/
smtp.go
72 lines (68 loc) · 1.37 KB
/
smtp.go
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package main
import (
"crypto/tls"
"fmt"
"net/smtp"
"time"
)
func SendMail(timeout time.Duration, addr string, from string, to string, msg []byte) error {
response := make(chan error, 1)
var conn *smtp.Client
var err error
go func() {
conn, err = smtp.Dial(addr)
if err != nil {
response <- err
return
}
response <- nil
}()
select {
case res := <-response:
if res == nil {
go func() {
defer conn.Close()
if err = conn.Hello("localhost"); err != nil {
response <- err
return
}
if ok, _ := conn.Extension("STARTTLS"); ok {
config := &tls.Config{ServerName: addr}
if err = conn.StartTLS(config); err != nil {
response <- err
return
}
}
if err = conn.Mail(from); err != nil {
response <- err
return
}
if err = conn.Rcpt(to); err != nil {
response <- err
return
}
w, err := conn.Data()
if err != nil {
response <- err
return
}
_, err = w.Write(msg)
if err != nil {
response <- err
return
}
err = w.Close()
if err != nil {
response <- err
return
}
response <- conn.Quit()
}()
return <-response
} else {
return res
}
case <-time.After(time.Second * timeout): //don't do the smtp transaction, abandon the socket, it'll timeout after ~3 mins in syn_sent
return fmt.Errorf("Sending timeout")
}
}