taskqueue/taskqueue.go
func ModifyLease(c context.Context, task *Task, queueName string, leaseTime int) error {
	if queueName == "" {
		queueName = "default"
	}
	req := &pb.TaskQueueModifyTaskLeaseRequest{
		QueueName:    []byte(queueName),
		TaskName:     []byte(task.Name),
		EtaUsec:      proto.Int64(task.ETA.UnixNano() / 1e3), // Used to verify ownership.
		LeaseSeconds: proto.Float64(float64(leaseTime)),
	}
	res := &pb.TaskQueueModifyTaskLeaseResponse{}
	if err := internal.Call(c, "taskqueue", "ModifyTaskLease", req, res); err != nil {
		return err
	}
	task.ETA = time.Unix(0, *res.UpdatedEtaUsec*1e3)
	return nil
}
func ModifyLease(c context.Context, task *Task, queueName string, leaseTime int) error {
	if queueName == "" {
		queueName = "default"
	}
	req := &pb.TaskQueueModifyTaskLeaseRequest{
		QueueName:    []byte(queueName),
		TaskName:     []byte(task.Name),
		EtaUsec:      proto.Int64(task.ETA.UnixNano() / 1e3), // Used to verify ownership.
		LeaseSeconds: proto.Float64(float64(leaseTime)),
	}
	res := &pb.TaskQueueModifyTaskLeaseResponse{}
	if err := internal.Call(c, "taskqueue", "ModifyTaskLease", req, res); err != nil {
		return err
	}
	task.ETA = time.Unix(0, *res.UpdatedEtaUsec*1e3)
	return nil
}
// ModifyLease modifies the lease of a task.
// Used to request more processing time, or to abandon processing.
// leaseTime is in seconds and must not be negative.