Scalr\Modules\Platforms\Openstack\OpenstackPlatformModule::GetServerAvailZone PHP Method

    private function GetServerAvailZone(DBServer $DBServer, OpenStack $client, \Scalr_Server_LaunchOptions $launchOptions)
    {
        if ($DBServer->status == \SERVER_STATUS::TEMPORARY) {
            return null;
        }
        $serverAvailZone = $DBServer->GetProperty(\OPENSTACK_SERVER_PROPERTIES::CLOUD_LOCATION_ZONE);
        if ($serverAvailZone && $serverAvailZone != 'x-scalr-diff' && !stristr($serverAvailZone, "x-scalr-custom")) {
            return $serverAvailZone;
        }
        $roleAvailZone = $DBServer->GetFarmRoleObject()->GetSetting(Entity\FarmRoleSetting::OPENSTACK_AVAIL_ZONE);
        if (!$roleAvailZone) {
            return null;
        }
        if ($roleAvailZone == "x-scalr-diff" || stristr($roleAvailZone, "x-scalr-custom")) {
            $availZones = array();
            if (stristr($roleAvailZone, "x-scalr-custom")) {
                $zones = explode("=", $roleAvailZone);
                foreach (explode(":", $zones[1]) as $zoneName) {
                    if ($zoneName != "") {
                        $isUnavailable = $DBServer->GetEnvironmentObject()->getPlatformConfigValue("openstack.{$launchOptions->cloudLocation}.{$zoneName}.unavailable", false);
                        if ($isUnavailable && $isUnavailable + 3600 < time()) {
                            $DBServer->GetEnvironmentObject()->setPlatformConfig(array("openstack.{$launchOptions->cloudLocation}.{$zoneName}.unavailable" => false), false);
                            $isUnavailable = false;
                        }
                        if (!$isUnavailable) {
                            array_push($availZones, $zoneName);
                        }
                    }
                }
            } else {
                // Get list of all available zones
                $availZonesResp = $client->servers->listAvailabilityZones();
                foreach ($availZonesResp as $zone) {
                    $zoneName = $zone->zoneName;
                    if ($zone->zoneState->available == true) {
                        $isUnavailable = $DBServer->GetEnvironmentObject()->getPlatformConfigValue("openstack.{$launchOptions->cloudLocation}.{$zoneName}.unavailable", false);
                        if ($isUnavailable && $isUnavailable + 3600 < time()) {
                            $DBServer->GetEnvironmentObject()->setPlatformConfig(array("openstack.{$launchOptions->cloudLocation}.{$zoneName}.unavailable" => false), false);
                            $isUnavailable = false;
                        }
                        if (!$isUnavailable) {
                            array_push($availZones, $zoneName);
                        }
                    }
                }
            }
            rsort($availZones);
            $availZone = null;
            $servers = $DBServer->GetFarmRoleObject()->GetServersByFilter(array("status" => array(\SERVER_STATUS::RUNNING, \SERVER_STATUS::INIT, \SERVER_STATUS::PENDING)));
            $availZoneDistribution = array();
            foreach ($servers as $cDbServer) {
                if ($cDbServer->serverId != $DBServer->serverId) {
                    $availZoneDistribution[$cDbServer->GetProperty(\OPENSTACK_SERVER_PROPERTIES::CLOUD_LOCATION_ZONE)]++;
                }
            }
            $sCount = PHP_INT_MAX;
            foreach ($availZones as $zone) {
                if ((int) $availZoneDistribution[$zone] <= $sCount) {
                    $sCount = (int) $availZoneDistribution[$zone];
                    $availZone = $zone;
                }
            }
            return $availZone;
        } else {
            return $roleAvailZone;
        }
    }