* connections should expect repetition of stream IDs.
 *
 * Return true to request cancellation of a pushed stream.  Note that this does not guarantee
 * future frames won't arrive on the stream ID.
 */
interface PushObserver {
  /**
   * Describes the request that the server intends to push a response for.
   *
   * @param streamId server-initiated stream ID: an even number.

	}
	for _, v := range headers {
		req := &http.Request{
			Header: http.Header{
				v.key: []string{v.val},
			},
		}
		res := GetSourceScheme(req)
		if res != v.expected {
			t.Errorf("wrong header for %s: got %s want %s", v.key, res,
				v.expected)
		}
	}
}

// TestGetSourceIP - check the source ip of a request is parsed correctly.
func TestGetSourceIP(t *testing.T) {

import com.google.common.annotations.GwtIncompatible;
import com.google.common.annotations.J2ktIncompatible;
import java.io.IOException;
import java.io.Reader;
import java.nio.CharBuffer;
import org.jspecify.annotations.Nullable;

/**
 * A {@link Reader} that reads the characters in a {@link CharSequence}. Like {@code StringReader},
 * but works with any {@link CharSequence}.
 *
 * @author Colin Decker
 */

	}
	testCases := []struct {
		req         *http.Request
		expectedErr error
	}{
		// Set valid authorization header.
		{
			req: &http.Request{
				Header: http.Header{
					"Authorization": []string{token},
				},
			},
			expectedErr: nil,
		},
		// No authorization header.
		{
			req: &http.Request{
				Header: http.Header{},
			},
			expectedErr: errNoAuthToken,
		},

        request.requestType(ModelBuilderRequest.RequestType.BUILD_CONSUMER);
        request.session(iSession);
        request.source(src);
        request.locationTracking(false);
        request.systemProperties(session.getSystemProperties());
        request.userProperties(session.getUserProperties());

        Doc(
            """
            By default, after a dependency is called the first time in a request, if
            the dependency is declared again for the rest of the request (for example
            if the dependency is needed by several dependencies), the value will be
            re-used for the rest of the request.

            Set `use_cache` to `False` to disable this behavior and ensure the

        }
        SearchRequest request = new SearchRequest();
        request.source(new SearchSourceBuilder().size(0).aggregation(AggregationBuilders.terms("test")));
        request.setBatchedReduceSize(bufferSize);
        ExecutorService executor = Executors.newFixedThreadPool(1);
        QueryPhaseResultConsumer consumer = new QueryPhaseResultConsumer(
            request,
            executor,

		d.replaceHashed(dataUsageHash(key), &eHash, existing)
	}
}

type objectIO interface {
	GetObjectNInfo(ctx context.Context, bucket, object string, rs *HTTPRangeSpec, h http.Header, opts ObjectOptions) (reader *GetObjectReader, err error)
	PutObject(ctx context.Context, bucket, object string, data *PutObjReader, opts ObjectOptions) (objInfo ObjectInfo, err error)
}

        // Send FSCTL_QUERY_NETWORK_INTERFACE_INFO per MS-SMB2 3.2.4.23
        Smb2IoctlRequest request =
                new Smb2IoctlRequest(context.getConfig(), Smb2IoctlRequest.FSCTL_QUERY_NETWORK_INTERFACE_INFO, new byte[16] // Reserved/Unused file ID
                );
        request.setMaxOutputResponse(65536);
        request.setFlags(Smb2IoctlRequest.SMB2_O_IOCTL_IS_FSCTL);

若有背景工作（在[背景工作](background-tasks.md)一節會介紹，你稍後會看到），它們會在所有中介軟體之後執行。

///

## 建立中介軟體 { #create-a-middleware }

要建立中介軟體，將裝飾器 `@app.middleware("http")` 加在函式上方。

中介軟體函式會接收：

- `request`。
- 一個函式 `call_next`，會以 `request` 作為參數。
    - 這個函式會把 `request` 傳給對應的*路徑操作*。
    - 然後回傳對應*路徑操作*所產生的 `response`。
- 然後你可以在回傳之前進一步修改 `response`。

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

/// tip