refactor a bit

cmd/cmd.go

@@ -143,7 +143,7 @@ func initSMTP(cfg *config.Config) {
 		MaxSize:     cfg.MaxSize,
 		Bot:         mxb,
 		Callers:     []smtp.Caller{mxb, q},
-		Relay: smtp.RelayConfig{
+		Relay: &smtp.RelayConfig{
 			Host:     cfg.Relay.Host,
 			Port:     cfg.Relay.Port,
 			Usename:  cfg.Relay.Username,

smtp/client.go

@@ -14,21 +14,31 @@ type MailSender interface {
 	Send(from string, to string, data string) error
 }
 
+// SMTP client
 type Client struct {
 	config *RelayConfig
 	log    *logger.Logger
 }
 
-func newClient(cfg *RelayConfig, log *logger.Logger) Client {
-	return Client{
+func newClient(cfg *RelayConfig, log *logger.Logger) *Client {
+	return &Client{
 		config: cfg,
 		log:    log,
 	}
 }
 
+// Send email
 func (c Client) Send(from string, to string, data string) error {
 	c.log.Debug("Sending email from %s to %s", from, to)
-	conn, err := c.createSmtpClient(from, to)
+
+	var conn *smtp.Client
+	var err error
+	if c.config.Host != "" {
+		conn, err = c.createDirectClient(from, to)
+	} else {
+		conn, err = trysmtp.Connect(from, to)
+	}
+
 	if conn == nil {
 		c.log.Error("cannot connect to SMTP server of %s: %v", to, err)
 		return err
@@ -56,19 +66,11 @@ func (c Client) Send(from string, to string, data string) error {
 	return nil
 }
 
-func (c *Client) createSmtpClient(from string, to string) (*smtp.Client, error) {
-	if c.config.Host != "" {
-		return c.createDirectClient(from, to)
-	}
-
-	return trysmtp.Connect(from, to)
-}
-
+// createDirectClient connects directly to the provided smtp host
 func (c *Client) createDirectClient(from string, to string) (*smtp.Client, error) {
 	localname := strings.SplitN(from, "@", 2)[1]
 	target := c.config.Host + ":" + c.config.Port
 	conn, err := smtp.Dial(target)
-
 	if err != nil {
 		return nil, err
 	}

smtp/manager.go

@@ -29,7 +29,7 @@ type Config struct {
 	MaxSize  int
 	Bot      matrixbot
 	Callers  []Caller
-	Relay    RelayConfig
+	Relay    *RelayConfig
 }
 
 type TLSConfig struct {
@@ -79,17 +79,14 @@ type Caller interface {
 // NewManager creates new SMTP server manager
 func NewManager(cfg *Config) *Manager {
 	log := logger.New("smtp.", cfg.LogLevel)
-
-	smtpClient := newClient(&cfg.Relay, log)
-
 	mailsrv := &mailServer{
-		log:        log,
-		bot:        cfg.Bot,
-		domains:    cfg.Domains,
-		mailSender: smtpClient,
+		log:     log,
+		bot:     cfg.Bot,
+		domains: cfg.Domains,
+		sender:  newClient(cfg.Relay, log),
 	}
 	for _, caller := range cfg.Callers {
-		caller.SetSendmail(mailsrv.SendEmail)
+		caller.SetSendmail(mailsrv.sender.Send)
 	}
 
 	s := smtp.NewServer(mailsrv)

smtp/server.go

@@ -26,10 +26,10 @@ var (
 )
 
 type mailServer struct {
-	bot        matrixbot
-	log        *logger.Logger
-	domains    []string
-	mailSender MailSender
+	bot     matrixbot
+	log     *logger.Logger
+	domains []string
+	sender  MailSender
 }
 
 // Login used for outgoing mail submissions only (when you use postmoogle as smtp server in your scripts)
@@ -54,7 +54,7 @@ func (m *mailServer) Login(state *smtp.ConnectionState, username, password strin
 
 	return &outgoingSession{
 		ctx:       sentry.SetHubOnContext(context.Background(), sentry.CurrentHub().Clone()),
-		sendmail:  m.SendEmail,
+		sendmail:  m.sender.Send,
 		privkey:   m.bot.GetDKIMprivkey(),
 		from:      username,
 		log:       m.log,
@@ -87,11 +87,6 @@ func (m *mailServer) AnonymousLogin(state *smtp.ConnectionState) (smtp.Session,
 	}, nil
 }
 
-// SendEmail to external mail server
-func (m *mailServer) SendEmail(from, to, data string) error {
-	return m.mailSender.Send(from, to, data)
-}
-
 // ReceiveEmail - incoming mail into matrix room
 func (m *mailServer) ReceiveEmail(ctx context.Context, eml *email.Email) error {
 	return m.bot.IncomingEmail(ctx, eml)