private bool IsNotObsolete(EmailMassSendingTaskItem item)
{
if (item.AttemptsLeft == 0)
{
return(false);
}
if (item.WaitFor != null && DateTimeOffset.Compare(item.WaitFor.Value, DateTimeOffset.UtcNow) > 0)
{
return(false);
}
if (DateTimeOffset.Compare(item.Lifetime, DateTimeOffset.UtcNow) < 0)
{
return(false);
}
return(true);
}
private async Task ProcessTaskItemAsync(EmailMassSendingTaskContext context,
EmailMassSendingTaskItem item, CancellationToken cancellationToken)
{
item.AttemptsLeft--;
item.Attempt = DateTimeOffset.UtcNow;
var defaultEncoding = _configuration.Encoding == null
? Encoding.UTF8
: Encoding.GetEncoding(_configuration.Encoding);
var encoding = context.GroupConfiguration.Encoding == null
? defaultEncoding
: Encoding.GetEncoding(context.GroupConfiguration.Encoding);
//using var client = new SmtpClient()
var scope = _logger.BeginScope(context.TaskId);
if (_configuration.SmtpClient.Enable ?? true)
{
try
{
using var client = new SmtpClient();
client.Host = _configuration.SmtpClient.Host;
client.Port = _configuration.SmtpClient.Port ?? 25;
client.EnableSsl = _configuration.SmtpClient.UseSsl ?? true;
client.DeliveryMethod = SmtpDeliveryMethod.Network;
client.UseDefaultCredentials = false;
client.Credentials =
new NetworkCredential(_configuration.SmtpClient.Username, _configuration.SmtpClient.Password);
using var message = new MailMessage();
message.From = new MailAddress(_configuration.FromAddress, _configuration.FromTitle,
defaultEncoding);
message.BodyEncoding = encoding;
message.SubjectEncoding = encoding;
message.IsBodyHtml = false;
message.Body = encoding.GetString(context.Text);
message.Subject = context.GroupConfiguration.Subject;
message.To.Add(new MailAddress(item.Receiver));
var ts = DateTime.UtcNow;
await client.SendMailAsync(message, cancellationToken);
_logger.LogDebug(
$"Mail to `{item.Receiver}` sent ({DateTime.UtcNow.Subtract(ts).TotalSeconds} s).");
item.Failed = false;
item.Failure = null;
}
catch (Exception e)
{
_logger.LogError(e,
$"Email sending error (item receiver: `{item.Receiver}`)");
item.Failed = true;
item.Failure = e.Message;
item.WaitFor = DateTimeOffset.UtcNow.Add(_configuration.RollUpStrategy.Delay);
}
}
else
{
item.Failed = false;
item.Failure = "Not sent (disabled)";
}
}
private bool IsReadyToProcess(EmailMassSendingTaskItem item)
{
return((item.Attempt == null || (item.Attempt != null && item.Failed)) && IsNotObsolete(item));
}
private async Task <EmailMassSendingTaskContext> PrepareGroupOfTasksAsync(string groupId,
GroupConfiguration groupConfiguration, bool force, CancellationToken cancellationToken)
{
await using var file = new FileStream(groupConfiguration.PlainTextFileName, FileMode.Open, FileAccess.Read,
FileShare.None);
var buffer = new byte[file.Length];
await file.ReadAsync(buffer, 0, buffer.Length, cancellationToken);
using var md5 = MD5.Create();
var hex = Convert.ToHexString(md5.ComputeHash(buffer));
var taskDir = _configuration.TasksPath ?? string.Empty;
var taskId = $"{groupId}_{hex}.task";
var taskPath = Path.Combine(taskDir, taskId);
if (!Directory.Exists(taskDir))
{
Directory.CreateDirectory(taskDir);
}
else
{
if (_configuration.DeleteObsoleteTasks)
{
var lifetime = _configuration.TaskFileLifetime ?? TimeSpan.FromDays(1);
foreach (var taskFileForDelete in Directory.GetFiles(taskDir, "*.task", SearchOption.TopDirectoryOnly))
{
var fi = new FileInfo(taskFileForDelete);
if (DateTime.Compare(fi.CreationTimeUtc.Add(lifetime), DateTime.UtcNow) < 0)
{
File.Delete(taskFileForDelete);
_logger.LogDebug($"Task file `{taskFileForDelete}` was deleted as obsolete.");
}
}
}
}
if (File.Exists(taskPath))
{
if (!force)
{
_logger.LogDebug($"Task `{taskId}` already exists. Reusing.");
var taskFs = new FileStream(taskPath, FileMode.Open, FileAccess.ReadWrite,
FileShare.None);
return(new EmailMassSendingTaskContext(taskId, taskFs, buffer, groupConfiguration));
}
File.Delete(taskPath);
}
var newTask = new EmailMassSendingTask
{
TaskId = taskId,
Items = new List <EmailMassSendingTaskItem>()
};
if (groupConfiguration.Receivers == null)
{
_logger.LogWarning($"No receivers in group `{groupId}` specified.");
return(null);
}
foreach (var receiver in groupConfiguration.Receivers.Distinct())
{
var newTaskItem = new EmailMassSendingTaskItem
{
Receiver = receiver,
Failed = false,
Failure = null,
Lifetime =
new DateTimeOffset(DateTime.UtcNow.Add(groupConfiguration.Actuality ?? TimeSpan.FromHours(1)))
};
if (_configuration.RollUpStrategy.Enable)
{
newTaskItem.AttemptsLeft = _configuration.RollUpStrategy.MaxCount;
newTaskItem.WaitFor = DateTimeOffset.UtcNow;
}
newTask.Items.Add(newTaskItem);
}
var task2Fs = new FileStream(taskPath, FileMode.CreateNew, FileAccess.ReadWrite,
FileShare.None);
var taskFileBody = Encoding.UTF8.GetBytes(JsonConvert.SerializeObject(newTask));
task2Fs.Position = 0;
task2Fs.SetLength(taskFileBody.Length);
await task2Fs.WriteAsync(taskFileBody, 0, taskFileBody.Length, cancellationToken);
task2Fs.Position = 0;
return(new EmailMassSendingTaskContext(taskId, task2Fs, buffer, groupConfiguration));
}
