import okhttp3.tls.HandshakeCertificates
import okhttp3.tls.internal.TlsUtil.localhost

/**
 * OkHttp is usually tested with functional tests: these use public APIs to confirm behavior against
 * MockWebServer. In cases where logic is particularly tricky, we use unit tests. This class makes
 * it easy to get sample values to use in such tests.
 *
 * This class is pretty fast and loose with default values: it attempts to provide values that are

        }
      }
    } finally {
      cancelInFlightConnects()
    }

    throw firstException!!
  }

  /**
   * Returns non-null if we don't need to wait for the launched result. In such cases, this result
   * must be processed before whatever is waiting in the queue because we may have already acquired
   * its connection.
   */
  private fun launchTcpConnect(): ConnectResult? {
    val plan =

/// tip

Here we use <a href="https://docs.python.org/3/library/time.html#time.perf_counter" class="external-link" target="_blank">`time.perf_counter()`</a> instead of `time.time()` because it can be more precise for these use cases. 🤓

///

## Multiple middleware execution order { #multiple-middleware-execution-order }

            // Then
            assertEquals(443, httpsPort);
            assertEquals(80, httpPort);
            assertNotEquals(httpsPort, httpPort);
        }
    }

    @Nested
    @DisplayName("Edge Cases")
    class EdgeCaseTests {

        @Test
        @DisplayName("Should handle reflection access to protected method")
        void testProtectedMethodAccess() throws Exception {
            // Given

/// danger | Опасность

Это «продвинутая» возможность.

Если вы только начинаете работать с **FastAPI**, возможно, стоит пропустить этот раздел.

///

## Сценарии использования { #use-cases }

Некоторые сценарии:

* Преобразование тел запросов, не в формате JSON, в JSON (например, <a href="https://msgpack.org/index.html" class="external-link" target="_blank">`msgpack`</a>).

### Tags with Enums { #tags-with-enums }

If you have a big application, you might end up accumulating **several tags**, and you would want to make sure you always use the **same tag** for related *path operations*.

In these cases, it could make sense to store the tags in an `Enum`.

**FastAPI** supports that the same way as with plain strings:

{* ../../docs_src/path_operation_configuration/tutorial002b_py39.py hl[1,8:10,13,18] *}

        assertEscaping(xmlEscaper, "\uFFFD", ch);
      }
    }

    // Test _all_ allowed characters (including surrogate values).
    for (char ch = 0x20; ch <= 0xFFFD; ch++) {
      // There are a small number of cases to consider, so just do it manually.
      if (ch == '&') {
        assertEscaping(xmlEscaper, "&amp;", ch);
      } else if (ch == '<') {
        assertEscaping(xmlEscaper, "&lt;", ch);
      } else if (ch == '>') {

---

**Note**: You can mix `def` and `async def` in your *path operation functions* as much as you need and define each one using the best option for you. FastAPI will do the right thing with them.

Anyway, in any of the cases above, FastAPI will still work asynchronously and be extremely fast.

But by following the steps above, it will be able to do some performance optimizations.

## Technical Details { #technical-details }

    * So, by using FastAPI you are saving development time, bugs, lines of code, and you would probably get the same performance (or better) you would...

///

## Forbid Extra Cookies { #forbid-extra-cookies }

In some special use cases (probably not very common), you might want to **restrict** the cookies that you want to receive.