text: #include <Functions/IFunctionImpl.h>
  #include <Functions/FunctionFactory.h>
  #include <Interpreters/Context.h>
  #include <DataTypes/DataTypeString.h>
  #include <DataTypes/DataTypeUUID.h>
  #include <Access/QuotaContext.h>
  #include <Core/Field.h>
  
  
  namespace DB
  {
  
  class FunctionCurrentQuota : public IFunction
  {
      const String quota_name;
  
  public:
      static constexpr auto name = "currentQuota";
      static FunctionPtr create(const Context & context)
      {
          return std::make_shared<FunctionCurrentQuota>(context.getQuota()->getUsageInfo().quota_name);
      }
  
      explicit FunctionCurrentQuota(const String & quota_name_) : quota_name{quota_name_}
      {
      }
  
      String getName() const override
      {
          return name;
      }
      size_t getNumberOfArguments() const override
      {
          return 0;
      }
  
      DataTypePtr getReturnTypeImpl(const DataTypes & /*arguments*/) const override
      {
          return std::make_shared<DataTypeString>();
      }
  
      bool isDeterministic() const override { return false; }
  
      void executeImpl(Block & block, const ColumnNumbers &, size_t result, size_t input_rows_count) override
      {
          block.getByPosition(result).column = DataTypeString().createColumnConst(input_rows_count, quota_name);
      }
  };
  
  
  class FunctionCurrentQuotaId : public IFunction
  {
      const UUID quota_id;
  
  public:
      static constexpr auto name = "currentQuotaID";
      static FunctionPtr create(const Context & context)
      {
          return std::make_shared<FunctionCurrentQuotaId>(context.getQuota()->getUsageInfo().quota_id);
      }
  
      explicit FunctionCurrentQuotaId(const UUID quota_id_) : quota_id{quota_id_}
      {
      }
  
      String getName() const override
      {
          return name;
      }
      size_t getNumberOfArguments() const override
      {
          return 0;
      }
  
      DataTypePtr getReturnTypeImpl(const DataTypes & /*arguments*/) const override
      {
          return std::make_shared<DataTypeUUID>();
      }
  
      bool isDeterministic() const override { return false; }
  
      void executeImpl(Block & block, const ColumnNumbers &, size_t result, size_t input_rows_count) override
      {
          block.getByPosition(result).column = DataTypeUUID().createColumnConst(input_rows_count, quota_id);
      }
  };
  
  
  class FunctionCurrentQuotaKey : public IFunction
  {
      const String quota_key;
  
  public:
      static constexpr auto name = "currentQuotaKey";
      static FunctionPtr create(const Context & context)
      {
          return std::make_shared<FunctionCurrentQuotaKey>(context.getQuota()->getUsageInfo().quota_key);
      }
  
      explicit FunctionCurrentQuotaKey(const String & quota_key_) : quota_key{quota_key_}
      {
      }
  
      String getName() const override
      {
          return name;
      }
      size_t getNumberOfArguments() const override
      {
          return 0;
      }
  
      DataTypePtr getReturnTypeImpl(const DataTypes & /*arguments*/) const override
      {
          return std::make_shared<DataTypeString>();
      }
  
      bool isDeterministic() const override { return false; }
  
      void executeImpl(Block & block, const ColumnNumbers &, size_t result, size_t input_rows_count) override
      {
          block.getByPosition(result).column = DataTypeString().createColumnConst(input_rows_count, quota_key);
      }
  };
  
  
  void registerFunctionCurrentQuota(FunctionFactory & factory)
  {
      factory.registerFunction<FunctionCurrentQuota>();
      factory.registerFunction<FunctionCurrentQuotaId>();
      factory.registerFunction<FunctionCurrentQuotaKey>();
  }
  
  }
  