Mail Sending

Mail sending is performed from the Server project, for example from a controller or server service. It is not possible to send an email directly from the Client project.

Configure an SMTP server

The Lagoon:Smtp section in the appsettings.json file configures the ISmtp service.

warning

The Sender key defines the default sender and must be set if application calls do not explicitly provide a sender.

{
  "Lagoon": {
    "Smtp": {
      "Host": "smtp.provider.com",
      "Port": 587,
      "EnableSSL": true,
      "UserName": "username",
      "Password": "smtpPassword",
      "Sender": "app@desirade.fr",
      "CheckCertificateRevocation": true
    }
  }
}

CheckCertificateRevocation is optional. It can be set to false if a certificate revocation verification error occurs. The actual reverse option is IgnoreCertificateRevocation.

Lagoon:Smtp Options

Option	Type	Default	Description
Host	string	null	SMTP server address.
Port	int	0	SMTP server port.
SecureSocketMode	SecureSocketOptions	Auto	SSL/TLS mode used by MailKit.
EnableSSL	bool	Inferred from SecureSocketMode	Configuration compatibility: false forces SecureSocketMode to None, true resets it to Auto if it was None.
UserName	string	null	Identifier used to authenticate to the SMTP server.
Password	string	null	SMTP password.
Sender	string	null	Default sender address.
CheckCertificateRevocation	bool	true	Indicates whether the client verifies certificate revocation.
IgnoreCertificateRevocation	bool	false	Disables certificate revocation verification.
ContentTransfertEncoding	ContentEncoding	Base64	MIME content encoding.
LogFile	string	null	Path to the SMTP protocol log file, or Console.
LogToConsole	bool	false	Writes the SMTP protocol log to the console by setting LogFile to Console.
MailMode	string	SMTP	SMTP for direct sending, Daemon for writing mail files to a folder.
MailDaemonFolder	string	null	Folder used in Daemon mode.
MailDaemonEncoding	string	iso-8859-1 if absent	Encoding used to save Daemon mode files.
UseDaemonFolder	bool	false	Enables the use of daemon folder.

Daemon folder mode

Daemon mode saves emails to a folder instead of sending them directly via SMTP.

{
  "Lagoon": {
    "Smtp": {
      "MailMode": "Daemon",
      "MailDaemonFolder": "C:\\Temp\\PendingMails",
      "Sender": "app@desirade.fr"
    }
  }
}

Register the service

In the Server project, register the service via AddSmtp().

Server/Services/Registry.cs

public static class Registry
{
    public static void RegisterServices(IServiceCollection services)
    {
        // Activates the server-side mail sending service.
        services.AddSmtp();
    }
}

Send an email from a controller

TasksController.cs

[ApiController]
[Route("api/[controller]")]
public class TasksController : LgControllerBase
{
    private readonly ISmtp _smtp;

    public TasksController(ISmtp smtp)
    {
        _smtp = smtp;
    }

    [Authorize(Roles = AppRoles.Admin)]
    [HttpPost("CreateTask")]
    public async Task Create(UserTask task)
    {
        // Creates the user task.

        // Sends an email after task creation.
        await _smtp.SendEmailAsync(
            "admin@provider.com",
            "New task created",
            "Hello,<br />A new task has been created.");
    }
}

Recipients and attachments

ISmtp exposes overloads for:

• a single recipient or multiple recipients IEnumerable<string>;
• a list of carbon copy cc recipients;
• attachments as file paths, byte[], or Stream;
• an explicit sender or the default Sender.

To send to multiple recipients in a single string, separate addresses with commas.