added go-dkim package and List-Unsubscribe header to the project (#54)

* added go-dkim package to the project * updated readme for dkim and unsubscribe examples * Removed privatekey because the parameter is not needed * requested changes for dkim and list-unsubscribe adding
xhit · Dec 21, 2021 · 780823a · 780823a
1 parent c20e8ef
commit 780823a
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diff --git a/README.md b/README.md
@@ -95,6 +95,7 @@ import (
 	"log"
 
 	"github.com/xhit/go-simple-mail/v2"
+	"github.com/toorop/go-dkim"
 )
 
 const htmlBody = `<html>
@@ -109,6 +110,34 @@ const htmlBody = `<html>
 	</body>
 </html>`
 
+const privateKey = `-----BEGIN RSA PRIVATE KEY-----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+-----END RSA PRIVATE KEY-----`
+
 func main() {
 	server := mail.NewSMTPClient()
 
@@ -151,7 +180,8 @@ func main() {
 	email.SetFrom("From Example <[email protected]>").
 		AddTo("[email protected]").
 		AddCc("[email protected]").
-		SetSubject("New Go Email")
+		SetSubject("New Go Email").
+		SetListUnsubscribe("<mailto:[email protected]?subject=https://example.com/unsubscribe>").
 
 	email.SetBody(mail.TextHTML, htmlBody)
 
@@ -163,6 +193,21 @@ func main() {
 	// add inline
 	email.Attach(&mail.File{FilePath: "/path/to/image.png", Name:"Gopher.png", Inline: true})
 
+	// you can add dkim signature to the email. 
+	// to add dkim, you need a private key already created one.
+	if privateKey != "" {
+		options := dkim.NewSigOptions()
+		options.PrivateKey = []byte(privateKey)
+		options.Domain = "example.com"
+		options.Selector = "default"
+		options.SignatureExpireIn = 3600
+		options.Headers = []string{"from", "date", "mime-version", "received", "received"}
+		options.AddSignatureTimestamp = true
+		options.Canonicalization = "relaxed/relaxed"
+
+		email.SetDkim(options)
+	}
+
 	// always check error after send
 	if email.Error != nil{
 		log.Fatal(email.Error)

diff --git a/email.go b/email.go
@@ -10,6 +10,8 @@ import (
 	"net/textproto"
 	"strconv"
 	"time"
+
+	"github.com/toorop/go-dkim"
 )
 
 // Email represents an email message.
@@ -27,6 +29,7 @@ type Email struct {
 	Encoding    encoding
 	Error       error
 	SMTPServer  *smtpClient
+	DkimMsg     string
 }
 
 /*
@@ -420,6 +423,36 @@ func (email *Email) SetSubject(subject string) *Email {
 	return email
 }
 
+// SetListUnsubscribe sets the Unsubscribe address.
+func (email *Email) SetListUnsubscribe(address string) *Email {
+	if email.Error != nil {
+		return email
+	}
+
+	email.AddHeader("List-Unsubscribe", address)
+
+	return email
+}
+
+// SetDkim adds DomainKey signature to the email message (header+body)
+func (email *Email) SetDkim(options dkim.SigOptions) *Email {
+	if email.Error != nil {
+		return email
+	}
+
+	msg := []byte(email.GetMessage())
+	err := dkim.Sign(&msg, options)
+
+	if err != nil {
+		email.Error = errors.New("Mail Error: cannot dkim sign message due: %s" + err.Error())
+		return email
+	}
+
+	email.DkimMsg = string(msg)
+
+	return email
+}
+
 // SetBody sets the body of the email message.
 func (email *Email) SetBody(contentType contentType, body string) *Email {
 	if email.Error != nil {
@@ -488,6 +521,8 @@ func (email *Email) AddHeader(header string, values ...string) *Email {
 			return email
 		}
 		email.SetDate(values[0])
+	case "List-Unsubscribe":
+		fallthrough
 	default:
 		email.headers[header] = values
 	}
@@ -636,7 +671,12 @@ func (email *Email) SendEnvelopeFrom(from string, client *SMTPClient) error {
 		return errors.New("Mail Error: No recipient specified")
 	}
 
-	msg := email.GetMessage()
+	var msg string
+	if email.DkimMsg != "" {
+		msg = email.DkimMsg
+	} else {
+		msg = email.GetMessage()
+	}
 
 	return send(from, email.recipients, msg, client)
 }

diff --git a/go.mod b/go.mod
@@ -1,3 +1,6 @@
 module github.com/xhit/go-simple-mail/v2
+require (
+	github.com/toorop/go-dkim v0.0.0-20201103131630-e1cd1a0a5208
+)
 
 go 1.13
diff --git a/go.sum b/go.sum
@@ -0,0 +1,4 @@
+github.com/toorop/go-dkim v0.0.0-20201103131630-e1cd1a0a5208 h1:PM5hJF7HVfNWmCjMdEfbuOBNXSVF2cMFGgQTPdKCbwM=
+github.com/toorop/go-dkim v0.0.0-20201103131630-e1cd1a0a5208/go.mod h1:BzWtXXrXzZUvMacR0oF/fbDDgUPO8L36tDMmRAf14ns=
+github.com/xhit/go-simple-mail v2.2.2+incompatible h1:Hm2VGfLqiQJ/NnC8SYsrPOPyVYIlvP2kmnotP4RIV74=
+github.com/xhit/go-simple-mail v2.2.2+incompatible/go.mod h1:I8Ctg6vIJZ+Sv7k/22M6oeu/tbFumDY0uxBuuLbtU7Y=