///

## Criar um middleware

Para criar um middleware, use o decorador `@app.middleware("http")` logo acima de uma função.

A função middleware recebe:

* A `request`.
* Uma função `call_next` que receberá o `request` como um parâmetro.
    * Esta função passará a `request` para a *operação de rota* correspondente.
    * Então ela retorna a `response` gerada pela *operação de rota* correspondente.

    public void setDelegate(ArtifactMetadataSource delegate) {
        this.delegate = delegate;
    }

    @Override
    public ResolutionGroup retrieve(MetadataResolutionRequest request) throws ArtifactMetadataRetrievalException {
        return delegate.retrieve(request);
    }

    @Override
    public ResolutionGroup retrieve(
            Artifact artifact, ArtifactRepository localRepository, List<ArtifactRepository> remoteRepositories)

import java.net.Proxy.Type.SOCKS
import okhttp3.HttpUrl.Companion.toHttpUrl
import okhttp3.OkHttpClient
import okhttp3.Request
import okhttp3.containers.BasicMockServerTest.Companion.MOCKSERVER_IMAGE
import org.junit.jupiter.api.Test
import org.mockserver.client.MockServerClient
import org.mockserver.model.HttpRequest.request
import org.mockserver.model.HttpResponse.response
import org.testcontainers.containers.GenericContainer

    OkHttpDebugLogging.enable("org.bouncycastle.jsse")
    platform.assumeBouncyCastle()
  }

  @Test
  fun testMozilla() {
    assumeNetwork()

    val request = Request.Builder().url("https://mozilla.org/robots.txt").build()

    client.newCall(request).execute().use {
      assertThat(it.protocol).isEqualTo(Protocol.HTTP_2)
      assertThat(it.handshake!!.tlsVersion).isEqualTo(TlsVersion.TLS_1_3)
    }
  }

	}
	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,
		},

        Set<String> roleSet = new HashSet<>();
        roleQueryHelperImpl.processParameter(request, roleSet);
        return roleSet;
    }

    private Set<String> buildByHeader(final RoleQueryHelper roleQueryHelperImpl, final HttpServletRequest request) {
        Set<String> roleSet = new HashSet<>();
        roleQueryHelperImpl.processHeader(request, roleSet);
        return roleSet;
    }

		date    time.Time
		region  string
		service string
		request string
	}
}

// Return scope string.
func (c credentialHeader) getScope() string {
	return strings.Join([]string{
		c.scope.date.Format(yyyymmdd),
		c.scope.region,
		c.scope.service,
		c.scope.request,
	}, SlashSeparator)
}

func getReqAccessKeyV4(r *http.Request, region string, stype serviceType) (auth.Credentials, bool, APIErrorCode) {

type Op uint8

// HandlerID is the ID for the handler of a specific type.
type HandlerID uint8

const (
	// OpConnect is a connect request.
	OpConnect Op = iota + 1

	// OpConnectResponse is a response to a connect request.
	OpConnectResponse

	// OpPing is a ping request.
	// If a mux id is specified that mux is pinged.
	// Clients send ping requests.
	OpPing

	// OpPong is a OpPing response returned by the server.

    route: Route?,
    response: Response,
  ): Request? {
    if (route == null) throw NullPointerException("route == null")
    responses += response
    routes += route
    if (!schemeMatches(response) || credential == null) return null
    val header =
      when (response.code) {
        407 -> "Proxy-Authorization"
        else -> "Authorization"
      }
    return response.request.newBuilder()
      .addHeader(header, credential)

import org.robolectric.annotation.Implements
import org.robolectric.shadow.api.Shadow

@Implements(DnsResolver::class)
class ShadowDnsResolver {
  var responder: (Request) -> Unit = {
    it.callback.onAnswer(listOf(), 0)
  }

  data class Request(
    val network: Network?,
    val domain: String,
    val nsType: Int,
    val flags: Int,
    val callback: DnsResolver.Callback<List<InetAddress>>,
  )