Merge pull request #398 from janhq/397-grammar-file-not-found-llamacppcc201

bug: correct way of handle grammar file

Author: tikikun

controllers/llamaCPP.cc

@@ -186,15 +186,19 @@ void llamaCPP::chatCompletion(
         (*jsonBody).get("frequency_penalty", 0).asFloat();
     data["presence_penalty"] = (*jsonBody).get("presence_penalty", 0).asFloat();
     const Json::Value &messages = (*jsonBody)["messages"];
-    std::string grammar_file = (*jsonBody).get("grammar_file", "").asString();
-    std::ifstream file(grammar_file);
-    if (!file) {
-      LOG_ERROR << "Grammar file not found";
-    } else {
-      std::stringstream grammarBuf;
-      grammarBuf << file.rdbuf();
-      data["grammar"] = grammarBuf.str();
-    }
+
+    if (!(*jsonBody)["grammar_file"].isNull()) {
+      std::string grammar_file = (*jsonBody)["grammar_file"].asString();
+      std::ifstream file(grammar_file);
+      if (!file) {
+        LOG_ERROR << "Grammar file not found";
+      } else {
+        std::stringstream grammarBuf;
+        grammarBuf << file.rdbuf();
+        data["grammar"] = grammarBuf.str();
+      }
+    };
+
     if (!llama.multimodal) {
 
       for (const auto &message : messages) {