reader.h

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#ifndef MYSQL_CSA_READER_H
#define MYSQL_CSA_READER_H
 
#include <memory>
#include "sql/changestreams/apply/jobs/job.h"
 
namespace mysql::csa {
 
/// @brief Abstract interface for reading jobs from a storage source.
///
/// This class defines methods for reading Job objects and checking the status
/// of the Change Stream Applier (CSA).
class Reader;
/// Shared reader type
using Reader_sptr = std::shared_ptr<Reader>;
 
class Reader {
 public:
  /// @brief Reads and returns a unique pointer to a Job object.
  ///
  /// This method is responsible for reading data and creating a Job.
  /// @return A unique pointer to the Job read from the storage.
  virtual Job_ptr read() = 0;
  /// @brief Checks whether the Change Stream Applier (CSA) is stopped.
  ///
  /// @return true if a stop was requested, false otherwise.
  virtual bool is_stopped() const = 0;
  /// @brief Checks whether the Change Stream Applier (CSA) has encountered an
  /// error.
  ///
  /// @return true if an error occurred, false otherwise.
  virtual bool is_error() const = 0;
  /// Destructor
  virtual ~Reader() = default;
  /// Stops the reader
  virtual void stop() = 0;
};
 
}  // namespace mysql::csa
 
#endif  // MYSQL_CSA_READER_H