switch to plain net/smtp

mailer.go

@@ -4,18 +4,15 @@ import (
 	"bytes"
 	"fmt"
 	"html/template"
+	"net/smtp"
 
 	"github.com/spf13/viper"
-	"github.com/wneessen/go-mail"
 )
 
 type Mailer struct {
 	TemplatesDir    string
 	TemplatesConfig *viper.Viper
-	SMTPConfig
-}
 
-type SMTPConfig struct {
 	From     string
 	Host     string
 	Port     int
@@ -23,98 +20,71 @@ type SMTPConfig struct {
 	Password string
 }
 
-type Option func(*mail.Msg, []mail.Option) ([]mail.Option, error)
-
 func NewMailer(templates_dir string, tplcfg *viper.Viper, smtpconfig *viper.Viper) (*Mailer, error) {
+	var (
+		from     = smtpconfig.GetString("from")
+		host     = smtpconfig.GetString("host")
+		port     = smtpconfig.GetInt("port")
+		username = smtpconfig.GetString("username")
+		password = smtpconfig.GetString("password")
+	)
+
 	return &Mailer{
 		TemplatesDir:    templates_dir,
 		TemplatesConfig: tplcfg,
-		SMTPConfig: SMTPConfig{
-			From:     smtpconfig.GetString("from"),
-			Host:     smtpconfig.GetString("host"),
-			Port:     smtpconfig.GetInt("port"),
-			Username: smtpconfig.GetString("username"),
-			Password: smtpconfig.GetString("password"),
-		},
+		From:            from,
+		Host:            host,
+		Port:            port,
+		Username:        username,
+		Password:        password,
 	}, nil
 }
 
-func (m *Mailer) Send(emailcfg string, to string, data any, opts ...Option) error {
+func (m *Mailer) Send(emailcfg string, to string, data any) error {
 	cfg := m.TemplatesConfig.Sub(emailcfg)
+	subject := cfg.GetString("subject")
 
 	files := cfg.GetStringSlice("files")
+
+	auth := smtp.PlainAuth("", m.Username, m.Password, m.Host)
+
+	var body bytes.Buffer
+
+	mimeHeaders := "MIME-version: 1.0;\nContent-Type: text/html; charset=\"UTF-8\";\n\n"
+	body.Write([]byte(fmt.Sprintf("Subject: %s \n%s\n\n", subject, mimeHeaders)))
+
+	if err := executeTemplate(&body, files, data, m.TemplatesDir); err != nil {
+		return fmt.Errorf("failed executing email template : %w", err)
+	}
+
+	smtpserver := fmt.Sprintf("%s:%d", m.Host, m.Port)
+
+	err := smtp.SendMail(smtpserver, auth, m.From, []string{to}, body.Bytes())
+	if err != nil {
+		return fmt.Errorf("isser sending email: %w", err)
+	}
+
+	return nil
+}
+
+func executeTemplate(body *bytes.Buffer, files []string, data any, templatesdir string) error {
 	prefixed_files := []string{}
 	for _, f := range files {
-		prefixed_files = append(prefixed_files, m.TemplatesDir+f)
+		prefixed_files = append(prefixed_files, templatesdir+f)
 	}
+
 	t := template.New("email").Funcs(
 		template.FuncMap{
 			"unescapeHTML": UnescapeHTML,
 		},
 	)
 	t = template.Must(t.ParseFiles(prefixed_files...))
-	buf := new(bytes.Buffer)
-	if err := t.ExecuteTemplate(buf, "main", data); err != nil {
+	if err := t.ExecuteTemplate(body, "main", data); err != nil {
 		return fmt.Errorf("failed execute mail template : %w", err)
 	}
-	body := buf.String()
-
-	message := mail.NewMsg()
-	fromAddress := m.SMTPConfig.From
-	if fromAddress == "" {
-		fromAddress = m.SMTPConfig.Username
-	}
-
-	fmt.Println("From : ", fromAddress)
-
-	if err := message.From(m.SMTPConfig.From); err != nil {
-		return fmt.Errorf("failed to set From header : %w", err)
-	}
-	if err := message.To(to); err != nil {
-		return fmt.Errorf("failed to set To header : %w", err)
-	}
-	message.Subject(cfg.GetString("subject"))
-	message.SetBodyString(mail.TypeTextHTML, body)
-
-	dialOptions := []mail.Option{
-		mail.WithSMTPAuth(mail.SMTPAuthAutoDiscover),
-		mail.WithTLSPolicy(mail.TLSOpportunistic),
-		// mail.WithSMTPAuth(mail.SMTPAuthNoAuth),
-		mail.WithUsername(m.SMTPConfig.Username),
-		mail.WithPassword(m.SMTPConfig.Password),
-		mail.WithPort(m.SMTPConfig.Port),
-	}
-
-	fmt.Println(dialOptions)
-
-	for _, opt := range opts {
-		no, err := opt(message, dialOptions)
-		if err != nil {
-			return fmt.Errorf("failed to set option : %w", err)
-		}
-		dialOptions = no
-	}
-
-	fmt.Println(dialOptions)
-
-	client, err := mail.NewClient(m.SMTPConfig.Host, dialOptions...)
-	if err != nil {
-		return fmt.Errorf("failed to create mail client : %w", err)
-	}
-
-	if err := client.DialAndSend(message); err != nil {
-		return fmt.Errorf("failed to send message : %w", err)
-	}
-
 	return nil
 }
 
-func WithReplyTo(email string) Option {
-	return func(m *mail.Msg, opts []mail.Option) ([]mail.Option, error) {
-		return opts, m.ReplyTo(email)
-	}
-}
-
 func UnescapeHTML(s string) template.HTML {
 	return template.HTML(s)
 }