#pragma once

#include <ostream>

#include "envoy/common/optref.h"

#include "envoy/common/pure.h"

#include "envoy/stream_info/stream_info.h"

namespace Envoy {

/*

 * An interface for tracking the scope of work. Implementors of this interface

 * can be registered to the dispatcher when they're active on the stack. If a

 * fatal error occurs while they were active, the dumpState() method will be

 * called to output the active state.

 *

 * Currently this is only used for the L4 network connection and L7 stream.

 */

class ScopeTrackedObject {

public:

  /**

   * Return the tracked stream info that related to the scope tracked object (L4

   * network connection or L7 stream).

   * @return optional reference to stream info of stream (L4 connection or L7 stream).

   */

  /**

   * Dump debug state of the object in question to the provided ostream.

   *

   * This is called on Envoy fatal errors, so should do minimal memory allocation.

   *

   * @param os the ostream to output to.

   * @param indent_level how far to indent, for pretty-printed classes and subclasses.

   */

  virtual void dumpState(std::ostream& os, int indent_level = 0) const PURE;

};

} // namespace Envoy