feat: WIP auth mailing implementation

adapters/secondary/gateways/mailRepository.go

@@ -0,0 +1,57 @@
+package gateways
+
+import (
+	"GohCMS2/domain/gateways"
+	"bytes"
+	"embed"
+	"gopkg.in/gomail.v2"
+	"html/template"
+	"log"
+	"os"
+	"strconv"
+)
+
+type MailRepository struct{}
+
+//go:embed mail/templates/*
+var mailTemplateFiles embed.FS
+
+func (m MailRepository) Send(receiverAddress string, templateName string, data interface{}) error {
+	from := os.Getenv("SMTP_EMAIL")
+	password := os.Getenv("SMTP_PASSWORD")
+	smtpHost := os.Getenv("SMTP_HOST")
+	smtpPort, _ := strconv.Atoi(os.Getenv("SMTP_PORT"))
+
+	d := gomail.NewDialer(smtpHost, smtpPort, from, password)
+
+	tmpl, err := template.ParseFS(mailTemplateFiles, "mail/templates/"+templateName+".html")
+	if err != nil {
+		log.Println("error when template.ParseFS:", err)
+		return err
+	}
+
+	var body bytes.Buffer
+	err = tmpl.Execute(&body, data)
+	if err != nil {
+		log.Println("error when tmpl.Execute:", err)
+		return err
+	}
+
+	msg := gomail.NewMessage()
+	msg.SetHeader("From", "GohCMS <"+from+">")
+	msg.SetHeader("To", receiverAddress)
+	msg.SetHeader("MIME-version", "1.0")
+	msg.SetHeader("Content-Type", "text/html")
+	msg.SetHeader("charset", "UTF-8")
+	msg.SetHeader("Subject", "GohCMS | Action required")
+	msg.SetBody("text/html", body.String())
+
+	if err := d.DialAndSend(msg); err != nil {
+		log.Println("error when sending email:", err)
+		return err
+	}
+
+	return nil
+}
+
+var _ gateways.IMailRepository = &MailRepository{}