Fix ctr_prediction model

demo-serving/conf/model_toolkit.prototxt

@@ -28,4 +28,6 @@ engines {
   runtime_thread_num: 0
   batch_infer_size: 0
   enable_batch_align: 0
+  sparse_param_service_type: REMOTE
+  sparse_param_service_table_name: "dict"
 }

demo-serving/op/ctr_prediction_op.cpp

@@ -102,25 +102,57 @@ int CTRPredictionOp::inference() {
   predictor::KVManager &kv_manager = predictor::KVManager::instance();
   const predictor::KVInfo *kvinfo =
       kv_manager.get_kv_info(CTR_PREDICTION_MODEL_NAME);
-  if (kvinfo != NULL) {
+  if (kvinfo == NULL) {
+    LOG(ERROR) << "Sparse param service info not found for model "
+               << CTR_PREDICTION_MODEL_NAME
+               << ". Maybe forgot to specify sparse_param_service_type and "
+               << "sparse_param_service_table_name in "
+               << "conf/model_toolkit.prototxt";
+    fill_response_with_message(res, -1, "Sparse param service info not found");
+    return 0;
+  }
+
   std::string table_name;
   if (kvinfo->sparse_param_service_type != configure::EngineDesc::NONE) {
     table_name = kvinfo->sparse_param_service_table_name;
+    if (table_name.empty()) {
+      LOG(ERROR) << "sparse_param_service_table_name not specified. "
+                 << "Please specify it in conf/model_toolkit.protxt for model "
+                 << CTR_PREDICTION_MODEL_NAME;
+      fill_response_with_message(
+          res, -1, "sparse_param_service_table_name not specified");
+    }
   }
 
   if (kvinfo->sparse_param_service_type == configure::EngineDesc::LOCAL) {
     // Query local KV service
+    LOG(ERROR) << "Local kv service not supported for model "
+               << CTR_PREDICTION_MODEL_NAME;
+
+    fill_response_with_message(
+        res, -1, "Local kv service not supported for this model");
+    return 0;
   } else if (kvinfo->sparse_param_service_type ==
              configure::EngineDesc::REMOTE) {
     int ret = cube->seek(table_name, keys, &values);
     if (ret != 0) {
       fill_response_with_message(res, -1, "Query cube for embeddings error");
       LOG(ERROR) << "Query cube for embeddings error";
-        return -1;
+      return 0;
     }
   }
 
-#if 0
+  if (values.size() != keys.size()) {
+    LOG(ERROR) << "Sparse embeddings not ready; "
+               << "maybe forgot to set sparse_param_service_type and "
+               << "sparse_param_sevice_table_name for "
+               << CTR_PREDICTION_MODEL_NAME
+               << " in conf/model_toolkit.prototxt";
+    fill_response_with_message(
+        res, -1, "Sparse param service not configured properly");
+    return 0;
+  }
+
   for (int i = 0; i < keys.size(); ++i) {
     std::ostringstream oss;
     oss << keys[i] << ": ";
@@ -131,13 +163,13 @@ int CTRPredictionOp::inference() {
                    << CTR_PREDICTION_EMBEDDING_SIZE;
     }
 
+#if 0
       for (int j = 0; j < values[i].buff.size(); ++j) {
         oss << std::hex << std::uppercase << std::setw(2) << std::setfill('0')
             << (static_cast<int>(value[j]) & 0xff);
       }
 
       LOG(INFO) << oss.str().c_str();
-    }
 #endif
   }