vxml.cxx

pwlib源码库

///////////////////////////////////////////////////////////////

BOOL PVXMLPlayableURL::Open(PVXMLChannel & chan, const PString & _url, PINDEX _delay, PINDEX _repeat, BOOL autoDelete)
{ 
  url = arg = _url; 
  return PVXMLPlayable::Open(chan, _delay, _repeat, autoDelete); 
}

void PVXMLPlayableURL::Play(PVXMLChannel & outgoingChannel)
{
  // open the resource
  PHTTPClient * client = new PHTTPClient;
  PMIMEInfo outMIME, replyMIME;
  int code = client->GetDocument(url, outMIME, replyMIME, FALSE);
  if ((code != 200) || (replyMIME(PHTTP::TransferEncodingTag) *= PHTTP::ChunkedTag))
    delete client;
  else {
    outgoingChannel.SetReadChannel(client, TRUE);
  }
}

PFactory<PVXMLPlayable>::Worker<PVXMLPlayableURL> vxmlPlayableURLFactory("URL");

///////////////////////////////////////////////////////////////

BOOL PVXMLRecordableFilename::Open(const PString & _arg)
{ 
  fn = _arg;
  consecutiveSilence = 0;
  return TRUE;
}

void PVXMLRecordableFilename::Record(PVXMLChannel & outgoingChannel)
{
  PChannel * chan = NULL;

  // check the file extension and open a .wav or a raw (.sw or .g723) file
  if ((fn.Right(4)).ToLower() == ".wav")
    chan = outgoingChannel.CreateWAVFile(fn, TRUE);
  else {
    PFile * fileChan = new PFile(fn);
    if (fileChan->Open(PFile::WriteOnly))
      chan = fileChan;
    else {
      delete fileChan;
    }
  }

  if (chan == NULL)
    PTRACE(3, "PVXML\tCannot open file \"" << fn << "\"");
  else {
    PTRACE(3, "PVXML\tRecording to file \"" << fn << "\"");
    outgoingChannel.SetWriteChannel(chan, TRUE);
  }

  recordStart  = PTime();
  silenceStart = PTime();
  consecutiveSilence = 0;
}

BOOL PVXMLRecordableFilename::OnFrame(BOOL isSilence)
{
  if (!isSilence) {
    silenceStart = PTime();
    consecutiveSilence = 0;
  } else {
    consecutiveSilence++;
    if ( ((consecutiveSilence % 20) == 0) &&
        (
          ((finalSilence > 0) && ((PTime() - silenceStart).GetMilliSeconds() >= finalSilence)) || 
          ((maxDuration  > 0) && ((PTime() - recordStart).GetMilliSeconds() >= maxDuration))
          )
       )
      return TRUE;
  }

  return FALSE;
}

///////////////////////////////////////////////////////////////

PVXMLCache::PVXMLCache(const PDirectory & _directory)
  : directory(_directory)
{
  if (!directory.Exists())
    directory.Create();
}

static PString MD5AsHex(const PString & str)
{
  PMessageDigest::Result digest;
  PMessageDigest5::Encode(str, digest);

  PString hexStr;
  const BYTE * data = digest.GetPointer();
  for (PINDEX i = 0; i < digest.GetSize(); ++i)
    hexStr.sprintf("%02x", (unsigned)data[i]);
  return hexStr;
}


PFilePath PVXMLCache::CreateFilename(const PString & prefix, const PString & key, const PString & fileType)
{
  PString md5   = MD5AsHex(key);
  PString md5_2 = MD5AsHex(key);

  return directory + ((prefix + "_") + md5 + fileType);
}

BOOL PVXMLCache::Get(const PString & prefix,
                     const PString & key, 
                     const PString & fileType, 
                           PString & contentType, 
                         PFilePath & dataFn)
{
  PWaitAndSignal m(*this);

  dataFn = CreateFilename(prefix, key, "." + fileType);
  PFilePath typeFn = CreateFilename(prefix, key, "_type.txt");
  if (!PFile::Exists(dataFn) || !PFile::Exists(typeFn)) {
    PTRACE(4, "Key \"" << key << "\" not found in cache");
    return FALSE;
  }

  PTextFile typeFile(typeFn, PFile::ReadOnly);
  if (!typeFile.IsOpen()) {
    PTRACE(4, "Cannot find type for cached key " << key << " in cache");
    PFile::Remove(dataFn);
    return FALSE;
  }

  typeFile.ReadLine(contentType);
  contentType.Trim();
  if (contentType.IsEmpty())
    contentType = GetContentType(dataFn);

  return TRUE;
}

void PVXMLCache::Put(const PString & prefix,
                     const PString & key, 
                     const PString & fileType, 
                     const PString & contentType,       
                   const PFilePath & fn, 
                         PFilePath & dataFn)
{
  PWaitAndSignal m(*this);

