Initial commit

email/main.go

@@ -0,0 +1,56 @@
+// Package email handles the sending of emails
+package email
+
+import (
+	"bytes"
+	"fmt"
+	"github.com/uberswe/golang-base-project/config"
+	"github.com/uberswe/golang-base-project/util"
+	"log"
+	"mime/multipart"
+	"net/smtp"
+	"strings"
+)
+
+type Service struct {
+	Config config.Config
+}
+
+func New(c config.Config) Service {
+	return Service{
+		Config: c,
+	}
+}
+
+func (s Service) Send(to string, subject string, message string) {
+	// Authentication.
+	auth := smtp.PlainAuth("", s.Config.SMTPUsername, s.Config.SMTPPassword, s.Config.SMTPHost)
+
+	// RFC #822 Standard
+	writer := multipart.NewWriter(bytes.NewBufferString(""))
+	var b bytes.Buffer
+	_, _ = fmt.Fprintf(&b, "From: %s\r\nTo: %s\r\nSubject: %s\r\n", s.Config.SMTPSender, to, subject)
+	_, _ = fmt.Fprintf(&b, "MIME-Version: 1.0\r\n")
+	_, _ = fmt.Fprintf(&b, "Content-Type: multipart/alternative; charset=\"UTF-8\"; boundary=\"%s\"\r\n", writer.Boundary())
+	_, _ = fmt.Fprintf(&b, "\r\n\r\n--%s\r\nContent-Type: %s; charset=UTF-8;\nContent-Transfer-Encoding: 8bit\r\n\r\n", writer.Boundary(), "text/plain")
+	b.Write([]byte(message))
+	htmlMessage := util.StringLinkToHTMLLink(message)
+	htmlMessage = util.NL2BR(htmlMessage)
+	_, _ = fmt.Fprintf(&b, "\r\n\r\n--%s\r\nContent-Type: %s; charset=UTF-8;\nContent-Transfer-Encoding: 8bit\r\n\r\n", writer.Boundary(), "text/html")
+	b.Write([]byte(htmlMessage))
+
+	_, _ = fmt.Fprintf(&b, "\r\n\r\n--%s--\r\n", writer.Boundary())
+
+	sender := s.Config.SMTPSender
+	if strings.Contains(sender, "<") {
+		sender = util.GetStringBetweenStrings(sender, "<", ">")
+	}
+
+	// Sending email.
+	err := smtp.SendMail(fmt.Sprintf("%s:%s", s.Config.SMTPHost, s.Config.SMTPPort), auth, sender, []string{to}, b.Bytes())
+	if err != nil {
+		log.Println(err)
+		return
+	}
+	log.Println(fmt.Sprintf("Email sent to %s", to))
+}