protected override void ProcessRecord()
        {
            var logger = new PSLogger(Host);

            var zipFolder = Path.GetDirectoryName(MyInvocation.MyCommand.Module.Path);
            var installer = new UnattendInstaller(logger, zipFolder);

            foreach (var name in Name)
            {
                var options = new InstanceUpgradeOptions {
                    AuditRetentionPeriod = AuditRetentionPeriod, ErrorRetentionPeriod = ErrorRetentionPeriod, OverrideEnableErrorForwarding = ForwardErrorMessages
                };
                var instance = ServiceControlInstance.FindByName(name);
                if (instance == null)
                {
                    WriteWarning($"No action taken. An instance called {name} was not found");
                    break;
                }

                options.OverrideEnableErrorForwarding = ForwardErrorMessages;


                // Migrate Value
                if (!options.AuditRetentionPeriod.HasValue)
                {
                    if (instance.AppSettingExists(SettingsList.HoursToKeepMessagesBeforeExpiring.Name))
                    {
                        var i = instance.ReadAppSetting(SettingsList.HoursToKeepMessagesBeforeExpiring.Name, -1);
                        if (i != -1)
                        {
                            options.AuditRetentionPeriod = TimeSpan.FromHours(i);
                        }
                    }
                }

                if (!options.OverrideEnableErrorForwarding.HasValue & !instance.AppSettingExists(SettingsList.ForwardErrorMessages.Name))
                {
                    ThrowTerminatingError(new ErrorRecord(new Exception($"Upgrade of {instance.Name} aborted. ForwardErrorMessages parameter must be set to true or false because the configuration file has no setting for ForwardErrorMessages. This setting is mandatory as of version 1.12"), "UpgradeFailure", ErrorCategory.InvalidArgument, null));
                }

                if (!options.ErrorRetentionPeriod.HasValue & !instance.AppSettingExists(SettingsList.ErrorRetentionPeriod.Name))
                {
                    ThrowTerminatingError(new ErrorRecord(new Exception($"Upgrade of {instance.Name} aborted. ErrorRetentionPeriod parameter must be set to timespan because the configuration file has no setting for ErrorRetentionPeriod. This setting is mandatory as of version 1.13"), "UpgradeFailure", ErrorCategory.InvalidArgument, null));
                }

                if (!options.AuditRetentionPeriod.HasValue & !instance.AppSettingExists(SettingsList.AuditRetentionPeriod.Name))
                {
                    ThrowTerminatingError(new ErrorRecord(new Exception($"Upgrade of {instance.Name} aborted. AuditRetentionPeriod parameter must be set to timespan because the configuration file has no setting for AuditRetentionPeriod. This setting is mandatory as of version 1.13"), "UpgradeFailure", ErrorCategory.InvalidArgument, null));
                }

                if (!installer.Upgrade(instance, options))
                {
                    ThrowTerminatingError(new ErrorRecord(new Exception($"Upgrade of {instance.Name} failed"), "UpgradeFailure", ErrorCategory.InvalidResult, null));
                }
            }
        }
        public void UpgradeInstance()
        {
            var installer = new UnattendInstaller(new TestLogger(), deploymentCache);

            foreach (var instance in ServiceControlInstance.Instances())  //.Where(p => p.Name.StartsWith("Test.ServiceControl", StringComparison.OrdinalIgnoreCase)))
            {
                installer.Upgrade(instance, new InstanceUpgradeOptions {
                    AuditRetentionPeriod = TimeSpan.FromDays(30), ErrorRetentionPeriod = TimeSpan.FromDays(15), OverrideEnableErrorForwarding = true
                });
            }
        }
        static void UpgradeInstances(Session session, ServiceControlZipInfo zipInfo, MSILogger logger, UnattendInstaller unattendedInstaller)
        {
            var options = new InstanceUpgradeOptions();

            var upgradeInstancesPropertyValue = session["UPGRADEINSTANCES"];

