[native] Add support for optional velox.properties file

presto-native-execution/presto_cpp/main/PrestoServer.cpp

@@ -152,8 +152,9 @@ void PrestoServer::run() {
         fmt::format("{}/config.properties", configDirectoryPath_));
     nodeConfig->initialize(
         fmt::format("{}/node.properties", configDirectoryPath_));
+    // velox.properties is optional.
     baseVeloxQueryConfig->initialize(
-        fmt::format("{}/velox.properties", configDirectoryPath_));
+        fmt::format("{}/velox.properties", configDirectoryPath_), true);
 
     if (systemConfig->enableRuntimeMetricsCollection()) {
       enableRuntimeMetricReporting();

presto-native-execution/presto_cpp/main/common/Configs.cpp

@@ -47,9 +47,14 @@ std::string bool2String(bool value) {
 ConfigBase::ConfigBase()
     : config_(std::make_unique<velox::core::MemConfig>()) {}
 
-void ConfigBase::initialize(const std::string& filePath) {
-  // See if we want to create a mutable config.
-  auto values = util::readConfig(fs::path(filePath));
+void ConfigBase::initialize(const std::string& filePath, bool optionalConfig) {
+  auto path = fs::path(filePath);
+  std::unordered_map<std::string, std::string> values;
+  if (!optionalConfig || fs::exists(path)) {
+    // See if we want to create a mutable config.
+    values = util::readConfig(path);
+  }
+
   filePath_ = filePath;
   checkRegisteredProperties(values);
   updateLoadedValues(values);

presto-native-execution/presto_cpp/main/common/Configs.h

@@ -29,7 +29,8 @@ class ConfigBase {
   /// Reads configuration properties from the specified file. Must be called
   /// before calling any of the getters below.
   /// @param filePath Path to configuration file.
-  void initialize(const std::string& filePath);
+  /// @param optionalConfig Specify if the configuration file is optional.
+  void initialize(const std::string& filePath, bool optionalConfig = false);
 
   /// Allows individual config to manipulate just-loaded-from-file key-value map
   /// before it is used to initialize the config.