// getMimeFromMagic accepts a sample and counter and then tries to determin the
// mime type of the file. If a panic occures in an external library the function
// will recover and try to get the mime type up to three times before returning
// "N/A" as mime type.
func getMimeFromMagic(fileBytes []byte, try int) (mimeType string, err error) {
defer func() {
magicmime.Close()
mimeLock.Unlock()
if err := recover(); err != nil {
warning.Println("magicMime paniced")
time.Sleep(time.Second)
mimeType, err = getMimeFromMagic(fileBytes, try+1)
}
}()
// if we tried to get the mimeType 3 times but paniced we'll return a
// static string
if try >= 3 {
err = nil
mimeType = "N/A"
return
}
mimeLock.Lock()
err = magicmime.Open(magicmime.MAGIC_ERROR)
if err != nil {
err = errors.New("ExtendedMime is activated but libmagic is not installed!")
return
}
mimeType, err = magicmime.TypeByBuffer(fileBytes)
return
}
// GetMimetype gets the mimetype of a data []byte
func GetMimetype(data []byte) (string, error) {
if err := magicmime.Open(magicmime.MAGIC_NO_CHECK_COMPRESS); err != nil {
return "", err
}
defer magicmime.Close()
mimetype, err := magicmime.TypeByBuffer(data)
if err != nil {
return "", err
}
return mimetype, nil
}