Allow more online models to load tokens file from the memory (#1352)

Co-authored-by: xiao <shawl336@6163.com>

sherpa-onnx/c-api/c-api.cc

@@ -667,6 +667,12 @@ SherpaOnnxKeywordSpotter *SherpaOnnxCreateKeywordSpotter(
 
   spotter_config.model_config.tokens =
       SHERPA_ONNX_OR(config->model_config.tokens, "");
+  if (config->model_config.tokens_buf &&
+      config->model_config.tokens_buf_size > 0) {
+    spotter_config.model_config.tokens_buf = std::string(
+        config->model_config.tokens_buf, config->model_config.tokens_buf_size);
+  }
+
   spotter_config.model_config.num_threads =
       SHERPA_ONNX_OR(config->model_config.num_threads, 1);
   spotter_config.model_config.provider_config.provider =
@@ -691,6 +697,10 @@ SherpaOnnxKeywordSpotter *SherpaOnnxCreateKeywordSpotter(
       SHERPA_ONNX_OR(config->keywords_threshold, 0.25);
 
   spotter_config.keywords_file = SHERPA_ONNX_OR(config->keywords_file, "");
+  if (config->keywords_buf && config->keywords_buf_size > 0) {
+    spotter_config.keywords_buf =
+        std::string(config->keywords_buf, config->keywords_buf_size);
+  }
 
   if (config->model_config.debug) {
     SHERPA_ONNX_LOGE("%s\n", spotter_config.ToString().c_str());

sherpa-onnx/c-api/c-api.h

@@ -88,8 +88,8 @@ SHERPA_ONNX_API typedef struct SherpaOnnxOnlineModelConfig {
   //  - cjkchar+bpe
   const char *modeling_unit;
   const char *bpe_vocab;
-  /// if non-null, loading the tokens from the buffered string directly in
-  /// prioriy
+  /// if non-null, loading the tokens from the buffer instead of from the
+  /// "tokens" file
   const char *tokens_buf;
   /// byte size excluding the trailing '\0'
   int32_t tokens_buf_size;
@@ -637,6 +637,11 @@ SHERPA_ONNX_API typedef struct SherpaOnnxKeywordSpotterConfig {
   float keywords_score;
   float keywords_threshold;
   const char *keywords_file;
+  /// if non-null, loading the keywords from the buffer instead of from the
+  /// keywords_file
+  const char *keywords_buf;
+  /// byte size excluding the trailing '\0'
+  int32_t keywords_buf_size;
 } SherpaOnnxKeywordSpotterConfig;
 
 SHERPA_ONNX_API typedef struct SherpaOnnxKeywordSpotter

sherpa-onnx/csrc/keyword-spotter-transducer-impl.h

@@ -66,15 +66,25 @@ class KeywordSpotterTransducerImpl : public KeywordSpotterImpl {
  public:
   explicit KeywordSpotterTransducerImpl(const KeywordSpotterConfig &config)
       : config_(config),
-        model_(OnlineTransducerModel::Create(config.model_config)),
-        sym_(config.model_config.tokens) {
+        model_(OnlineTransducerModel::Create(config.model_config)) {
+    if (!config.model_config.tokens_buf.empty()) {
+      sym_ = SymbolTable(config.model_config.tokens_buf, false);
+    } else {
+      /// assuming tokens_buf and tokens are guaranteed not being both empty
+      sym_ = SymbolTable(config.model_config.tokens, true);
+    }
+
     if (sym_.Contains("<unk>")) {
       unk_id_ = sym_["<unk>"];
     }
 
     model_->SetFeatureDim(config.feat_config.feature_dim);
 
-    InitKeywords();
+    if (config.keywords_buf.empty()) {
+      InitKeywords();
+    } else {
+      InitKeywordsFromBufStr();
+    }
 
     decoder_ = std::make_unique<TransducerKeywordDecoder>(
         model_.get(), config_.max_active_paths, config_.num_trailing_blanks,
@@ -305,6 +315,12 @@ class KeywordSpotterTransducerImpl : public KeywordSpotterImpl {
   }
 #endif
 
