so_5/parent_coop/main.cpp

/*
 * Parent-child cooperations sample.
 *
 * The sample shows:
 * - how to create a child-cooperation (cooperation, which has some parent
 *   cooperation).
 * - auto-deregistration of the child-cooperation if the parent cooperation is
 *   deregistering.
 *
 * Parent agent creates a child agent, which do some task. 
 * If parent cooperation is deregistering, the child cooperation will be
 * deregistered automatically.
 */

#include <iostream>
#include <sstream>

// Main SObjectizer header file.
#include <so_5/all.hpp>

// Result of task which will be send to a parent agent.
struct task_result
{
  unsigned int m_id;
};

// Child finished to do his task.
class task_completed final : public so_5::signal_t {}; 

// Child agent.
/*
  This agent will be created in his own cooperation.
  Agent does some task, sends a result to the parent agent and closes down.
*/
class a_child_t final : public so_5::agent_t
{
  public:
    a_child_t(
      context_t ctx,
      so_5::mbox_t result_mbox,
      unsigned int task_id ) 
      : so_5::agent_t( ctx )
      , m_result_mbox( std::move(result_mbox) )
      , m_task_id( task_id )
    {}

    ~a_child_t() override
    {
      std::cout << "Child: agent of the task " << m_task_id
          << " has destroyed." << std::endl;
    }

    // Definition of the agent for SObjectizer.
    void so_define_agent() override
    {
      so_subscribe_self().event( &a_child_t::evt_task_completed );
    }

    // A reaction to start of work in SObjectizer.
    void so_evt_start() override
    {
      std::cout << "Child: has started to do task " << m_task_id << std::endl;

      so_5::send_delayed< task_completed >( *this, std::chrono::seconds( 1 ) ); 
    }

    void so_evt_finish() override
    {
      std::cout << "Child: has finished, task " << m_task_id << std::endl;
    }

    void evt_task_completed( mhood_t< task_completed > )
    {
      std::cout << "Child: has completed his task " << m_task_id << std::endl;

      // Send information about result to the parent agent.
      so_5::send< task_result >( m_result_mbox, m_task_id );

      // Deregister child cooperation and close 
      // down activity of this child instance.
      so_deregister_agent_coop_normally();
    }

  private:
    // Result mbox.
    const so_5::mbox_t m_result_mbox; 

    // Task ID.
    const unsigned int m_task_id;
};

// Parent agent in his parent cooperation.
class a_parent_t final : public so_5::agent_t
{
  public:
    using so_5::agent_t::agent_t;

    ~a_parent_t() override
    {
      std::cout << "Parent: agent has destroyed." << std::endl;
    }

    // Definition of the agent for SObjectizer.
    void so_define_agent() override
    {
      so_subscribe_self().event( &a_parent_t::evt_task_result );
    }

    // A reaction to start of work in SObjectizer.
    void so_evt_start() override
    {
      std::cout << "Parent: agent has started." << std::endl;

      // Our cooperation has created. We may start a child agent work.
      start_child( 0 );
    }

    void so_evt_finish() override
    {
      std::cout << "Parent: agent has finished." << std::endl;
    }

    // Task result received from child-agent.
    void evt_task_result( const task_result & evt )
    {
      std::cout << "Parent: task result " << evt.m_id << " is received." << std::endl;

      // We will start to do a next task.
      start_child( evt.m_id + 1 );
    }

  private:
    // Starts child to solve a task number ID.
    void start_child( unsigned int id )
    {
      std::cout << "Parent: starting a child to do task " << id << std::endl;

      // Creating a child cooperation.
      so_5::introduce_child_coop( *this,
        [&]( so_5::coop_t & coop ) {
          // Adding agents to the cooperation.
          coop.make_agent< a_child_t >( so_direct_mbox(), id );
        } );
    }
};

int main()
{
  try
  {
    so_5::launch( []( so_5::environment_t & env )
      {
        // Registering the parent cooperation.
        env.register_agent_as_coop( env.make_agent< a_parent_t >() );

        // Give some time to the agents.
        std::this_thread::sleep_for( std::chrono::seconds( 3 ) );
        env.stop();
      } );
  }
  catch( const std::exception & ex )
  {
    std::cerr << "Error: " << ex.what() << std::endl;
    return 1;
  }

  return 0;
}