* if the primary input succeeds, it is never invoked. If, during the invocation of {@code
   * fallback}, an exception is thrown, this exception is used as the result of the output {@code
   * Future}.
   *
   * <p>Usage example:
   *
   * <pre>{@code
   * ListenableFuture<Integer> fetchCounterFuture = ...;
   *
   * // Falling back to a zero counter in case an exception happens when
   * // processing the RPC to fetch counters.

     * <br/>
     * Note: the <code>&gt;</code> means project level, while <code>&gt;&gt;</code> means global (whole session level,
     * so even plugins will get relocated artifacts) relocation.
     * <br/>
     * For example,
     * <pre>maven.relocations.entries = org.foo:*:*>, \\<br/>    org.here:*:*>org.there:*:*, \\<br/>    javax.inject:javax.inject:1>>jakarta.inject:jakarta.inject:1.0.5</pre>

  }

  /**
   * Returns a stream in which each element is the result of passing the corresponding element of
   * each of {@code streamA} and {@code streamB} to {@code function}.
   *
   * <p>For example:
   *
   * <pre>{@code
   * Streams.zip(
   *   Stream.of("foo1", "foo2", "foo3"),
   *   Stream.of("bar1", "bar2"),
   *   (arg1, arg2) -> arg1 + ":" + arg2)
   * }</pre>
   *

  }

  private fun logWithTime(message: String) {
    val startNs = startNs
    val timeMs =
      if (startNs == null) {
        // Event occurred before start, for an example an early cancel.
        0L
      } else {
        TimeUnit.NANOSECONDS.toMillis(System.nanoTime() - startNs)
      }

    logger.invoke("[$timeMs ms] $message")
  }

{* ../../docs_src/advanced_middleware/tutorial002.py hl[2,6:8] *}

Os seguintes argumentos são suportados:

* `allowed_hosts` - Uma lista de nomes de domínio que são permitidos como nomes de host. Domínios com coringa, como `*.example.com`, são suportados para corresponder a subdomínios. Para permitir qualquer nome de host, use `allowed_hosts=["*"]` ou omita o middleware.

Se uma requisição recebida não for validada corretamente, uma resposta `400` será enviada.

	runtime.ReadMemStats(&memstats)

	gcStats := debug.GCStats{
		// If stats.PauseQuantiles is non-empty, ReadGCStats fills
		// it with quantiles summarizing the distribution of pause time.
		// For example, if len(stats.PauseQuantiles) is 5, it will be
		// filled with the minimum, 25%, 50%, 75%, and maximum pause times.
		PauseQuantiles: make([]time.Duration, 5),
	}
	debug.ReadGCStats(&gcStats)

It might also help avoid confusion for new developers that see an unused parameter in your code and could think it's unnecessary.

///

/// info

In this example we use invented custom headers `X-Key` and `X-Token`.

### 4. Test with MinIO STS API

Once etcd is configured, **any STS configuration** will work including Client Grants, Web Identity or AD/LDAP.

///

```Python hl_lines="10"
{!> ../../docs_src/header_param_models/tutorial002.py!}
```

////

If a client tries to send some **extra headers**, they will receive an **error** response.

For example, if the client tries to send a `tool` header with a value of `plumbus`, they will receive an **error** response telling them that the header parameter `tool` is not allowed:

```json
{
    "detail": [
        {

        "profiler",
        defaultProfiler,
        display = ParameterDisplay.PROMPT,
        allowEmpty = false,
        description = "Command line option for the performance test task to enable profiling. For example `async-profiler`, `async-profiler-heap`, `async-profiler-all` or `jfr`. Use `none` for benchmarking only."
    )
}

object AdHocPerformanceScenarioLinux : AdHocPerformanceScenario(Os.LINUX)