func getSubject(msg *mail.Message) (string, error) {
var dec mime.WordDecoder
ret, err := dec.DecodeHeader(msg.Header.Get("Subject"))
if err != nil {
return "", err
}
return ret, nil
}
// DecodeHeader (per RFC 2047) using Golang's mime.WordDecoder
func DecodeHeader(input string) string {
if !strings.Contains(input, "=?") {
// Don't scan if there is nothing to do here
return input
}
dec := new(mime.WordDecoder)
dec.CharsetReader = NewCharsetReader
header, err := dec.DecodeHeader(input)
if err != nil {
return input
}
return header
}
// NonASCII Decode non ASCII header string RFC 1342
func NonASCII(encoded string) string {
regexRFC1342, _ := regexp.Compile(`=\?.*?\?=`)
dec := new(mime.WordDecoder)
dec.CharsetReader = charset.NewReader
result := regexRFC1342.ReplaceAllStringFunc(encoded, func(encoded string) string {
decoded, err := dec.Decode(encoded)
if err != nil {
log.Println("Error decode NonASCII", encoded, err)
return encoded
}
return decoded
})
return result
}
func parseAndDecodeHeader(rawMimeHeader textproto.MIMEHeader, target string,
mHeader PMIMEHeader) string {
if targetArray, ok := rawMimeHeader[target]; !ok && len(targetArray) == 0 {
return ""
} else {
var (
encodedValue string = strings.TrimPrefix(targetArray[0], " ")
decoded string
dec *mime.WordDecoder = new(mime.WordDecoder)
err error
)
if decoded, err = dec.DecodeHeader(encodedValue); err != nil {
fmt.Printf("[watney] WARNING: Couldn't decode string: \n\t%s\n\t%s\n", encodedValue,
err.Error())
return encodedValue
}
return decoded
}
}
func ExampleWordDecoder_Decode() {
dec := new(mime.WordDecoder)
header, err := dec.Decode("=?utf-8?q?=C2=A1Hola,_se=C3=B1or!?=")
if err != nil {
panic(err)
}
fmt.Println(header)
dec.CharsetReader = func(charset string, input io.Reader) (io.Reader, error) {
switch charset {
case "x-case":
// Fake character set for example.
// Real use would integrate with packages such
// as code.google.com/p/go-charset
content, err := ioutil.ReadAll(input)
if err != nil {
return nil, err
}
return bytes.NewReader(bytes.ToUpper(content)), nil
default:
return nil, fmt.Errorf("unhandled charset %q", charset)
}
}
header, err = dec.Decode("=?x-case?q?hello!?=")
if err != nil {
panic(err)
}
fmt.Println(header)
// Output:
// ¡Hola, señor!
// HELLO!
}
func WordDecoder() *mime.WordDecoder {
decoder := new(mime.WordDecoder)
decoder.CharsetReader = CharsetReader
return decoder
}
// Parse parses a MIME encoded message.
func Parse(r io.Reader) (
header *Header,
subject string,
message string,
attachments []*Attachment,
err error,
) {
var h Header
// read message
msg, err := mail.ReadMessage(r)
if err != nil {
return nil, "", "", nil, log.Error(err)
}
// parse 'From'
h.From = msg.Header.Get("From")
if h.From == "" {
return nil, "", "", nil, log.Error("mime: 'From' not defined")
}
// parse 'To'
h.To = msg.Header.Get("To")
if h.To == "" {
return nil, "", "", nil, log.Error("mime: 'To' not defined")
}
// parse 'Cc'
addressList, err := msg.Header.AddressList("Cc")
if err != nil && err != mail.ErrHeaderNotPresent {
return nil, "", "", nil, log.Error(err)
}
if err != mail.ErrHeaderNotPresent {
for _, address := range addressList {
h.Cc = append(h.Cc, address.Address)
}
}
// parse subject
subj := msg.Header.Get("Subject")
if subj == "" {
return nil, "", "", nil, log.Error("mime: 'Subject' not defined")
}
dec := new(mime.WordDecoder)
subject, err = dec.DecodeHeader(subj)
if err != nil {
return nil, "", "", nil, log.Error(err)
}
// parse 'Message-ID'
h.MessageID = msg.Header.Get("Message-ID")
if h.MessageID == "" {
return nil, "", "", nil, log.Error("mime: 'Message-ID' not defined")
}
// parse 'In-Reply-To'
h.InReplyTo = msg.Header.Get("In-Reply-To")
// parse 'MIME-Version'
if msg.Header.Get("MIME-Version") != "1.0" {
return nil, "", "", nil, log.Error("mime: wrong 'MIME-Version' header")
}
// parse 'Content-Type'
mediaType, params, err := mime.ParseMediaType(msg.Header.Get("Content-Type"))
if err != nil {
return nil, "", "", nil, log.Error(err)
} else if mediaType != "multipart/mixed" {
return nil, "", "", nil, log.Error("mime: wrong 'Content-Type' header ")
}
// read first MIME part (message)
mr := multipart.NewReader(msg.Body, params["boundary"])
p, err := mr.NextPart()
if err != nil {
return nil, "", "", nil, log.Error(err)
}
// check 'Content-Type'
if p.Header.Get("Content-Type") != "text/plain" {
return nil, "", "", nil,
log.Error("mime: expected 'text/plain' Content-Type")
}
// check 'Content-Transfer-Encoding'
if p.Header.Get("Content-Transfer-Encoding") != "base64" {
return nil, "", "", nil,
log.Error("mime: expected 'base64' Content-Transfer-Encoding")
}
// read message
enc, err := ioutil.ReadAll(p)
if err != nil {
return nil, "", "", nil, log.Error(err)
}
content, err := base64.Decode(string(enc))
if err != nil {
return nil, "", "", nil, log.Error(err)
}
message = string(content)
// read optional additional MIME parts (attachments)
for {
p, err := mr.NextPart()
if err == io.EOF {
break
}
// parse header
contentType := p.Header.Get("Content-Type")
if contentType == "" {
return nil, "", "", nil,
log.Error("mime: Content-Type undefined for attachment")
}
var filename string
var inline bool
for _, disposition := range p.Header["Content-Disposition"] {
mediaType, params, err := mime.ParseMediaType(disposition)
if err != nil {
return nil, "", "", nil, log.Error(err)
}
switch mediaType {
case "attachment":
filename = params["filename"]
case "inline":
inline = true
default:
return nil, "", "", nil,
log.Errorf("mime: unknown Content-Disposition in attachment: %s",
mediaType)
}
}
if filename == "" {
log.Error("mime: filename undefined for attachment")
}
// parse body
if err != nil {
return nil, "", "", nil, log.Error(err)
}
enc, err := ioutil.ReadAll(p)
if err != nil {
return nil, "", "", nil, log.Error(err)
}
content, err := base64.Decode(string(enc))
if err != nil {
return nil, "", "", nil, log.Error(err)
}
// reconstruct attachment
attachment := &Attachment{
Filename: filename,
Reader: bytes.NewBuffer(content),
ContentType: contentType,
Inline: inline,
}
attachments = append(attachments, attachment)
}
header = &h
return
}
