Implemented first part of http proxy ability.

[bpdyndnsd] / src / updater.cpp

/** @file
 * @brief The updater class implementation. This class implements the updater logic.
 *
 *
 *
 * @copyright Intra2net AG
 * @license GPLv2
*/

#include "updater.h"

#include "serviceholder.h"
#include "dhs.h"
#include "ods.h"

#include <boost/foreach.hpp>


// Following boost macros are needed for serialization of derived classes through a base class pointer (Service *).
BOOST_CLASS_EXPORT_GUID(ODS, "ODS")
BOOST_CLASS_EXPORT_GUID(DHS, "DHS")

namespace fs = boost::filesystem;

using namespace std;

/**
 * Default constructor which initializes the member Conf.
 */
Updater::Updater()
    : IPHelp(new IPHelper)
{
    // Initialize program wide Logger, at this point we don't know where to log and with which loglevel.
    Logger::Ptr _log(new Logger);
    Log = _log;
    _log.reset();

    // initialize Serviceholder
    Serviceholder::Ptr _serviceholder(new Serviceholder(Log));
    ServiceHolder = _serviceholder;
    _serviceholder.reset();

    // initialize Config
    Config::Ptr _config(new Config(Log,ServiceHolder));
    Conf = _config;
    _config.reset();
}


/**
 * Default destructor.
 */
Updater::~Updater()
{
}


/**
 * Parse the command line arguments and initialize corresponding options.
 * @param argc Number command line arguments.
 * @param argv[] Array with arguments.
 * @return 0 if cmd options successfully parsed, 1 if usage or version.
 */
int Updater::init_config_from_cmd(int argc, char *argv[])
{
    // Load the command line parameters
    if( Conf->parse_cmd_line( argc, argv) != 0)
        return -1;

    // If we have loaded the cmd options we need to init the log facility immediately in case debugging is enabled from cmd.
    init_log_facility();

    // successful parsed
    Log->print_cmd_parsed();
    return 0;
}


/**
 * Load the main config and the service definition files in config path.
 * @return 0 if all is fine, 
 */
int Updater::init_config_from_files()
{
    // Load the main and service config files in config path
    if ( Conf->load_config_from_files() != 0 )
        return -1;

    // Re-init log facility, perhaps new config file options for logger are set.
    // These config file options will only overwrite the cmd options if the SIGHUP (reload config) is caught.
    init_log_facility();

    // Here we are. All Service Objects should be initialized, so it is time to deserialize the old service objects and compare them.
    if ( ServiceHolder->deserialize_services() != 0 )
        return -1;

    // successful loaded
    Log->print_conf_files_parsed();
    return 0;
}


/**
 * Getter for member Config.
 * @return Member Config.
 */
Config::Ptr Updater::get_config() const
{
    return Conf;
}


/**
 * Getter for member Logger.
 * @return Member Logger.
 */
Logger::Ptr Updater::get_logger() const
{
    return Log;
}


/**
 * Init the IPHelp member with needed values.
 * @return 0 if all is fine, -1 otherwise.
 */
int Updater::init_ip_helper()
{
    // initialize IPHelper
    IPHelper::Ptr _iphelp(new IPHelper(Log,Conf->get_webcheck_ip_url(),Conf->get_webcheck_ip_url_alt(),Conf->get_enable_ipv6(),Conf->get_proxy(),Conf->get_proxy_port()));
    IPHelp = _iphelp;
    _iphelp.reset();

    return 0;
}


/**
 * Reloading the config. Delete all Service objects and then init new Service objects from config files.
 */
int Updater::reload_config()
{
    // serialize all service objects
    if ( ServiceHolder->serialize_services() != 0 )
        return -1;

    // delete all service objects
    ServiceHolder->delete_services();

    // delete the actual Variables_map, perhaps with old cmd options which would overwrite new config file options.
    Conf->delete_variables_map();

    // load only config files
    if ( init_config_from_files() != 0 )
        return -1;

    return 0;
}


/**
 * Initialize the logging facility with loglevel and syslog.
 */
void Updater::init_log_facility()
{
    Log->set_log_facility(Conf->get_loglevel(),Conf->get_syslog());
    Log->print_init_log_facility();
}


/**
 * Update all configured services.
 */
void Updater::update_services()
{
    list<Service::Ptr> services = ServiceHolder->get_services();

    string ip = IPHelp->get_actual_ip();

    if ( !ip.empty() )
    {
        BOOST_FOREACH(Service::Ptr &service, services )
        {
            string dns_recheck_ip = ip;
            int current_time = time(NULL);

            int lastupdated = 0;
            if ( service->get_last_updates()->size() > 0 )
                lastupdated = service->get_last_updates()->front();

            // If the dns cache ttl is expired, then get the actual ip of the dns record (this should be the IP in the last update)
            if ( (lastupdated != 0) && ((lastupdated + service->get_dns_cache_ttl()) < current_time) )
            {
                Log->print_recheck_dns_entry(service->get_hostname(),lastupdated,service->get_dns_cache_ttl(),current_time);
                string _dns_recheck_ip = IPHelp->dns_query(service->get_hostname());
                Log->print_cached_dns_entry(service->get_hostname(), _dns_recheck_ip, service->get_actual_ip());
                if (!_dns_recheck_ip.empty())
                    dns_recheck_ip = _dns_recheck_ip;
            }

            // In case the local hosts IP (ip) differ from the IP set in the last update (actual_ip) or
            // the IP of the dns record (dns_recheck_ip) differs from the IP of the local host (ip)
            // then perform an update. This implies that the update is not performed if actual_ip == dns_recheck_ip.
            if ( (service->get_actual_ip() != ip) || (dns_recheck_ip != ip)  )
                service->update(ip,current_time);
        }
    }
}


/**
 * Getter for member ServiceHolder.
 * @return ServiceHolder
 */
Serviceholder::Ptr Updater::get_service_holder() const
{
    return ServiceHolder;
}