Add test mail command (#571)

Add test mail command

Co-authored-by: kolaente <k@knt.li>
Reviewed-on: https://kolaente.dev/vikunja/api/pulls/571

pkg/mail/mail.go

@@ -27,6 +27,16 @@ import (
 // Queue is the mail queue
 var Queue chan *gomail.Message
 
+func getDialer() *gomail.Dialer {
+	d := gomail.NewDialer(config.MailerHost.GetString(), config.MailerPort.GetInt(), config.MailerUsername.GetString(), config.MailerPassword.GetString())
+	// #nosec
+	d.TLSConfig = &tls.Config{
+		InsecureSkipVerify: config.MailerSkipTLSVerify.GetBool(),
+		ServerName:         config.MailerHost.GetString(),
+	}
+	return d
+}
+
 // StartMailDaemon starts the mail daemon
 func StartMailDaemon() {
 	Queue = make(chan *gomail.Message, config.MailerQueuelength.GetInt())
@@ -41,9 +51,7 @@ func StartMailDaemon() {
 	}
 
 	go func() {
-		d := gomail.NewDialer(config.MailerHost.GetString(), config.MailerPort.GetInt(), config.MailerUsername.GetString(), config.MailerPassword.GetString())
-		// #nosec
-		d.TLSConfig = &tls.Config{InsecureSkipVerify: config.MailerSkipTLSVerify.GetBool()}
+		d := getDialer()
 
 		var s gomail.SendCloser
 		var err error

pkg/mail/send_mail.go

@@ -53,6 +53,30 @@ type header struct {
 	Content string
 }
 
+// SendTestMail sends a test mail to a receipient.
+// It works without a queue.
+func SendTestMail(to string) error {
+	if config.MailerHost.GetString() == "" {
+		log.Warning("Mailer seems to be not configured! Please see the config docs for more details.")
+		return nil
+	}
+
+	d := getDialer()
+	s, err := d.Dial()
+	if err != nil {
+		return err
+	}
+	defer s.Close()
+
+	m := gomail.NewMessage()
+	m.SetHeader("From", config.MailerFromEmail.GetString())
+	m.SetHeader("To", to)
+	m.SetHeader("Subject", "Test from Vikunja")
+	m.SetBody("text/plain", "This is a test mail! If you got this, Vikunja is correctly set up to send emails.")
+
+	return gomail.Send(s, m)
+}
+
 // SendMail puts a mail in the queue
 func SendMail(opts *Opts) {
 	m := gomail.NewMessage()