szaszm commented on a change in pull request #976: URL: https://github.com/apache/nifi-minifi-cpp/pull/976#discussion_r561927345
########## File path: extensions/windows-event-log/wel/JSONUtils.cpp ########## @@ -0,0 +1,170 @@ +/** + * Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. + * The ASF licenses this file to You under the Apache License, Version 2.0 + * (the "License"); you may not use this file except in compliance with + * the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#include "JSONUtils.h" + +#include <vector> +#include <string> +#include <functional> + +#include <pugixml.hpp> + +#include "rapidjson/document.h" +#include "rapidjson/writer.h" +#include "rapidjson/stringbuffer.h" +#include "rapidjson/prettywriter.h" + +#include "gsl/gsl-lite.hpp"; + +namespace org { +namespace apache { +namespace nifi { +namespace minifi { +namespace wel { + +namespace { + +rapidjson::Value xmlElementToJSON(const pugi::xml_node& node, rapidjson::Document& doc) { + gsl_Expects(node.type() == pugi::xml_node_type::node_element); + rapidjson::Value object(rapidjson::kObjectType); + object.AddMember("name", rapidjson::StringRef(node.name()), doc.GetAllocator()); + auto& attributes = object.AddMember("attributes", rapidjson::kObjectType, doc.GetAllocator())["attributes"]; + for (const auto& attr : node.attributes()) { + attributes.AddMember(rapidjson::StringRef(attr.name()), rapidjson::StringRef(attr.value()), doc.GetAllocator()); + } + auto& children = object.AddMember("children", rapidjson::kArrayType, doc.GetAllocator())["children"]; + for (const auto& child : node.children()) { + if (child.type() == pugi::xml_node_type::node_element) { + children.PushBack(xmlElementToJSON(child, doc), doc.GetAllocator()); + } + } + object.AddMember("text", rapidjson::StringRef(node.text().get()), doc.GetAllocator()); + return object; +} + +rapidjson::Value xmlDocumentToJSON(const pugi::xml_node& node, rapidjson::Document& doc) { + gsl_Expects(node.type() == pugi::xml_node_type::node_document); + rapidjson::Value children(rapidjson::kArrayType); + for (const auto& child : node.children()) { + if (child.type() == pugi::xml_node_type::node_element) { + children.PushBack(xmlElementToJSON(child, doc), doc.GetAllocator()); + } + } + return children; +} + +rapidjson::Document toJSONImpl(const pugi::xml_node& root, bool flatten) { + rapidjson::Document doc{rapidjson::kObjectType}; + + auto event_xml = root.child("Event"); + + { + auto system_xml = event_xml.child("System"); + auto& system = flatten ? doc : doc.AddMember("System", rapidjson::kObjectType, doc.GetAllocator())["System"]; + + { + auto provider_xml = system_xml.child("Provider"); + auto& provider = flatten ? doc : system.AddMember("Provider", rapidjson::kObjectType, doc.GetAllocator())["Provider"]; + provider.AddMember("Name", rapidjson::StringRef(provider_xml.attribute("Name").value()), doc.GetAllocator()); + provider.AddMember("Guid", rapidjson::StringRef(provider_xml.attribute("Guid").value()), doc.GetAllocator()); + } + + system.AddMember("EventID", rapidjson::StringRef(system_xml.child("EventID").text().get()), doc.GetAllocator()); + system.AddMember("Version", rapidjson::StringRef(system_xml.child("Version").text().get()), doc.GetAllocator()); + system.AddMember("Level", rapidjson::StringRef(system_xml.child("Level").text().get()), doc.GetAllocator()); + system.AddMember("Task", rapidjson::StringRef(system_xml.child("Task").text().get()), doc.GetAllocator()); + system.AddMember("Opcode", rapidjson::StringRef(system_xml.child("Opcode").text().get()), doc.GetAllocator()); + system.AddMember("Keywords", rapidjson::StringRef(system_xml.child("Keywords").text().get()), doc.GetAllocator()); + + { + auto timeCreated_xml = system_xml.child("TimeCreated"); + auto& timeCreated = flatten ? doc : system.AddMember("TimeCreated", rapidjson::kObjectType, doc.GetAllocator())["TimeCreated"]; + timeCreated.AddMember("SystemTime", rapidjson::StringRef(timeCreated_xml.attribute("SystemTime").value()), doc.GetAllocator()); + } + + system.AddMember("EventRecordID", rapidjson::StringRef(system_xml.child("EventRecordID").text().get()), doc.GetAllocator()); + + { + auto correlation_xml = system_xml.child("Correlation"); + auto& correlation = flatten ? doc : system.AddMember("Correlation", rapidjson::kObjectType, doc.GetAllocator())["Correlation"]; + correlation.AddMember("ActivityID", rapidjson::StringRef(correlation_xml.attribute("ActivityID").value()), doc.GetAllocator()); + } + + { + auto