h202-wq
@@ -0,0 +1,257 @@
|
||||
package email
|
||||
|
||||
import (
|
||||
"crypto/tls"
|
||||
"fmt"
|
||||
"math/rand"
|
||||
"net/mail"
|
||||
"net/smtp"
|
||||
"net/textproto"
|
||||
"strings"
|
||||
|
||||
"source.offmarket.win/aleagle/eaglecast/internal/utils"
|
||||
"source.offmarket.win/aleagle/eaglecast/models"
|
||||
"github.com/knadh/smtppool/v2"
|
||||
)
|
||||
|
||||
const (
|
||||
MessengerName = "email"
|
||||
|
||||
hdrReturnPath = "Return-Path"
|
||||
hdrBcc = "Bcc"
|
||||
hdrCc = "Cc"
|
||||
hdrMessageID = "Message-Id"
|
||||
)
|
||||
|
||||
// Server represents an SMTP server's credentials.
|
||||
type Server struct {
|
||||
// Name is a unique identifier for the server.
|
||||
Name string `json:"name"`
|
||||
Username string `json:"username"`
|
||||
Password string `json:"password"`
|
||||
AuthProtocol string `json:"auth_protocol"`
|
||||
TLSType string `json:"tls_type"`
|
||||
TLSSkipVerify bool `json:"tls_skip_verify"`
|
||||
EmailHeaders map[string]string `json:"email_headers"`
|
||||
FromAddresses []string `json:"from_addresses"`
|
||||
|
||||
// Rest of the options are embedded directly from the smtppool lib.
|
||||
// The JSON tag is for config unmarshal to work.
|
||||
//lint:ignore SA5008 ,squash is needed by koanf/mapstructure config unmarshal.
|
||||
smtppool.Opt `json:",squash"`
|
||||
|
||||
pool *smtppool.Pool
|
||||
}
|
||||
|
||||
// Emailer is the SMTP e-mail messenger.
|
||||
type Emailer struct {
|
||||
name string
|
||||
|
||||
// pools holds groups of SMTP servers indexed by a key ('from'-address
|
||||
// or a domain set per SMTPs server). An empty key holds all servers
|
||||
// and is the fallback round-robin when there's no match (old behaviour).
|
||||
pools map[string][]*Server
|
||||
}
|
||||
|
||||
// NormalizeAddr normalizes an e-mail address (strip spaces, lowercase).
|
||||
func NormalizeAddr(s string) string {
|
||||
return strings.ToLower(strings.TrimSpace(s))
|
||||
}
|
||||
|
||||
// New returns an SMTP e-mail Messenger backend with the given SMTP servers.
|
||||
// Group indicates whether the messenger represents a group of SMTP servers (1 or more)
|
||||
// that are used as a round-robin pool, or a single server.
|
||||
func New(name string, servers ...Server) (*Emailer, error) {
|
||||
e := &Emailer{
|
||||
name: name,
|
||||
pools: make(map[string][]*Server),
|
||||
}
|
||||
|
||||
for _, srv := range servers {
|
||||
s := srv
|
||||
|
||||
var auth smtp.Auth
|
||||
switch s.AuthProtocol {
|
||||
case "cram":
|
||||
auth = smtp.CRAMMD5Auth(s.Username, s.Password)
|
||||
case "plain":
|
||||
auth = smtp.PlainAuth("", s.Username, s.Password, s.Host)
|
||||
case "login":
|
||||
auth = &smtppool.LoginAuth{Username: s.Username, Password: s.Password}
|
||||
case "", "none":
|
||||
default:
|
||||
return nil, fmt.Errorf("unknown SMTP auth type '%s'", s.AuthProtocol)
|
||||
}
|
||||
s.Opt.Auth = auth
|
||||
|
||||
// TLS config.
|
||||
s.Opt.SSL = smtppool.SSLNone
|
||||
if s.TLSType != "none" {
|
||||
s.TLSConfig = &tls.Config{}
|
||||
if s.TLSSkipVerify {
|
||||
s.TLSConfig.InsecureSkipVerify = s.TLSSkipVerify
|
||||
} else {
|
||||
s.TLSConfig.ServerName = s.Host
|
||||
}
|
||||
|
||||
// SSL/TLS, not STARTTLS.
|
||||
switch s.TLSType {
|
||||
case "TLS":
|
||||
s.Opt.SSL = smtppool.SSLTLS
|
||||
case "STARTTLS":
|
||||
s.Opt.SSL = smtppool.SSLSTARTTLS
|
||||
}
|
||||
}
|
||||
|
||||
pool, err := smtppool.New(s.Opt)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
s.pool = pool
|
||||
|
||||
// Add to the global list (empty key) and to each from-address
|
||||
// bucket. Duplicate keys across servers are fine and get round-robin'd.
|
||||
e.pools[""] = append(e.pools[""], &s)
|
||||
for _, addr := range s.FromAddresses {
|
||||
if key := NormalizeAddr(addr); key != "" {
|
||||
e.pools[key] = append(e.pools[key], &s)
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
return e, nil
|
||||
}
|
||||
|
||||
// Name returns the messenger's name.
