README
¶
Go Simple Mail
The best way to send emails in Go with SMTP Keep Alive and Timeout for Connect and Send.
IMPORTANT
Examples in this README are for v2.2.0 and above. Examples for older versions can be found here.
The minimum Go version is 1.13, for Go 1.12 and older use branch go1.12.
Breaking change in 2.2.0: The signature of SetBody and AddAlternative used
to accept strings ("text/html" and "text/plain") and not require on of the
contentType constants (TextHTML or TextPlain). Upgrading, while not
quite following semantic versioning, is quite simple:
email := mail.NewMSG()
- email.SetBody("text/html", htmlBody)
- email.AddAlternative("text/plain", plainBody)
+ email.SetBody(mail.TextHTML, htmlBody)
+ email.AddAlternative(mail.TextPlain, plainBody)
Introduction
Go Simple Mail is a simple and efficient package to send emails. It is well tested and documented.
Go Simple Mail can only send emails using an SMTP server. But the API is flexible and it is easy to implement other methods for sending emails using a local Postfix, an API, etc.
This package contains (and is based on) two packages by Joe Grasse:
- https://github.com/joegrasse/mail (unmaintained since Jun 29, 2018), and
- https://github.com/joegrasse/mime (unmaintained since Oct 1, 2015).
A lot of changes in Go Simple Mail were sent with not response.
Features
Go Simple Mail supports:
- Multiple Attachments with path
- Multiple Attachments in base64
- Multiple Recipients
- Priority
- Reply to
- Set other sender
- Set other from
- Embedded images
- HTML and text templates
- Automatic encoding of special characters
- SSL and TLS
- Unencrypted connection (not recommended)
- Sending multiple emails with the same SMTP connection (Keep Alive or Persistent Connection)
- Timeout for connect to a SMTP Server
- Timeout for send an email
- Return Path
- Alternative Email Body
- CC and BCC
- Add Custom Headers in Message
- Send NOOP, RESET, QUIT and CLOSE to SMTP client
- PLAIN, LOGIN and CRAM-MD5 Authentication (since v2.3.0)
- Custom TLS Configuration (since v2.5.0)
Documentation
https://pkg.go.dev/github.com/xhit/go-simple-mail/v2?tab=doc
Download
This package uses go modules.
$ go get github.com/xhit/go-simple-mail/v2
Usage
package main
import (
"log"
"github.com/xhit/go-simple-mail/v2"
)
const htmlBody = `<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>Hello Gophers!</title>
</head>
<body>
<p>This is the <b>Go gopher</b>.</p>
<p><img src="cid:Gopher.png" alt="Go gopher" /></p>
<p>Image created by Renee French</p>
</body>
</html>`
func main() {
server := mail.NewSMTPClient()
// SMTP Server
server.Host = "smtp.example.com"
server.Port = 587
server.Username = "test@example.com"
server.Password = "examplepass"
server.Encryption = mail.EncryptionTLS
// Since v2.3.0 you can specified authentication type:
// - PLAIN (default)
// - LOGIN
// - CRAM-MD5
// server.Authentication = mail.AuthPlain
// Variable to keep alive connection
server.KeepAlive = false
// Timeout for connect to SMTP Server
server.ConnectTimeout = 10 * time.Second
// Timeout for send the data and wait respond
server.SendTimeout = 10 * time.Second
// Set TLSConfig to provide custom TLS configuration. For example,
// to skip TLS verification (useful for testing):
server.TLSConfig = &tls.Config{InsecureSkipVerify: true}
// SMTP client
smtpClient,err := server.Connect()
if err != nil{
log.Fatal(err)
}
// New email simple html with inline and CC
email := mail.NewMSG()
email.SetFrom("From Example <nube@example.com>").
AddTo("xhit@example.com").
AddCc("otherto@example.com").
SetSubject("New Go Email")
email.SetBody(mail.TextHTML, htmlBody)
email.AddInline("/path/to/image.png", "Gopher.png")
// Call Send and pass the client
err = email.Send(smtpClient)
if err != nil {
log.Println(err)
} else {
log.Println("Email Sent")
}
}
Send multiple emails in same connection
//Set your smtpClient struct to keep alive connection
server.KeepAlive = true
for _, to := range []string{
"to1@example1.com",
"to3@example2.com",
"to4@example3.com",
} {
// New email simple html with inline and CC
email := mail.NewMSG()
email.SetFrom("From Example <nube@example.com>").
AddTo(to).