  // create the filename for the cache files
  dataFn = CreateFilename(prefix, key, "." + fileType);
  PFilePath typeFn = CreateFilename(prefix, key, "_type.txt");

  // write the content type file
  PTextFile typeFile(typeFn, PFile::WriteOnly);
  if (contentType.IsEmpty())
    typeFile.WriteLine(GetContentType(fn));
  else
    typeFile.WriteLine(contentType);

  // rename the file to the correct name
  PFile::Rename(fn, dataFn.GetFileName(), TRUE);
}

PVXMLCache & PVXMLCache::GetResourceCache()
{
  static PVXMLCache cache(PDirectory() + "cache");
  return cache;
}


PFilePath PVXMLCache::GetRandomFilename(const PString & prefix, const PString & fileType)
{
  PFilePath fn;

  // create a random temporary filename
  PRandom r;
  for (;;) {
    fn = directory + psprintf("%s_%i.%s", (const char *)prefix, r.Generate() % 1000000, (const char *)fileType);
    if (!PFile::Exists(fn))
      break;
  }

  return fn;
}

//////////////////////////////////////////////////////////

PVXMLSession::PVXMLSession(PTextToSpeech * _tts, BOOL autoDelete)
{
  vxmlThread       = NULL;
  vxmlChannel      = NULL;
  finishWhenEmpty  = TRUE;
  textToSpeech     = NULL;

  SetTextToSpeech(_tts, autoDelete);

  Initialise();
}

void PVXMLSession::Initialise()
{
  recording        = FALSE;
  allowFinish      = FALSE;
  listening        = FALSE;
  activeGrammar    = NULL;
  listening        = FALSE;
  forceEnd         = FALSE;
  currentForm      = NULL;
  currentNode      = NULL;
}

PVXMLSession::~PVXMLSession()
{
  Close();

  if ((textToSpeech != NULL) && autoDeleteTextToSpeech)
    delete textToSpeech;
}

PTextToSpeech * PVXMLSession::SetTextToSpeech(PTextToSpeech * _tts, BOOL autoDelete)
{
  PWaitAndSignal m(sessionMutex);

  if (autoDeleteTextToSpeech && (textToSpeech != NULL))
    delete textToSpeech;

  autoDeleteTextToSpeech = autoDelete;
  textToSpeech = _tts;
  return textToSpeech;
}

PTextToSpeech * PVXMLSession::SetTextToSpeech(const PString & ttsName)
{
  PWaitAndSignal m(sessionMutex);

  if (autoDeleteTextToSpeech && (textToSpeech != NULL))
    delete textToSpeech;

  autoDeleteTextToSpeech = TRUE;
  textToSpeech = PFactory<PTextToSpeech>::CreateInstance(ttsName);
  return textToSpeech;
}

BOOL PVXMLSession::Load(const PString & source)
{
  // Lets try and guess what was passed, if file exists then is file
  PFilePath file = source;
  if (PFile::Exists(file))
    return LoadFile(file);

  // see if looks like URL
  PINDEX pos = source.Find(':');
  if (pos != P_MAX_INDEX) {
    PString scheme = source.Left(pos);
    if ((scheme *= "http") || (scheme *= "https") || (scheme *= "file"))
      return LoadURL(source);
  }

  // See if is actual VXML
  if (PCaselessString(source).Find("<vxml") != P_MAX_INDEX)
    return LoadVXML(source);

  return FALSE;
}


BOOL PVXMLSession::LoadFile(const PFilePath & filename)
{
  // create a file URL from the filename
  return LoadURL(filename);
}


BOOL PVXMLSession::LoadURL(const PURL & url)
{
  // retreive the document (may be a HTTP get)
  PFilePath fn;
  PString contentType;
  if (!RetreiveResource(url, contentType, fn, FALSE)) {
    PTRACE(1, "PVXML\tCannot load document " << url);
    return FALSE;
  }

  PTextFile file(fn, PFile::ReadOnly);
  if (!file.IsOpen()) {
    PTRACE(1, "PVXML\tCannot read data from " << fn);
    return FALSE;
  }

  off_t len = file.GetLength();
  PString text;
  file.Read(text.GetPointer(len+1), len);
  len = file.GetLastReadCount();
  text.SetSize(len+1);
  text[(PINDEX)len] = '\0';

  if (!LoadVXML(text)) {
    PTRACE(1, "PVXML\tCannot load VXML in " << url);
    return FALSE;
  }

  rootURL = url;
  return TRUE;
}

BOOL PVXMLSession::LoadVXML(const PString & xmlText)
{
  PWaitAndSignal m(sessionMutex);

  allowFinish = loaded = FALSE;
  rootURL = PString::Empty();

