init

.gitignore

@@ -1,15 +1 @@
-# Binaries for programs and plugins
-*.exe
-*.exe~
-*.dll
-*.so
-*.dylib
-
-# Test binary, built with `go test -c`
-*.test
-
-# Output of the go coverage tool, specifically when used with LiteIDE
-*.out
-
-# Dependency directories (remove the comment below to include it)
-# vendor/
+.idea

README.md

@@ -1,2 +1,27 @@
-# ngr-emailer
-Tiny lib for email (with attachments) sending 
+# emailer
+Tiny lib for email (with attachments) sending (smtp)
+
+# import
+```import "github.com/NGRsoftlab/ngr-emailer"```
+
+# example
+```
+s := NewSender(
+		"[email protected]",
+		"password",
+		"[email protected]",
+		fmt.Sprintf("%v:%v", "test.com", "587"),
+	)
+
+	err := s.NewMessage("topic", []string{"[email protected]"}, "test", []AttachData{{
+		fileName: "test.txt",
+		fileData: []byte("test"),
+	}})
+	if err != nil {
+		log.Fatal(err)
+	}
+	err = s.Send()
+	if err != nil {
+		log.Fatal(err)
+	}
+```

emailer.go

@@ -0,0 +1,152 @@
+// Copyright 2020 NGR Softlab
+//
+package emailer
+
+import (
+	"bytes"
+	"encoding/base64"
+	"errors"
+	"fmt"
+	"github.com/NGRsoftlab/ngr-logging"
+	"mime/multipart"
+	"net/smtp"
+	"strings"
+	"time"
+)
+
+// Struct for auth.
+type loginAuth struct {
+	username, password string
+}
+
+// Struct for attachments.
+type AttachData struct {
+	FileName string
+	FileData []byte
+}
+
+// Auth with login and password.
+func LoginAuth(username, password string) smtp.Auth {
+	return &loginAuth{username, password}
+}
+
+// Login auth start.
+func (a *loginAuth) Start(server *smtp.ServerInfo) (string, []byte, error) {
+	return "LOGIN", []byte{}, nil
+}
+
+// Next loginAuth.
+func (a *loginAuth) Next(fromServer []byte, more bool) ([]byte, error) {
+	if more {
+		switch string(fromServer) {
+		case "Username:":
+			return []byte(a.username), nil
+		case "Password:":
+			return []byte(a.password), nil
+		default:
+			return nil, errors.New("Unknown fromServer")
+		}
+	}
+	return nil, nil
+}
+
+/////////////////////////////////////////////
+
+// Struct - sender for sending smtp packs.
+type Sender struct {
+	Login      string       // user login
+	Email      string       // user email address
+	Password   string       // user password
+	ServerSMTP string       // smtp server string
+	client     *smtp.Client // smtp client pointer
+	message    []byte       // message text
+	to         []string     // receivers of email
+}
+
+// Send smtp pack (mail).
+func (s *Sender) Send() error {
+	err := smtp.SendMail(s.ServerSMTP,
+		LoginAuth(s.Login, s.Password),
+		s.Login, s.to, s.message)
+
+	if err != nil {
+		logging.Logger.Error("SEND ERROR: ", err)
+		return err
+	}
+	return nil
+}
+
+/////////////////////////////////////////////
+
+// Creating new *Sender obj.
+func NewSender(login, password, email, server string) *Sender {
+	auth := Sender{
+		Login:      login,
+		Email:      email,
+		Password:   password,
+		ServerSMTP: server}
+	return &auth
+}
+
+// Creating new email message.
+func (s *Sender) NewMessage(subject string, to []string, body string, files []AttachData) error {
+	logging.Logger.Info("files: ", len(files))
+
+	attachments, err := attachFile(files)
+	if err != nil {
+		logging.Logger.Error(err)
+		return err
+	}
+
+	withAttachments := len(attachments) > 0
+	var headers = make(map[string]string)
+	headers["From"] = s.Email
+	headers["To"] = strings.Join(to, ";")
+	headers["Subject"] = subject
+	headers["MIME-Version"] = "1.0"
+	headers["Date"] = time.Now().Format(time.RFC1123Z)
+	var buf = bytes.NewBuffer(nil)
+	writer := multipart.NewWriter(buf)
+	boundary := writer.Boundary()
+
+	for k, v := range headers {
+		buf.WriteString(fmt.Sprintf("%s: %s\r\n", k, v))
+	}
+
+	if withAttachments {
+		buf.WriteString(fmt.Sprintf(`Content-Type: multipart/mixed; boundary="%s"`, boundary))
+		buf.WriteString("\r\n\r\n")
+		buf.WriteString(fmt.Sprintf("--%s\r\n", boundary))
+	}
+	buf.WriteString("Content-Type: text/plain; charset=utf-8\r\n")
+	buf.WriteString("MIME-Version: 1.0\r\n")
+	buf.WriteString("\r\n" + body)
+	if withAttachments {
+		for k, v := range attachments {
+			buf.WriteString(fmt.Sprintf("\r\n--%s\r\n", boundary))
+			buf.WriteString("Content-Type: application/vnd.openxmlformats-officedocument.spreadsheetml.sheet\r\n")
+			buf.WriteString("Content-Transfer-Encoding: base64\r\n")
+			buf.WriteString("MIME-Version: 1.0\r\n")
+			buf.WriteString(fmt.Sprintf(`Content-Disposition: attachment; filename="%s"`, k))
+			buf.WriteString("\r\n\r\n")
+
+			var b = make([]byte, base64.StdEncoding.EncodedLen(len(v)))
+			base64.StdEncoding.Encode(b, v)
+			buf.Write(b)
+		}
+		buf.WriteString("--")
+	}
+	s.to = to
+	s.message = buf.Bytes()
+
+	return nil
+}
+
+// Attaching file to mail. Returns attachments map: "filename": filedata.
+func attachFile(files []AttachData) (map[string][]byte, error) {
+	var attachments = make(map[string][]byte)
+	for _, f := range files {
+		attachments[f.FileName] = f.FileData
+	}
+	return attachments, nil
+}

