Puedes añadir código que se ejecute con la `request`, antes de que cualquier *path operation* la reciba.

Y también después de que se genere la `response`, antes de devolverla.

Por ejemplo, podrías añadir un custom header `X-Process-Time` que contenga el tiempo en segundos que tomó procesar la request y generar una response:

{* ../../docs_src/middleware/tutorial001_py39.py hl[10,12:13] *}

/// tip | Consejo

	// ErrIncompatibleEncryptionMethod indicates that both SSE-C headers and SSE-S3 headers were specified, and are incompatible
	// The client needs to remove the SSE-S3 header or the SSE-C headers
	ErrIncompatibleEncryptionMethod = Errorf("Server side encryption specified with both SSE-C and SSE-S3 headers")

        allHeaders.put(null, Collections.singletonList(statusLine)); // Status line
        when(conn.getHeaderFields()).thenReturn(allHeaders);

        // Mock individual header access by both string key and index
        if (headers != null) {
            // Mock by header name
            for (Map.Entry<String, List<String>> entry : headers.entrySet()) {
                when(conn.getHeaderField(entry.getKey())).thenReturn(entry.getValue().get(0));

// csvSplitSize is the size of each block.
// Blocks will read this much and find the first following newline.
// 128KB appears to be a very reasonable default.
const csvSplitSize = 128 << 10

// startReaders will read the header if needed and spin up a parser
// and a number of workers based on GOMAXPROCS.
// If an error is returned no goroutines have been started and r.err will have been set.

          } catch (e: Exception) {
            false
          }
        }.build()

    val request =
      Request
        .Builder()
        .url("https://sni.cloudflaressl.com/cdn-cgi/trace")
        .header("Host", "cloudflare-dns.com")
        .build()
    client.newCall(request).execute().use { response ->
      assertThat(response.code).isEqualTo(200)
      assertThat(response.protocol).isEqualTo(Protocol.HTTP_2)

	// Version numbers.
	zipVersion20 = 20 // 2.0
	zipVersion45 = 45 // 4.5 (reads and writes zip64 archives)

	// Limits for non zip64 files.
	uint16max = (1 << 16) - 1
	uint32max = (1 << 32) - 1

	// Extra header IDs.
	//
	// IDs 0..31 are reserved for official use by PKWARE.
	// IDs above that range are defined by third-party vendors.
	// Since ZIP lacked high precision timestamps (nor an official specification

        }

        return this.size;
    }

    private static String readString(final byte[] buffer, int bufferIndex, final int len) {
        // this is not absolutely correct, but we assume that the header is aligned
        if (bufferIndex % 2 != 0) {
            bufferIndex++;
        }
        return Strings.fromUNIBytes(buffer, bufferIndex, Strings.findUNITermination(buffer, bufferIndex, len));
    }

	stsErr := stsErrCodes.ToSTSErr(errCode)

	// Generate error response.
	stsErrorResponse := STSErrorResponse{}
	stsErrorResponse.Error.Code = stsErr.Code
	stsErrorResponse.RequestID = w.Header().Get(xhttp.AmzRequestID)
	stsErrorResponse.Error.Message = stsErr.Description
	if err != nil {
		stsErrorResponse.Error.Message = err.Error()
	}
	switch errCode {
	case ErrSTSInternalError, ErrSTSUpstreamError:

        <!-- to enable SuppressWarningsFilter -->
        <module name="SuppressWarningsHolder"/>
    </module>
    <module name="RegexpHeader">
        <property name="headerFile" value="${config_loc}/required-header.txt"/>
    </module>
    <module name="FileTabCharacter"/>
    <module name="RegexpSingleline">
        <property name="format" value="File \| Settings \| File Templates"/>
    </module>

// parse size from content-range header
func parseSizeFromContentRange(h http.Header) (sz int64, err error) {
	cr := h.Get(xhttp.ContentRange)
	if cr == "" {
		return sz, fmt.Errorf("Content-Range not set")
	}
	parts := contentRangeRegexp.FindStringSubmatch(cr)
	if len(parts) != 4 {
		return sz, fmt.Errorf("invalid Content-Range header %s", cr)
	}
	if parts[3] == "*" {
		return -1, nil
	}