  // parse the XML
  xmlFile.RemoveAll();
  if (!xmlFile.Load(xmlText)) {
    PTRACE(1, "PVXML\tCannot parse root document: " << GetXMLError());
    return FALSE;
  }  

  PXMLElement * root = xmlFile.GetRootElement();
  if (root == NULL)
    return FALSE;

  // reset interpeter state
  Initialise();

  // find the first form
  if ((currentForm = FindForm(PString::Empty())) == NULL)
    return FALSE;

  // start processing with this <form> element
  currentNode = currentForm;

  loaded = TRUE;
  return TRUE;
}

PURL PVXMLSession::NormaliseResourceName(const PString & src)
{
  // if resource name has a scheme, then use as is
  PINDEX pos = src.Find(':');
  if ((pos != P_MAX_INDEX) && (pos < 5))
    return src;

  if (rootURL.IsEmpty())
    return "file:" + src;

  // else use scheme and path from root document
  PURL url = rootURL;
  PStringArray path = url.GetPath();
  PString pathStr;
  if (path.GetSize() > 0) {
    pathStr += path[0];
    PINDEX i;
    for (i = 1; i < path.GetSize()-1; i++)
      pathStr += "/" + path[i];
    pathStr += "/" + src;
    url.SetPathStr(pathStr);
  }

  return url;
}


BOOL PVXMLSession::RetreiveResource(const PURL & url, 
                                       PString & contentType, 
                                     PFilePath & dataFn,
                                            BOOL useCache)
{
  BOOL stat = FALSE;

  // files on the local file system get loaded locally
  if (url.GetScheme() *= "file") {
    dataFn = url.AsFilePath();
    if (contentType.IsEmpty())
      contentType = GetContentType(dataFn);
    stat = TRUE;
  }

  // do a HTTP get when appropriate
  else if ((url.GetScheme() *= "http") || (url.GetScheme() *= "https")) {

    PFilePath fn;
    PString fileType = url.AsFilePath().GetType();

    BOOL inCache = FALSE;
    if (useCache)
      inCache = PVXMLCache::GetResourceCache().Get("url", url.AsString(), fileType, contentType, dataFn);

    if (!inCache) {

      // get a random filename
      fn = PVXMLCache::GetResourceCache().GetRandomFilename("url", fileType);

      // get the resource header information
      PHTTPClient client;
      PMIMEInfo outMIME, replyMIME;
      if (!client.GetDocument(url, outMIME, replyMIME)) {
        PTRACE(2, "PVXML\tCannot load resource " << url);
        stat =FALSE;
      } 
      
      else {

        // Get the body of the response in a PBYTEArray (might be binary data)
        PBYTEArray incomingData;
        client.ReadContentBody(replyMIME, incomingData);
        contentType = replyMIME(PHTTPClient::ContentTypeTag);

        // write the data in the file
        PFile cacheFile(fn, PFile::WriteOnly);
        cacheFile.Write(incomingData.GetPointer(), incomingData.GetSize() );

        // if we have a cache and we are using it, then save the data
        if (useCache) 
          PVXMLCache::GetResourceCache().Put("url", url.AsString(), fileType, contentType, fn, dataFn);

        // data is loaded
        stat = TRUE;
      }
    }
  }

  // files on the local file system get loaded locally
  else if (url.GetScheme() *= "file") {
    dataFn = url.AsFilePath();
    stat = TRUE;
  }

  // unknown schemes give an error
  else 
    stat = FALSE;

  return stat;
}


PXMLElement * PVXMLSession::FindForm(const PString & id)
{
  // NOTE: should have some flag to know if it is loaded
  PXMLElement * root = xmlFile.GetRootElement();
  if (root == NULL)
    return NULL;
  
  // Only handle search of top level nodes for <form> element
  PINDEX i;
  for (i = 0; i < root->GetSize(); i++) {
    PXMLObject * xmlObject = root->GetElement(i); 
    if (xmlObject->IsElement()) {
      PXMLElement * xmlElement = (PXMLElement*)xmlObject;
      if (
          (xmlElement->GetName() *= "form") && 
          (id.IsEmpty() || (xmlElement->GetAttribute("id") *= id))
         )
        return xmlElement;
    }
  }
  return NULL;
}


BOOL PVXMLSession::Open(BOOL isPCM)
{
  if (isPCM)
    return Open(VXML_PCM16);
  else
    return Open(VXML_G7231);
}

BOOL PVXMLSession::Open(const PString & _mediaFormat)
{
  mediaFormat = _mediaFormat;

  PVXMLChannel * chan = PFactory<PVXMLChannel>::CreateInstance(mediaFormat);
  if (chan == NULL) {
    PTRACE(1, "VXML\tCannot create VXML channel with format " << mediaFormat);
    return FALSE;
  }

  // set the underlying channel
  if (!PIndirectChannel::Open(chan, chan))
    return FALSE;

  // start the VXML session in another thread