SetSubject("New Go Email")
email.SetBody(mail.TextHTML, htmlBody)
email.AddInline("/path/to/image.png", "Gopher.png")
// Call Send and pass the client
err = email.Send(smtpClient)
if err != nil {
log.Println(err)
} else {
log.Println("Email Sent")
}
}
More examples
Documentation
¶
Index ¶
- Constants
- type Email
- func (email *Email) AddAddresses(header string, addresses ...string) *Email
- func (email *Email) AddAlternative(contentType contentType, body string) *Email
- func (email *Email) AddAttachment(file string, name ...string) *Email
- func (email *Email) AddAttachmentBase64(b64File string, name string) *Email
- func (email *Email) AddAttachmentReader(r io.Reader, name string) *Email
- func (email *Email) AddBcc(addresses ...string) *Email
- func (email *Email) AddCc(addresses ...string) *Email
- func (email *Email) AddHeader(header string, values ...string) *Email
- func (email *Email) AddHeaders(headers textproto.MIMEHeader) *Email
- func (email *Email) AddInline(file string, name ...string) *Email
- func (email *Email) AddInlineReader(r io.Reader, name string) *Email
- func (email *Email) AddTo(addresses ...string) *Email
- func (email *Email) GetError() error
- func (email *Email) GetFrom() string
- func (email *Email) GetMessage() string
- func (email *Email) Send(client *SMTPClient) error
- func (email *Email) SetBody(contentType contentType, body string) *Email
- func (email *Email) SetDate(dateTime string) *Email
- func (email *Email) SetFrom(address string) *Email
- func (email *Email) SetPriority(priority priority) *Email
- func (email *Email) SetReplyTo(address string) *Email
- func (email *Email) SetReturnPath(address string) *Email
- func (email *Email) SetSender(address string) *Email
- func (email *Email) SetSubject(subject string) *Email
- type SMTPClient
- type SMTPServer
Constants ¶
const ( // EncryptionNone uses no encryption when sending email EncryptionNone encryption = iota // EncryptionSSL sets encryption type to SSL when sending email EncryptionSSL // EncryptionTLS sets encryption type to TLS when sending email EncryptionTLS )
const ( // EncodingNone turns off encoding on the message body EncodingNone encoding = iota // EncodingBase64 sets the message body encoding to base64 EncodingBase64 // EncodingQuotedPrintable sets the message body encoding to quoted-printable EncodingQuotedPrintable )
const ( // TextPlain sets body type to text/plain in message body TextPlain contentType = iota // TextHTML sets body type to text/html in message body TextHTML )
const ( // AuthPlain implements the PLAIN authentication AuthPlain authType = iota // AuthLogin implements the LOGIN authentication AuthLogin // AuthCRAMMD5 implements the CRAM-MD5 authentication AuthCRAMMD5 )
const ( // PriorityLow sets the email priority to Low PriorityLow priority = iota // PriorityHigh sets the email priority to High PriorityHigh )
Variables ¶
This section is empty.
Functions ¶
This section is empty.
Types ¶
type Email ¶
type Email struct {
Charset string
Encoding encoding
Error error
SMTPServer *smtpClient
// contains filtered or unexported fields
}
Email represents an email message.
func NewMSG ¶
func NewMSG() *Email
NewMSG creates a new email. It uses UTF-8 by default. All charsets: http://webcheatsheet.com/HTML/character_sets_list.php
func (*Email) AddAddresses ¶
AddAddresses allows you to add addresses to the specified address header.
func (*Email) AddAlternative ¶
AddAlternative allows you to add alternative parts to the body of the email message. This is most commonly used to add an html version in addition to a plain text version that was already added with SetBody.
func (*Email) AddAttachment ¶
AddAttachment allows you to add an attachment to the email message. You can optionally provide a different name for the file.
func (*Email) AddAttachmentBase64 ¶
AddAttachmentBase64 allows you to add an attachment in base64 to the email message. You need provide a name for the file.
func (*Email) AddAttachmentReader ¶
AddAttachmentReader allows you to add an attachment from a io.Reader to the email message. You need provide a name for the file.
func (*Email) AddBcc ¶
AddBcc adds a Bcc address. You can provide multiple addresses at the same time.
func (*Email) AddHeaders ¶
func (email *Email) AddHeaders(headers textproto.MIMEHeader) *Email
AddHeaders is used to add multiple headers at once
func (*Email) AddInline ¶
AddInline allows you to add an inline attachment to the email message. You can optionally provide a different name for the file.
func (*Email) AddInlineReader ¶
AddInlineReader allows you to add an inline attachment from a io.Reader to the email message. You need provide a name for the file.
func (*Email) GetMessage ¶
GetMessage builds and returns the email message
func (*Email) Send ¶
func (email *Email) Send(client *SMTPClient) error
Send sends the composed email
func (*Email) SetDate ¶
SetDate sets the date header to the provided date/time. The format of the string should be YYYY-MM-DD HH:MM:SS Time Zone.
Example: SetDate("2015-04-28 10:32:00 CDT")
func (*Email) SetPriority ¶
SetPriority sets the email message priority. Use with either "High" or "Low".
func (*Email) SetReplyTo ¶
SetReplyTo sets the Reply-To address.
func (*Email) SetReturnPath ¶
SetReturnPath sets the Return-Path address. This is most often used to send bounced emails to a different email address.
func (*Email) SetSubject ¶
SetSubject sets the subject of the email message.
type SMTPClient ¶
SMTPClient represents a SMTP Client for send email
func (*SMTPClient) Noop ¶
func (smtpClient *SMTPClient) Noop() error
Noop send NOOP command to smtp client
func (*SMTPClient) Quit ¶
func (smtpClient *SMTPClient) Quit() error
Quit send QUIT command to smtp client
func (*SMTPClient) Reset ¶
func (smtpClient *SMTPClient) Reset() error
Reset send RSET command to smtp client
type SMTPServer ¶
type SMTPServer struct {
Authentication authType
Encryption encryption
Username string
Password string
ConnectTimeout time.Duration
SendTimeout time.Duration
Host string
Port int
KeepAlive bool
TLSConfig *tls.Config
}
SMTPServer represents a SMTP Server If authentication is CRAM-MD5 then the Password is the Secret
func NewSMTPClient ¶
func NewSMTPClient() *SMTPServer
NewSMTPClient returns the client for send email
func (*SMTPServer) Connect ¶
func (server *SMTPServer) Connect() (*SMTPClient, error)
Connect returns the smtp client
Source Files