begin work on mailing list server, got the fundamental components done

1 files changed, 75 insertions, 0 deletions

diff --git a/srv/mailinglist/mailer.go b/srv/mailinglist/mailer.go
new file mode 100644
index 0000000..81d0b91
--- /dev/null
+++ b/srv/mailinglist/mailer.go
@@ -0,0 +1,75 @@
+package mailinglist
+
+import (
+	"github.com/emersion/go-sasl"
+	"github.com/emersion/go-smtp"
+)
+
+// Mailer is used to deliver emails to arbitrary recipients.
+type Mailer interface {
+	Send(to, subject, body string) error
+}
+
+// MailerParams are used to initialize a new Mailer instance
+type MailerParams struct {
+	SMTPAddr string
+
+	// Optional, if not given then no auth is attempted.
+	SMTPAuth sasl.Client
+
+	// The sending email address to use for all emails being sent.
+	SendAs string
+}
+
+type mailer struct {
+	params MailerParams
+}
+
+// NewMailer initializes and returns a Mailer which will use an external SMTP
+// server to deliver email.
+func NewMailer(params MailerParams) Mailer {
+	return &mailer{
+		params: params,
+	}
+}
+
+func (m *mailer) Send(to, subject, body string) error {
+
+	msg := []byte("From: " + m.params.SendAs + "\r\n" +
+		"To: " + to + "\r\n" +
+		"Subject: " + subject + "\r\n\r\n" +
+		body + "\r\n")
+
+	c, err := smtp.Dial(m.params.SMTPAddr)
+	if err != nil {
+		return err
+	}
+	defer c.Close()
+
+	if err = c.Auth(m.params.SMTPAuth); err != nil {
+		return err
+	}
+
+	if err = c.Mail(m.params.SendAs, nil); err != nil {
+		return err
+	}
+
+	if err = c.Rcpt(to); err != nil {
+		return err
+	}
+
+	w, err := c.Data()
+	if err != nil {
+		return err
+	}
+
+	if _, err = w.Write(msg); err != nil {
+		return err
+	}
+
+	if err = w.Close(); err != nil {
+		return err
+	}
+
+	return c.Quit()
+}