|
||||
func (e *Emailer) Name() string {
|
||||
return e.name
|
||||
}
|
||||
|
||||
// Push pushes a message to the server.
|
||||
func (e *Emailer) Push(m models.Message) error {
|
||||
// Pick the from-address-routed pool if there is one, else default
|
||||
// to the full pool (empty key) for roundrobin.
|
||||
pool := e.pools[""]
|
||||
if len(e.pools) > 1 {
|
||||
if srvs := e.getPool(m.From); srvs != nil {
|
||||
pool = srvs
|
||||
}
|
||||
}
|
||||
srv := pool[rand.Intn(len(pool))]
|
||||
|
||||
// Are there attachments?
|
||||
var files []smtppool.Attachment
|
||||
if m.Attachments != nil {
|
||||
files = make([]smtppool.Attachment, 0, len(m.Attachments))
|
||||
for _, f := range m.Attachments {
|
||||
a := smtppool.Attachment{
|
||||
Filename: f.Name,
|
||||
Header: f.Header,
|
||||
Content: make([]byte, len(f.Content)),
|
||||
HTMLRelated: f.IsInline,
|
||||
}
|
||||
copy(a.Content, f.Content)
|
||||
files = append(files, a)
|
||||
}
|
||||
}
|
||||
|
||||
// Create the email.
|
||||
em := smtppool.Email{
|
||||
From: m.From,
|
||||
To: m.To,
|
||||
Subject: m.Subject,
|
||||
Attachments: files,
|
||||
}
|
||||
|
||||
em.Headers = textproto.MIMEHeader{}
|
||||
|
||||
// Attach SMTP level headers.
|
||||
for k, v := range srv.EmailHeaders {
|
||||
em.Headers.Set(k, v)
|
||||
}
|
||||
|
||||
// Attach e-mail level headers.
|
||||
for k, v := range m.Headers {
|
||||
em.Headers.Set(k, v[0])
|
||||
}
|
||||
|
||||
// Generate Message-Id based on the From address.
|
||||
if em.Headers.Get(hdrMessageID) == "" {
|
||||
d := "localhost"
|
||||
if a, err := mail.ParseAddress(m.From); err == nil {
|
||||
d = a.Address[strings.LastIndex(a.Address, "@")+1:]
|
||||
}
|
||||
if r, err := utils.GenerateRandomString(24); err == nil {
|
||||
em.Headers.Set(hdrMessageID, fmt.Sprintf("<%s@%s>", r, d))
|
||||
}
|
||||
}
|
||||
|
||||
// If the `Return-Path` header is set, it should be set as the
|
||||
// the SMTP envelope sender (via the Sender field of the email struct).
|
||||
if sender := em.Headers.Get(hdrReturnPath); sender != "" {
|
||||
em.Sender = sender
|
||||
em.Headers.Del(hdrReturnPath)
|
||||
}
|
||||
|
||||
// If the `Bcc` header is set, it should be set on the Envelope
|
||||
if bcc := em.Headers.Get(hdrBcc); bcc != "" {
|
||||
for _, part := range strings.Split(bcc, ",") {
|
||||
em.Bcc = append(em.Bcc, strings.TrimSpace(part))
|
||||
}
|
||||
em.Headers.Del(hdrBcc)
|
||||
}
|
||||
|
||||
// If the `Cc` header is set, it should be set on the Envelope
|
||||
if cc := em.Headers.Get(hdrCc); cc != "" {
|
||||
for _, part := range strings.Split(cc, ",") {
|
||||
em.Cc = append(em.Cc, strings.TrimSpace(part))
|
||||
}
|
||||
em.Headers.Del(hdrCc)
|
||||
}
|
||||
|
||||
switch m.ContentType {
|
||||
case "plain":
|
||||
em.Text = []byte(m.Body)
|
||||
default:
|
||||
em.HTML = m.Body
|
||||
if len(m.AltBody) > 0 {
|
||||
em.Text = m.AltBody
|
||||
}
|
||||
}
|
||||
|
||||
return srv.pool.Send(em)
|
||||
}
|
||||
|
||||
// Flush flushes the message queue to the server.
|
||||
func (e *Emailer) Flush() error {
|
||||
return nil
|
||||
}
|
||||
|
||||
// Close closes the SMTP pools.
|
||||
func (e *Emailer) Close() error {
|
||||
for _, s := range e.pools[""] {
|
||||
s.pool.Close()
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
// getPool returns the pool of servers configured to handle the given From
|
||||
// header, matched by full e-mail and then by domain.
|
||||
// Returns nil if no mapping matches.
|
||||
func (e *Emailer) getPool(from string) []*Server {
|
||||
addr := utils.ParseEmailAddress(from)
|
||||
if addr == "" {
|
||||
return nil
|
||||
}
|
||||
|
||||
if srvs, ok := e.pools[addr]; ok {
|
||||
return srvs
|
||||
}
|
||||
|
||||
if _, after, ok := strings.Cut(addr, "@"); ok {
|
||||
return e.pools[after]
|
||||
}
|
||||
|
||||
return nil
|
||||
}
|
||||
Reference in New Issue
Block a user