emailer_test.go

@@ -0,0 +1,31 @@
+// Copyright 2020 NGR Softlab
+//
+package emailer
+
+import (
+	"fmt"
+	"testing"
+)
+
+/////////////////////////////////////////////////
+// Put correct here before testing.
+func TestSimpleMail(t *testing.T) {
+	s := NewSender(
+		"[email protected]",
+		"password",
+		"[email protected]",
+		fmt.Sprintf("%v:%v", "test.com", "587"),
+	)
+
+	err := s.NewMessage("topic", []string{"[email protected]"}, "test", []AttachData{{
+		FileName: "test.txt",
+		FileData: []byte("test"),
+	}})
+	if err != nil {
+		t.Fatal(err)
+	}
+	err = s.Send()
+	if err != nil {
+		t.Fatal(err)
+	}
+}

go.mod

@@ -0,0 +1,8 @@
+module github.com/NGRsoftlab/ngr-emailer
+
+go 1.13
+
+require (
+	github.com/NGRsoftlab/ngr-logging v1.0.0
+	github.com/sirupsen/logrus v1.8.1 // indirect
+)

go.sum

@@ -0,0 +1,12 @@
+github.com/NGRsoftlab/ngr-logging v1.0.0 h1:Yp42kvw/bofZ6xXC5jPlPx1HNabZQY9cvzGnB0earJY=
+github.com/NGRsoftlab/ngr-logging v1.0.0/go.mod h1:99kZ+XwSK7rKRitmhZvqOdYnPf9Qepywt3zjJJcJDME=
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
+github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/sirupsen/logrus v1.8.1 h1:dJKuHgqk1NNQlqoA6BTlM1Wf9DOH3NBjQyu0h9+AZZE=
+github.com/sirupsen/logrus v1.8.1/go.mod h1:yWOB1SBYBC5VeMP7gHvWumXLIWorT60ONWic61uBYv0=
+github.com/stretchr/testify v1.2.2 h1:bSDNvY7ZPG5RlJ8otE/7V6gMiyenm9RtJ7IUVIAoJ1w=
+github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXfy6kDkUVs=
+golang.org/x/sys v0.0.0-20191026070338-33540a1f6037 h1:YyJpGZS1sBuBCzLAR1VEpK193GlqGZbnPFnPV/5Rsb4=
+golang.org/x/sys v0.0.0-20191026070338-33540a1f6037/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=