            if (string.IsNullOrWhiteSpace(upgradeInstancesPropertyValue))
            {
                return;
            }
            upgradeInstancesPropertyValue = upgradeInstancesPropertyValue.Trim();

            var forwardErrorMessagesPropertyValue = session["FORWARDERRORMESSAGES"];

            try
            {
                options.OverrideEnableErrorForwarding = bool.Parse(forwardErrorMessagesPropertyValue);
            }
            catch
            {
                options.OverrideEnableErrorForwarding = null;
            }

            var auditRetentionPeriodPropertyValue = session["AUDITRETENTIONPERIOD"];

            try
            {
                options.AuditRetentionPeriod = TimeSpan.Parse(auditRetentionPeriodPropertyValue);
            }
            catch
            {
                options.AuditRetentionPeriod = null;
            }

            var errorRetentionPeriodPropertyValue = session["ERRORRETENTIONPERIOD"];

            try
            {
                options.ErrorRetentionPeriod = TimeSpan.Parse(errorRetentionPeriodPropertyValue);
            }
            catch
            {
                options.ErrorRetentionPeriod = null;
            }

            //determine what to upgrade
            var instancesToUpgrade = new List <ServiceControlInstance>();

            if (upgradeInstancesPropertyValue.Equals("*", StringComparison.OrdinalIgnoreCase) || upgradeInstancesPropertyValue.Equals("ALL", StringComparison.OrdinalIgnoreCase))
            {
                instancesToUpgrade.AddRange(ServiceControlInstance.Instances());
            }
            else
            {
                var candidates = upgradeInstancesPropertyValue.Replace(" ", String.Empty).Split(",".ToCharArray(), StringSplitOptions.RemoveEmptyEntries);
                instancesToUpgrade.AddRange(ServiceControlInstance.Instances().Where(instance => candidates.Contains(instance.Name, StringComparer.OrdinalIgnoreCase)));
            }

            // do upgrades
            foreach (var instance in instancesToUpgrade)
            {
                if (zipInfo.Version > instance.Version)
                {
                    if (!instance.AppSettingExists(SettingsList.ForwardErrorMessages.Name) & !options.OverrideEnableErrorForwarding.Value)
                    {
                        logger.Warn($"Unattend upgrade {instance.Name} to {zipInfo.Version} not attempted. FORWARDERRORMESSAGES MSI parameter was required because appsettings needed a value for '{SettingsList.ForwardErrorMessages.Name}'");
                        continue;
                    }


                    if (!options.AuditRetentionPeriod.HasValue)
                    {
                        if (!instance.AppSettingExists(SettingsList.AuditRetentionPeriod.Name))
                        {
                            //Try migration first
                            if (instance.AppSettingExists(SettingsList.HoursToKeepMessagesBeforeExpiring.Name))
                            {
                                var i = instance.ReadAppSetting(SettingsList.HoursToKeepMessagesBeforeExpiring.Name, -1);
                                if (i > 0)
                                {
                                    options.AuditRetentionPeriod = TimeSpan.FromHours(i);
                                }
                            }
                            else
                            {
                                logger.Warn($"Unattend upgrade {instance.Name} to {zipInfo.Version} not attempted. AUDITRETENTIONPERIOD MSI parameter was required because appsettings needed a value for '{SettingsList.AuditRetentionPeriod.Name}'");
                                continue;
                            }
                        }
                    }

                    if (!instance.AppSettingExists(SettingsList.ErrorRetentionPeriod.Name) & !options.ErrorRetentionPeriod.HasValue)
                    {
                        logger.Warn($"Unattend upgrade {instance.Name} to {zipInfo.Version} not attempted. ERRORRETENTIONPERIOD MSI parameter was required because appsettings needed a value for '{SettingsList.ErrorRetentionPeriod.Name}'");
                        continue;
                    }

                    if (!unattendedInstaller.Upgrade(instance, options))
                    {
                        logger.Warn($"Failed to upgrade {instance.Name} to {zipInfo.Version}");
                    }
                }
            }
        }