Method AsyncDataSource

src/core/DataSource.h:123–126

class AsyncDataSource : public DataSource<T> {
 public:
  explicit AsyncDataSource(std::unique_ptr<DataSource<T>> source) {
    task = std::make_shared<DataTask<T>>(std::move(source));
    Task::Run(task);
  }

  ~AsyncDataSource() override {
    task->cancel();