+  void InitKeywordsFromBufStr() {
+    // keywords_buf's content is supposed to be same as the keywords_file's
+    std::istringstream is(config_.keywords_buf);
+    InitKeywords(is);
+  }
+
   void InitOnlineStream(OnlineStream *stream) const {
     auto r = decoder_->GetEmptyResult();
     SHERPA_ONNX_CHECK_EQ(r.hyps.Size(), 1);

sherpa-onnx/csrc/keyword-spotter.cc

@@ -89,8 +89,17 @@ void KeywordSpotterConfig::Register(ParseOptions *po) {
 }
 
 bool KeywordSpotterConfig::Validate() const {
-  if (keywords_file.empty()) {
-    SHERPA_ONNX_LOGE("Please provide --keywords-file.");
+  if (!keywords_file.empty() && !keywords_buf.empty()) {
+    SHERPA_ONNX_LOGE(
+        "you can not provide a keywords_buf and a keywords file: '%s', "
+        "at the same time, which is confusing",
+        keywords_file.c_str());
+    return false;
+  }
+
+  if (keywords_file.empty() && keywords_buf.empty()) {
+    SHERPA_ONNX_LOGE(
+        "Please provide either a keywords-file or the keywords-buf");
     return false;
   }
 
@@ -99,7 +108,7 @@ bool KeywordSpotterConfig::Validate() const {
   // keywords file will be packaged into the sherpa-onnx-wasm-kws-main.data file
   // Solution: take keyword_file variable is directly
   // parsed as a string of keywords
-  if (!std::ifstream(keywords_file.c_str()).good()) {
+  if (keywords_buf.empty() && !std::ifstream(keywords_file.c_str()).good()) {
     SHERPA_ONNX_LOGE("Keywords file '%s' does not exist.",
                      keywords_file.c_str());
     return false;

sherpa-onnx/csrc/keyword-spotter.h

@@ -69,6 +69,11 @@ struct KeywordSpotterConfig {
 
   std::string keywords_file;
 
+  /// if keywords_buf is non-empty,
+  /// the keywords will be loaded from the buffer instead of from the
+  /// "keywrods_file"
+  std::string keywords_buf;
+
   KeywordSpotterConfig() = default;
 
   KeywordSpotterConfig(const FeatureExtractorConfig &feat_config,

sherpa-onnx/csrc/online-model-config.h

@@ -46,8 +46,8 @@ struct OnlineModelConfig {
   std::string bpe_vocab;
 
   /// if tokens_buf is non-empty,
-  /// the tokens will be loaded from the buffered string instead of from the
-  /// ${tokens} file
+  /// the tokens will be loaded from the buffer instead of from the
+  /// "tokens" file
   std::string tokens_buf;
 
   OnlineModelConfig() = default;

sherpa-onnx/csrc/online-recognizer-ctc-impl.h

@@ -71,8 +71,14 @@ class OnlineRecognizerCtcImpl : public OnlineRecognizerImpl {
       : OnlineRecognizerImpl(config),
         config_(config),
         model_(OnlineCtcModel::Create(config.model_config)),
-        sym_(config.model_config.tokens),
         endpoint_(config_.endpoint_config) {
+    if (!config.model_config.tokens_buf.empty()) {
+      sym_ = SymbolTable(config.model_config.tokens_buf, false);
+    } else {
+      /// assuming tokens_buf and tokens are guaranteed not being both empty
+      sym_ = SymbolTable(config.model_config.tokens, true);
+    }
+
     if (!config.model_config.wenet_ctc.model.empty()) {
       // WeNet CTC models assume input samples are in the range
       // [-32768, 32767], so we set normalize_samples to false

sherpa-onnx/csrc/online-recognizer-paraformer-impl.h

@@ -99,8 +99,14 @@ class OnlineRecognizerParaformerImpl : public OnlineRecognizerImpl {
       : OnlineRecognizerImpl(config),
         config_(config),
         model_(config.model_config),
-        sym_(config.model_config.tokens),
         endpoint_(config_.endpoint_config) {
+    if (!config.model_config.tokens_buf.empty()) {
+      sym_ = SymbolTable(config.model_config.tokens_buf, false);
+    } else {
+      /// assuming tokens_buf and tokens are guaranteed not being both empty
+      sym_ = SymbolTable(config.model_config.tokens, true);
+    }
+
     if (config.decoding_method != "greedy_search") {
       SHERPA_ONNX_LOGE(
           "Unsupported decoding method: %s. Support only greedy_search at "

sherpa-onnx/csrc/online-recognizer.h

@@ -107,8 +107,8 @@ struct OnlineRecognizerConfig {
   std::string rule_fars;
 
   /// used only for modified_beam_search, if hotwords_buf is non-empty,
-  /// the hotwords will be loaded from the buffered string instead of from
-  /// ${hotwords_file}
+  /// the hotwords will be loaded from the buffered string instead of from the
+  /// "hotwords_file"
   std::string hotwords_buf;
 
   OnlineRecognizerConfig() = default;