111 lines
2.4 KiB
Go
111 lines
2.4 KiB
Go
package messenger
|
|
|
|
import (
|
|
"fmt"
|
|
"math/rand"
|
|
"net/smtp"
|
|
"time"
|
|
|
|
"github.com/jordan-wright/email"
|
|
)
|
|
|
|
const emName = "email"
|
|
|
|
// Server represents an SMTP server's credentials.
|
|
type Server struct {
|
|
Name string
|
|
Host string `koanf:"host"`
|
|
Port int `koanf:"port"`
|
|
AuthProtocol string `koanf:"auth_protocol"`
|
|
Username string `koanf:"username"`
|
|
Password string `koanf:"password"`
|
|
SendTimeout time.Duration `koanf:"send_timeout"`
|
|
MaxConns int `koanf:"max_conns"`
|
|
|
|
mailer *email.Pool
|
|
}
|
|
|
|
type emailer struct {
|
|
servers map[string]*Server
|
|
serverNames []string
|
|
numServers int
|
|
}
|
|
|
|
// NewEmailer creates and returns an e-mail Messenger backend.
|
|
// It takes multiple SMTP configurations.
|
|
func NewEmailer(srv ...Server) (Messenger, error) {
|
|
e := &emailer{
|
|
servers: make(map[string]*Server),
|
|
}
|
|
|
|
for _, s := range srv {
|
|
var auth smtp.Auth
|
|
if s.AuthProtocol == "cram" {
|
|
auth = smtp.CRAMMD5Auth(s.Username, s.Password)
|
|
} else {
|
|
auth = smtp.PlainAuth("", s.Username, s.Password, s.Host)
|
|
}
|
|
|
|
pool, err := email.NewPool(fmt.Sprintf("%s:%d", s.Host, s.Port), s.MaxConns, auth)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
s.mailer = pool
|
|
e.servers[s.Name] = &s
|
|
e.serverNames = append(e.serverNames, s.Name)
|
|
}
|
|
|
|
e.numServers = len(e.serverNames)
|
|
return e, nil
|
|
}
|
|
|
|
// Name returns the Server's name.
|
|
func (e *emailer) Name() string {
|
|
return emName
|
|
}
|
|
|
|
// Push pushes a message to the server.
|
|
func (e *emailer) Push(fromAddr string, toAddr []string, subject string, m []byte, atts []*Attachment) error {
|
|
var key string
|
|
|
|
// If there are more than one SMTP servers, send to a random
|
|
// one from the list.
|
|
if e.numServers > 1 {
|
|
key = e.serverNames[rand.Intn(e.numServers)]
|
|
} else {
|
|
key = e.serverNames[0]
|
|
}
|
|
|
|
// Are there attachments?
|
|
var files []*email.Attachment
|
|
if atts != nil {
|
|
files = make([]*email.Attachment, 0, len(atts))
|
|
for _, f := range atts {
|
|
a := &email.Attachment{
|
|
Filename: f.Name,
|
|
Header: f.Header,
|
|
Content: make([]byte, len(f.Content)),
|
|
}
|
|
copy(a.Content, f.Content)
|
|
files = append(files, a)
|
|
}
|
|
}
|
|
|
|
srv := e.servers[key]
|
|
err := srv.mailer.Send(&email.Email{
|
|
From: fromAddr,
|
|
To: toAddr,
|
|
Subject: subject,
|
|
HTML: m,
|
|
Attachments: files,
|
|
}, srv.SendTimeout)
|
|
|
|
return err
|
|
}
|
|
|
|
// Flush flushes the message queue to the server.
|
|
func (e *emailer) Flush() error {
|
|
return nil
|
|
}
|