handleData

 EspMessageReader * reader = esp_subscriber_event_get_reader(event, error);
	 EspStream * stream = esp_message_reader_get_stream(reader, error);
	 const EspSchema * schema = esp_stream_get_schema(stream, error);
	 EspRowReader * row_reader;
	int32_t int_value;   int64_t long_value; time_t date_value; double double_value;
	 int numcolumns, numrows, type;
	 rc = esp_schema_get_numcolumns(schema, &numcolumns, error);
	 while ((row_reader = esp_message_reader_next_row(reader, error)) != NULL) {
		 for (int i = 0; i < numcolumns; ++i) {
		        rc = esp_schema_get_column_type(schema, i, &type, error);
		        switch(type){
			case ESP_DATATYPE_INTEGER:
			         rc = esp_row_reader_get_integer(row_reader, i, &int_value, error);
			         break;
			case ESP_DATATYPE_LONG:
			         rc = esp_row_reader_get_long(row_reader, i, &long_value, error);
			         break;
			case ESP_DATATYPE_DATE:
			         rc = esp_row_reader_get_date(row_reader, i, &date_value, error);
			         break;
		        }
		}