Block service for a short period of time on too many update errors

[bpdyndnsd] / src / service.cpp

/** @file
 * @brief The abstract service class. This class represents all services.
 *
 *
 *
 * @copyright Intra2net AG
 * @license GPLv2
*/

#include "service.hpp"
#include <boost/foreach.hpp>

using namespace std;

/// Number of update errors until a service will be blocked
const int MaxErrorCount = 3;
/// Number of seconds a service will be blocked if MaxErrorCount is reached
const int ErrorBlockServiceSeconds = 15 * 60;

/**
 * Default Constructor
 */
Service::Service()
    : Login("NOT SERIALIZED")
    , Password("NOT SERIALIZED")
    , ActualIP("0.0.0.0")
    , UpdateInterval(0)
    , MaxUpdatesWithinInterval(0)
    , DNSCacheTTL(0)
    , ErrorCount(0)
    , ErrorServiceBlockedUntil(0)
    , Log(new Logger())
{
}


/**
 * Default Destructor needed for deserialization.
 */
Service::~Service()
{
}


/**
 * Setter for member Protocol.
 * @param _protocol Value to set Protocol to.
 */
void Service::set_protocol(const string& _protocol)
{
    Protocol = _protocol;
}


/**
 * Getter for memeber Protocol.
 * @return Value of member Protocol.
 */
string Service::get_protocol() const
{
    return Protocol;
}


/**
 * Setter for member Hostname.
 * @param _hostname Value to set Hostname to.
 */
void Service::set_hostname(const string& _hostname)
{
    Hostname = _hostname;
}


/**
 * Getter for member Hostname.
 * @return Value of member Hostname.
 */
string Service::get_hostname() const
{
    return Hostname;
}


/**
 * Setter for member Login.
 * @param _login Value to set Login to.
 */
void Service::set_login(const string& _login)
{
    Login = _login;
}


/**
 * Getter for member Login.
 * @return Value of member Login.
 */
string Service::get_login() const
{
    return Login;
}


/**
 * Setter for member Password.
 * @param _password Value to set Password to.
 */
void Service::set_password(const string& _password)
{
    Password = _password;
}


/**
 * Getter for member Password.
 * @return Value of member Password.
 */
string Service::get_password() const
{
    return Password;
}



void Service::set_logger(const Logger::Ptr& _log)
{
    Log = _log;
}


/**
 * Getter for member Log.
 * @return Shared pointer to Logger object.
 */
Logger::Ptr Service::get_logger() const
{
    return Log;
}


void Service::set_last_updates(std::list<time_t> _last_updates)
{
    LastUpdates.clear();
    BOOST_FOREACH( time_t update_time, _last_updates )
    {
        LastUpdates.push_back(update_time);
    }
}


/**
 * Getter for member Lastupdated.
 * @return Value of member Lastupdated.
 */
const list<time_t> Service::get_last_updates() const
{
    return LastUpdates;
}


/**
 * Setter for member ActualIP.
 * @param _actual_ip Value to set ActualIP to.
 */
void Service::set_actual_ip(const std::string& _actual_ip)
{
    ActualIP = _actual_ip;
}


/**
 * Getter for member ActualIP.
 * @return Value of member ActualIP.
 */
std::string Service::get_actual_ip() const
{
    return ActualIP;
}



/**
 * Overloading of comparison operator.
 * @param other Reference to other Service object.
 * @return True if they equal, false if not.
 */
bool Service::operator== (const Service& other) const
{
    if ( ( this->Protocol == other.Protocol ) && ( this->Hostname == other.Hostname ) )
        return true;
    return false;
}


/**
 * Overloading of disparate operator.
 * @param other Reference to other Service object.
 * @return True if they differ, false if they are equal.
 */
bool Service::operator!= (const Service& other) const
{
    return !(*this == other);
}


/**
 * Checks if update will exceed max update interval.
 * @param current_time Current time.
 * @return True if update is allowed, false if update would exceed max update interval.
 */
bool Service::update_allowed(const time_t current_time)
{
    list<time_t>::iterator iter;
    int i=0;

    for (iter = LastUpdates.begin(); (iter != LastUpdates.end()) && ( i < MaxUpdatesWithinInterval ); iter++)
    {
        if ( (i == (MaxUpdatesWithinInterval-1)) && ( (*iter + ((time_t)UpdateInterval*60)) >= current_time ) )
        {
            Log->print_update_not_allowed(current_time,*iter,MaxUpdatesWithinInterval,get_service_name());
            return false;
        }
        i++;
    }
    return true;
}


