package vain import ( "bytes" "fmt" "net/mail" "net/smtp" ) // A Mailer is a type that knows how to send smtp mail. type Mailer interface { Send(to mail.Address, subject, msg string) error } // NewEmail returns *Email struct to be able to send smtp // or an error if it can't correctly parse the email address. func NewEmail(from, host string, port int) (*Email, error) { if _, err := mail.ParseAddress(from); err != nil { return nil, fmt.Errorf("can't parse an email address for 'from': %v", err) } r := &Email{ host: host, port: port, from: from, } return r, nil } // Email stores information required to use smtp. type Email struct { host string port int from string } // Send sends a smtp email using the host and port in the Email struct and //returns an error if there was a problem sending the email. func (e Email) Send(to mail.Address, subject, msg string) error { c, err := smtp.Dial(fmt.Sprintf("%s:%d", e.host, e.port)) if err != nil { return fmt.Errorf("couldn't dial mail server: %v", err) } defer c.Close() if err := c.Mail(e.from); err != nil { return err } if err := c.Rcpt(to.String()); err != nil { return err } wc, err := c.Data() if err != nil { return fmt.Errorf("problem sending mail: %v", err) } buf := bytes.NewBufferString("Subject: " + subject + "\n\n" + msg) buf.WriteTo(wc) if err := c.Quit(); err != nil { return nil } return err } type mockMail struct { msg string } func (m *mockMail) Send(to mail.Address, subject, msg string) error { m.msg = msg return nil }