driver/host_info.h

// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License, version 2.0
// (GPLv2), as published by the Free Software Foundation, with the
// following additional permissions:
//
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#ifndef __HOSTINFO_H__
#define __HOSTINFO_H__

#include <memory>
#include <string>
#include <sstream>

enum HOST_STATE { UP, DOWN };

// TODO Think about char types. Using strings for now, but should SQLCHAR *, or CHAR * be employed?
// Most of the strings are for internal failover things
class HOST_INFO {
public:
    HOST_INFO();
    //TODO - probably choose one of the following constructors, or more precisely choose which data type they should take
    HOST_INFO(std::string host, int port);
    HOST_INFO(const char* host, int port);
    HOST_INFO(std::string host, int port, HOST_STATE state, bool is_writer);
    HOST_INFO(const char* host, int port, HOST_STATE state, bool is_writer);
    ~HOST_INFO();

    int get_port();
    std::string get_host();
    std::string get_host_id();
    std::string get_host_port_pair();
    bool equal_host_port_pair(HOST_INFO& hi);
    HOST_STATE get_host_state();
    void set_host_state(HOST_STATE state);
    bool is_host_up();
    bool is_host_down();
    bool is_host_writer();
    void mark_as_writer(bool writer);
    static bool is_host_same(std::shared_ptr<HOST_INFO> h1, std::shared_ptr<HOST_INFO> h2);
    static constexpr int NO_PORT = -1;

    // used to be properties - TODO - remove the ones that are not necessary
    std::string session_id;
    std::string last_updated;
    std::string replica_lag;
    std::string instance_name;

private:
    const std::string HOST_PORT_SEPARATOR = ":";
    const std::string host;
    const std::string host_id;
    const int port = NO_PORT;

    HOST_STATE host_state;
    bool is_writer;
};

inline std::ostream& operator<<(std::ostream& str, HOST_INFO v) {
    char buf[1024];
    sprintf(buf, "HostSpec[host=%s, port=%d, %s, %s]", v.get_host().c_str(), v.get_port(),
            v.is_host_writer() ? "WRITER" : "READER", v.last_updated.c_str());
    return str << std::string(buf);
}

#endif /* __HOSTINFO_H__ */