請求轉發給**應用伺服器**之前，臨時加入一些 HTTP 標頭，讓應用伺服器知道該請求是由代理**轉發**過來的。

/// note | 技術細節

這些代理標頭包括：

* [X-Forwarded-For](https://developer.mozilla.org/en-US/docs/Web/HTTP/Reference/Headers/X-Forwarded-For)

 *    * connection held ([connectionAcquired], [connectionReleased])
 *      * request ([requestFailed])
 *        * headers ([requestHeadersStart], [requestHeadersEnd])
 *        * body ([requestBodyStart], [requestBodyEnd])
 *      * response ([responseFailed])
 *        * headers ([responseHeadersStart], [responseHeadersEnd])
 *        * body ([responseBodyStart], [responseBodyEnd])
 *