## Gerenciadores de contexto

### O que são gerenciadores de contexto

"Gerenciadores de Contexto" são qualquer um dos objetos Python que podem ser utilizados com a declaração `with`.

}

// extractMetadataFromReq extracts metadata from HTTP header and HTTP queryString.
func extractMetadataFromReq(ctx context.Context, r *http.Request) (metadata map[string]string, err error) {
	return extractMetadata(ctx, textproto.MIMEHeader(r.Form), textproto.MIMEHeader(r.Header))
}

func extractMetadata(ctx context.Context, mimesHeader ...textproto.MIMEHeader) (metadata map[string]string, err error) {
	metadata = make(map[string]string)

        op_outputs_ = std::vector<TensorHandlePtr>();
        Execute(context_, operation_name_, std::move(op_inputs_), attributes_,
                expected_max_outputs_, &op_outputs_, status_.get());
        execution_state_ = ExecutionState::kHasResult;
      }
    }
    finished_execute_.notify_one();
  }
}

void DeviceThread::StartExecute(TFE_Context* context,
                                const char* operation_name,

	ctx, cancel := context.WithTimeout(ctx, ds.Timeouts.Acquire)
	defer cancel()

	// Special context for NetLockers - do not use timeouts.
	// Also, pass the trace context info if found for debugging
	netLockCtx := context.Background()
	tc, ok := ctx.Value(mcontext.ContextTraceKey).(*mcontext.TraceCtxt)
	if ok {
		netLockCtx = context.WithValue(netLockCtx, mcontext.ContextTraceKey, tc)
	}

	_, _, s3Err = checkRequestAuthTypeCredential(ctx, r, action)
	return s3Err
}

func authenticateRequest(ctx context.Context, r *http.Request, action policy.Action) (s3Err APIErrorCode) {
	if logger.GetReqInfo(ctx) == nil {
		bugLogIf(ctx, errors.New("unexpected context.Context does not have a logger.ReqInfo"), logger.ErrorKind)
		return ErrAccessDenied
	}

	var cred auth.Credentials
	var owner bool
	switch getRequestAuthType(r) {

		}
		content.Key = s3EncodeName(object.Name, encodingType)
		content.LastModified = amztime.ISO8601Format(object.ModTime.UTC())
		if object.ETag != "" {
			content.ETag = "\"" + object.ETag + "\""
		}
		content.Size = object.Size
		if object.StorageClass != "" {
			content.StorageClass = filterStorageClass(ctx, object.StorageClass)
		} else {
			content.StorageClass = globalMinioDefaultStorageClass
		}
		content.Owner = owner

  name: {cluster}
contexts:
- context:
    cluster: {cluster}
    user: {cluster}
  name: {cluster}
current-context: {cluster}
kind: Config
preferences: {}
users:
- name: {cluster}
  user:
    token: token
`, "{cluster}", fakeClusterName)

	cases := []struct {
		name               string
		clusterName        string
		context            string
		server             string

		tc, ok := r.Context().Value(mcontext.ContextTraceKey).(*mcontext.TraceCtxt)
		if ok {
			tc.FuncName = "handler.MetricsLegacy"
			tc.ResponseRecorder.LogErrBody = true
		}

		mfs, err := gatherers.Gather()
		if err != nil {
			if len(mfs) == 0 {
				writeErrorResponseJSON(r.Context(), w, toAdminAPIErr(r.Context(), err), r.URL)
				return
			}
		}

func remoteSecretNameFromClusterName(clusterName string) string {
	return remoteSecretPrefix + clusterName
}

// NewCreateRemoteSecretCommand creates a new command for joining two contexts
// together in a multi-cluster mesh.
func NewCreateRemoteSecretCommand(ctx cli.Context) *cobra.Command {
	opts := RemoteSecretOptions{
		AuthType:         RemoteSecretAuthTypeBearerToken,
		AuthPluginConfig: make(map[string]string),

			}
		}
		sr, err := globalDNSConfig.Get(bucket)
		if err != nil {
			defer logger.AuditLog(r.Context(), w, r, mustGetClaimsFromToken(r))
			if err == dns.ErrNoEntriesFound {
				writeErrorResponse(r.Context(), w, errorCodes.ToAPIErr(ErrNoSuchBucket), r.URL)
			} else {
				writeErrorResponse(r.Context(), w, toAPIError(r.Context(), err), r.URL)
			}
			return
		}