fix: improve error message when load model failed

engine/cli/commands/model_start_cmd.cc

@@ -6,6 +6,7 @@
 #include "run_cmd.h"
 #include "server_start_cmd.h"
 #include "utils/cli_selection_utils.h"
+#include "utils/json_helper.h"
 #include "utils/logging_utils.h"
 
 namespace commands {
@@ -14,7 +15,7 @@ bool ModelStartCmd::Exec(const std::string& host, int port,
   std::optional<std::string> model_id =
       SelectLocalModel(model_service_, model_handle);
 
-  if(!model_id.has_value()) {
+  if (!model_id.has_value()) {
     return false;
   }
 
@@ -41,7 +42,8 @@ bool ModelStartCmd::Exec(const std::string& host, int port,
                                << *model_id << "` for interactive chat shell");
       return true;
     } else {
-      CTL_ERR("Model failed to load with status code: " << res->status);
+      auto root = json_helper::ParseJsonString(res->body);
+      CLI_LOG(root["message"].asString());
       return false;
     }
   } else {

engine/services/inference_service.cc

@@ -140,9 +140,9 @@ InferResult InferenceService::LoadModel(
       if (IsEngineLoaded(kLlamaRepo) && ne == kTrtLlmRepo) {
         // Remove llamacpp dll directory
         if (!RemoveDllDirectory(engines_[kLlamaRepo].cookie)) {
-          LOG_INFO << "Could not remove dll directory: " << kLlamaRepo;
+          LOG_WARN << "Could not remove dll directory: " << kLlamaRepo;
         } else {
-          LOG_WARN << "Removed dll directory: " << kLlamaRepo;
+          LOG_INFO << "Removed dll directory: " << kLlamaRepo;
         }
 
         add_dll(ne, abs_path);
@@ -158,7 +158,7 @@ InferResult InferenceService::LoadModel(
       LOG_ERROR << "Could not load engine: " << e.what();
       engines_.erase(ne);
 
-      r["message"] = "Could not load engine " + ne;
+      r["message"] = "Could not load engine " + ne + ": " + e.what();
       stt["status_code"] = k500InternalServerError;
       return std::make_pair(stt, r);
     }

engine/services/model_service.cc

@@ -14,6 +14,7 @@
 #include "utils/logging_utils.h"
 #include "utils/result.hpp"
 #include "utils/string_utils.h"
+#include "utils/json_helper.h"
 
 namespace {
 void ParseGguf(const DownloadItem& ggufDownloadItem,
@@ -622,9 +623,9 @@ cpp::result<bool, std::string> ModelService::StartModel(
         CTL_INF("Model '" + model_handle + "' is already loaded");
         return true;
       } else {
+        auto root = json_helper::ParseJsonString(res->body);       
         CTL_ERR("Model failed to load with status code: " << res->status);
-        return cpp::fail("Model failed to load with status code: " +
-                         std::to_string(res->status));
+        return cpp::fail("Model failed to start: " + root["message"].asString());
       }
     } else {
       auto err = res.error();

engine/test/components/test_json_helper.cc

@@ -0,0 +1,35 @@
+#include <gtest/gtest.h>
+#include <json/json.h>
+#include <string>
+#include "utils/json_helper.h"
+
+// Test Suite
+TEST(ParseJsonStringTest, ValidJsonObject) {
+    std::string json_str = R"({"name": "John", "age": 30})";
+    Json::Value result = json_helper::ParseJsonString(json_str);
+
+    EXPECT_EQ(result["name"].asString(), "John");
+    EXPECT_EQ(result["age"].asInt(), 30);
+}
+
+TEST(ParseJsonStringTest, ValidJsonArray) {
+    std::string json_str = R"([1, 2, 3, 4, 5])";
+    Json::Value result = json_helper::ParseJsonString(json_str);
+
+    EXPECT_EQ(result.size(), 5);
+    EXPECT_EQ(result[0].asInt(), 1);
+}
+
+TEST(ParseJsonStringTest, InvalidJson) {
+    std::string json_str = R"({"name": "John", "age": )"; 
+    Json::Value result = json_helper::ParseJsonString(json_str);
+
+    EXPECT_TRUE(result["age"].isNull());
+}
+
+TEST(ParseJsonStringTest, EmptyString) {
+    std::string json_str = "";
+    Json::Value result = json_helper::ParseJsonString(json_str);
+
+    EXPECT_TRUE(result.isNull()); 
+}

engine/utils/json_helper.h

@@ -0,0 +1,11 @@
+#pragma once
+#include <json/json.h>
+#include <string>
+namespace json_helper {
+inline Json::Value ParseJsonString(const std::string& json_str) {
+  Json::Value root;
+  Json::Reader reader;
+  reader.parse(json_str, root);
+  return root;
+}
+}