#### A "professional" attack { #a-professional-attack }

Of course, the attackers would not try all this by hand, they would write a program to do it, possibly with thousands or millions of tests per second. And they would get just one extra correct letter at a time.

But doing that, in some minutes or hours the attackers would have guessed the correct username and password, with the "help" of our application, just using the time taken to answer.

	m.mu.RUnlock()
	if ok {
		return b.updateCacheEntry(update)
	}

	// We should have either a trashed bucket or this
	return metacache{}, errVolumeNotFound
}

// getBucket will get a bucket metacache or load it from disk if needed.
func (m *metacacheManager) getBucket(ctx context.Context, bucket string) *bucketMetacache {
	m.init.Do(m.initManager)

		reqRecorder := &xhttp.RequestRecorder{Reader: r.Body}
		r.Body = reqRecorder

		// Create tracing data structure and associate it to the request context
		tc := mcontext.TraceCtxt{
			AmzReqID:         w.Header().Get(xhttp.AmzRequestID),
			RequestRecorder:  reqRecorder,
			ResponseRecorder: respRecorder,
		}

		r = r.WithContext(context.WithValue(r.Context(), mcontext.ContextTraceKey, &tc))

		reqStartTime := time.Now().UTC()

// AuthZPlugin - implements opa policy agent calls.
type AuthZPlugin struct {
	args   Args
	client *http.Client
}

// Enabled returns if AuthZPlugin is enabled.
func Enabled(kvs config.KVS) bool {
	return kvs.Get(URL) != ""
}

// LookupConfig lookup AuthZPlugin from config, override with any ENVs.
func LookupConfig(s config.Config, httpSettings xhttp.ConnSettings, closeRespFn func(io.ReadCloser)) (Args, error) {
	args := Args{}

  }

  private String[] javaNames(List<CipherSuite> cipherSuites) {
    String[] result = new String[cipherSuites.size()];
    for (int i = 0; i < result.length; i++) {
      result[i] = cipherSuites.get(i).javaName();
    }
    return result;
  }

  /**
   * An SSL socket factory that forwards all calls to a delegate. Override {@link #configureSocket}
   * to customize a created socket before it is returned.

        ) {
        }
      },
    )

    // This should fail the Call, but not cause an unhandled Exception bubbling up
    client.dispatcher.executorService.shutdownNow()

    val exception = callFailure.get(5, TimeUnit.SECONDS)
    assertThat(exception.message)
      .isNotNull()
      .startsWith("canceled due to")
    assertThat(exception).isInstanceOf<IOException>()
    assertThat(exception.cause)
      .isNotNull()

        if (edges == null || edges.isEmpty()) {
            return null;
        }

        if (edges.size() == 1) {
            MetadataGraphEdge e = edges.get(0);
            if (scope.encloses(e.getScope())) {
                return e;
            }

            return null;
        }

        MetadataGraphEdge res = null;

Luego podemos crear un `AsyncClient` con la app y enviar requests asíncronos a ella, usando `await`.

{* ../../docs_src/async_tests/app_a_py39/test_main.py hl[9:12] *}

Esto es equivalente a:

```Python
response = client.get('/')
```

...que usábamos para hacer nuestros requests con el `TestClient`.

/// tip | Consejo

Nota que estamos usando async/await con el nuevo `AsyncClient`: el request es asíncrono.

///

    bits += signifRounded;
    /*
     * If signifRounded == 2^53, we'd need to set all of the significand bits to zero and add 1 to
     * the exponent. This is exactly the behavior we get from just adding signifRounded to bits
     * directly. If the exponent is MAX_DOUBLE_EXPONENT, we round up (correctly) to
     * Double.POSITIVE_INFINITY.
     */
    bits |= x.signum() & SIGN_MASK;

      while (same != 0xffffffff || diff != 0xffffffff) {
        int key1 = rand.nextInt();
        // flip input bit for key2
        int key2 = key1 ^ (1 << i);
        // get hashes
        int hash1 = function.hashInt(key1).asInt();
        int hash2 = function.hashInt(key2).asInt();
        // test whether the hash values have same output bits
        same |= ~(hash1 ^ hash2);