To gitea and beyond, let's go(-yco)

internal/services/email_sender.go

@@ -0,0 +1,99 @@
+package services
+
+import (
+	"fmt"
+	"net/smtp"
+	"strings"
+	"time"
+)
+
+type EmailSender interface {
+	Send(to, subject, body string) error
+}
+
+type SMTPSender struct {
+	host     string
+	port     int
+	username string
+	password string
+	from     string
+	timeout  time.Duration
+}
+
+func NewSMTPSender(cfgHost string, cfgPort int, cfgUsername, cfgPassword, cfgFrom string) *SMTPSender {
+	return &SMTPSender{
+		host:     cfgHost,
+		port:     cfgPort,
+		username: cfgUsername,
+		password: cfgPassword,
+		from:     cfgFrom,
+		timeout:  30 * time.Second,
+	}
+}
+
+func NewSMTPSenderWithTimeout(cfgHost string, cfgPort int, cfgUsername, cfgPassword, cfgFrom string, timeout time.Duration) *SMTPSender {
+	return &SMTPSender{
+		host:     cfgHost,
+		port:     cfgPort,
+		username: cfgUsername,
+		password: cfgPassword,
+		from:     cfgFrom,
+		timeout:  timeout,
+	}
+}
+
+func (s *SMTPSender) Send(to, subject, body string) error {
+	if s == nil {
+		return fmt.Errorf("smtp sender is not configured")
+	}
+
+	to = strings.TrimSpace(to)
+	if to == "" {
+		return fmt.Errorf("recipient address is required")
+	}
+
+	address := fmt.Sprintf("%s:%d", s.host, s.port)
+
+	headers := []string{
+		fmt.Sprintf("From: %s", s.from),
+		fmt.Sprintf("To: %s", to),
+		fmt.Sprintf("Subject: %s", subject),
+		"MIME-Version: 1.0",
+		"Content-Type: text/html; charset=\"UTF-8\"",
+	}
+
+	message := strings.Join(headers, "\r\n") + "\r\n\r\n" + body + "\r\n"
+
+	var auth smtp.Auth
+	if strings.TrimSpace(s.username) != "" {
+		auth = smtp.PlainAuth("", s.username, s.password, s.host)
+	}
+
+	done := make(chan error, 1)
+	go func() {
+		done <- smtp.SendMail(address, auth, s.from, []string{to}, []byte(message))
+	}()
+
+	select {
+	case err := <-done:
+		return err
+	case <-time.After(s.timeout):
+		return fmt.Errorf("email sending timeout after %v", s.timeout)
+	}
+}
+
+func (s *SMTPSender) SendAsync(to, subject, body string) <-chan error {
+	result := make(chan error, 1)
+	go func() {
+		result <- s.Send(to, subject, body)
+	}()
+	return result
+}
+
+func (s *SMTPSender) SetTimeout(timeout time.Duration) {
+	if s == nil {
+		return
+	}
+
+	s.timeout = timeout
+}