link_client.h

#pragma once
 
//
// Copyright (c) 2019-2023 Ivan Baidakou (basiliscos) (the dot dmol at gmail dot com)
//
// Distributed under the MIT Software License
//
 
#include "plugin_base.h"
#include <string>
#include <unordered_map>
#include <functional>
#include <forward_list>
 
#if defined(_MSC_VER)
#pragma warning(push)
#pragma warning(disable : 4251)
#endif
 
namespace rotor::plugin {

struct ROTOR_API link_client_plugin_t : public plugin_base_t {
    using link_callback_t = std::function<void(const extended_error_ptr_t &)>;

    using unlink_reaction_t = std::function<bool(message::unlink_request_t &message)>;
 
    using plugin_base_t::plugin_base_t;

    static const std::type_index class_identity;
 
    const std::type_index &identity() const noexcept override;
 
    void activate(actor_base_t *actor) noexcept override;

    virtual void link(const address_ptr_t &address, bool operational_only = true,
                      const link_callback_t &callback = {}) noexcept;

    template <typename F> void on_unlink(F &&callback) noexcept { unlink_reaction = std::forward<F>(callback); }

    virtual void on_link_response(message::link_response_t &message) noexcept;

    virtual void on_unlink_request(message::unlink_request_t &message) noexcept;
 
    bool handle_shutdown(message::shutdown_request_t *message) noexcept override;
    bool handle_init(message::init_request_t *message) noexcept override;

    void forget_link(message::unlink_request_t &message) noexcept;
 
  private:
    enum class link_state_t { LINKING, OPERATIONAL, UNLINKING };
    struct server_record_t {
        link_callback_t callback;
        link_state_t state;
        request_id_t request_id;
    };
    using servers_map_t = std::unordered_map<address_ptr_t, server_record_t>;
    using unlink_req_t = intrusive_ptr_t<message::unlink_request_t>;
    using unlink_queue_t = std::list<unlink_req_t>;
 
    void try_forget_links(bool attempt_shutdown) noexcept;
    servers_map_t servers_map;
    unlink_reaction_t unlink_reaction;
    unlink_queue_t unlink_queue;
    bool configured = false;
};
 
} // namespace rotor::plugin
 
#if defined(_MSC_VER)
#pragma warning(pop)
#endif