/**
 * Service update method, common to each service.
 * @param ip The new ip to set for the hostname.
 */
void Service::update(const string& ip, const time_t current_time)
{
    const std::string service_name = get_service_name();

    // Check if service is blocked for a short period of time (because of update errors)
    if (ErrorServiceBlockedUntil && current_time < ErrorServiceBlockedUntil)
    {
        Log->print_update_service_is_blocked(service_name, ErrorServiceBlockedUntil - current_time);
        return;
    }

    Log->print_update_service(service_name);

    // test if update is permitted by UpdateInterval Status
    if ( update_allowed(current_time) )
    {
        if ( perform_update(ip) == 0 )
        {
            // if update was successful, we need to set the Lastupdated and ActualIP base member.
            set_last_update(current_time);
            ActualIP = ip;
            Log->print_update_service_successful(service_name);

            ErrorCount = 0;
            ErrorServiceBlockedUntil = 0;
        }
        else
        {
            // problem while trying to update service
            Log->print_update_service_failure(service_name);

            ++ErrorCount;
            if (ErrorCount >= MaxErrorCount)
            {
                Log->print_block_service(service_name, ErrorBlockServiceSeconds);

                ErrorServiceBlockedUntil = time(NULL) + ErrorBlockServiceSeconds;
                ErrorCount = 0;
            }
        }
    }
}


/**
* Sets the given time into the LastUpdates member and deletes expired entries.
* @param _timeout Value to set into LastUpdates.
*/
void Service::set_last_update(const time_t current_time)
{
    // Insert value into the list.
    LastUpdates.push_front(current_time);

    // Check for expired entries:

    // MaxUpdatesWithinInterval given in service config, then use this to check for expired entries.
    if ( MaxUpdatesWithinInterval > 0 )
    {
        // Delete the oldest entry if there are more than MaxUpdatesWithinInterval+1 entries in the list.
        if (LastUpdates.size() > (MaxUpdatesWithinInterval+1))
            LastUpdates.pop_back();
        return;
    }
    // UpdateInterval given in service config, then use this to check for expired entries.
    else if ( UpdateInterval > 0 )
    {
        // Delete the oldest entry if it's older than current_time - UpdateInterval(minutes) + 1.
        if ( (current_time - ((time_t)UpdateInterval*60) + 1) > LastUpdates.back() )
            LastUpdates.pop_back();
        return;
    }
    // Neither MaxUpdatesWithinInterval nor UpdateInterval are given, so keep fix number of 10 entries.
    else
    {
        if ( LastUpdates.size() > 10 )
            LastUpdates.pop_back();
        return;
    }
}


/**
 * Setter for member Timeout.
 * @param _timeout Value to set Timeout to.
 */
void Service::set_update_interval(const int _update_interval)
{
    UpdateInterval = _update_interval;
}


/**
 * Getter for member Timeout.
 * @return Value of Timeout.
 */
int Service::get_update_interval() const
{
    return UpdateInterval;
}


/**
 * Setter for member Max_updates_per_timeout.
 * @param  _max_updates_per_timeout Value to set Max_updates_per_timeout to.
 */
void Service::set_max_updates_within_interval(const int _max_updates_within_interval)
{
    MaxUpdatesWithinInterval = _max_updates_within_interval;
}


/**
 * Getter for member Max_updates_per_timeout.
 * @return Value of Max_updates_per_timeout.
 */
int Service::get_max_updates_within_interval() const
{
    return MaxUpdatesWithinInterval;
}


/**
 * Get a unique service identify string
 * @return A unique service identify string
 */
string Service::get_service_name() const
{
    string service_name;

    service_name.append(Protocol);
    service_name.append(" ");
    service_name.append(Hostname);

    return service_name;
}


/**
 * Get member DNSCacheTTL
 * @return DNSCacheTTL
 */
int Service::get_dns_cache_ttl() const
{
    return DNSCacheTTL;
}


/**
 * Set member DNSCacheTTL
 * @param _dns_cache_ttl DNSCacheTTL
 */
void Service::set_dns_cache_ttl(const int _dns_cache_ttl)
{
    DNSCacheTTL = _dns_cache_ttl;
}