private async Task SendAlertsForJobSet(IJobsDataProvider jobsProvider, JobsSet jobsSet, int?frequency, JobAlertSettings alertSettings, bool forceResend)
        {
            // No point sending alerts without links to the jobs
            if (alertSettings.JobAdvertBaseUrl == null)
            {
                _log.Error("JobAdvertBaseUrl not found - aborting");
                return;
            }

            // We need somewhere to get the alerts from...
            var converter = new JobSearchQueryConverter(ConfigurationManager.AppSettings["TranslateObsoleteJobTypes"]?.ToUpperInvariant() == "TRUE");
            var encoder   = new JobAlertIdEncoder(converter);
            IJobAlertsRepository alertsRepo = new AzureTableStorageAlertsRepository(converter, ConfigurationManager.ConnectionStrings["JobAlerts.AzureStorage"].ConnectionString);

            // We need a way to send the alerts...
            var configuration = new ConfigurationServiceRegistry();
            var emailService  = ServiceContainer.LoadService <IEmailSender>(configuration);
            var sender        = new JobAlertsByEmailSender(alertSettings, new HtmlJobAlertFormatter(alertSettings, encoder), emailService);

            // Get them, sort them and send them
            _log.Info($"Requesting jobs matching {jobsSet} with frequency {frequency} from Azure Storage");
            var alerts = await alertsRepo.GetAlerts(new JobAlertsQuery()
            {
                Frequency = frequency, JobsSet = jobsSet
            });

            var alertsGroupedByEmail = GroupAlertsByEmail(alerts);

            _log.Info($"{alerts.Count()} alerts found for {alertsGroupedByEmail.Count()} email addresses");
            foreach (var alertsForAnEmail in alertsGroupedByEmail)
            {
                foreach (var alert in alertsForAnEmail)
                {
                    var jobsSentForThisEmail = forceResend ? new List <int>() : await alertsRepo.GetJobsSentForEmail(alert.JobsSet, alert.Email);
                    await LookupJobsForAlert(jobsProvider, alert, jobsSentForThisEmail);
                }
            }

            _log.Info("Sending alerts");
            await sender.SendGroupedAlerts(alertsGroupedByEmail, alertsRepo);
        }