execution_xml = system_xml.child("Execution"); + auto& execution = flatten ? doc : system.AddMember("Execution", rapidjson::kObjectType, doc.GetAllocator())["Execution"]; + execution.AddMember("ProcessID", rapidjson::StringRef(execution_xml.attribute("ProcessID").value()), doc.GetAllocator()); + execution.AddMember("ThreadID", rapidjson::StringRef(execution_xml.attribute("ThreadID").value()), doc.GetAllocator()); + } + + system.AddMember("Channel", rapidjson::StringRef(system_xml.child("Channel").text().get()), doc.GetAllocator()); + system.AddMember("Computer", rapidjson::StringRef(system_xml.child("Computer").text().get()), doc.GetAllocator()); + } + + { + auto eventData_xml = event_xml.child("EventData"); + // create EventData subarray even if flatten requested + doc.AddMember("EventData", rapidjson::kArrayType, doc.GetAllocator()); + for (const auto& data : eventData_xml.children()) { + auto name_attr = data.attribute("Name"); + rapidjson::Value item(rapidjson::kObjectType); + item.AddMember("Name", rapidjson::StringRef(name_attr.value()), doc.GetAllocator()); + item.AddMember("Content", rapidjson::StringRef(data.text().get()), doc.GetAllocator()); + item.AddMember("Type", rapidjson::StringRef(data.name()), doc.GetAllocator()); + // we need to query EventData because a reference to it wouldn't be stable, as we + // possibly add members to its parent which could result in reallocation + doc["EventData"].PushBack(item, doc.GetAllocator()); + // check collision + if (flatten && !name_attr.empty() && !doc.HasMember(name_attr.value())) { + doc.AddMember(rapidjson::StringRef(name_attr.value()), rapidjson::StringRef(data.text().get()), doc.GetAllocator()); Review comment: If I understand correctly, using `rapidjson::StringRef` all over the place means that the returned json object is valid only as long as the original pugi xml object is valid and unchanged. If so, there should be a big loud warning on the function to warn the next caller about this. ########## File path: extensions/windows-event-log/wel/JSONUtils.h ########## @@ -0,0 +1,80 @@ +/** + * Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. + * The ASF licenses this file to You under the Apache License, Version 2.0 + * (the "License"); you may not use this file except in compliance with + * the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#pragma once + +#undef RAPIDJSON_ASSERT +#define RAPIDJSON_ASSERT(x) if (!(x)) throw std::logic_error("rapidjson exception"); // NOLINT + +#include <pugixml.hpp> + +#include <stdexcept> // for std::logic_error +#include "rapidjson/document.h" + +namespace org { +namespace apache { +namespace nifi { +namespace minifi { +namespace wel { + +/** + * !!WARNING!! the json document must not outlive the xml argument + * + * Converts each xml element node to a json object of + * the form {name: String, attributes: Object, children: Array, text: String} + * Aims to preserve most of the input xml structure. + */ +rapidjson::Document toRawJSON(const pugi::xml_node& root); + +/** + * !!WARNING!! the json document must not outlive the xml argument Review comment: I would also explain why: ```suggestion * !!WARNING!! The json document must not outlive the xml argument. For better performance, * the created json document stores references to values in the xml node. Accessing the * json document after the xml node has been destroyed results in undefined behavior. ``` ########## File path: extensions/windows-event-log/wel/JSONUtils.h ########## @@ -0,0 +1,80 @@ +/** + * Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. + * The ASF licenses this file to You under the Apache License, Version 2.0 + * (the "License"); you may not use this file except in compliance with + * the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#pragma once + +#undef RAPIDJSON_ASSERT +#define RAPIDJSON_ASSERT(x) if (!(x)) throw std::logic_error("rapidjson exception"); // NOLINT + +#include <pugixml.hpp> + +#include <stdexcept> // for std::logic_error +#include "rapidjson/document.h" + +namespace org { +namespace apache { +namespace nifi { +namespace minifi { +namespace wel { + +/** + * !!WARNING!! the json document must not outlive the xml argument + * + * Converts each xml element node to a json object of + * the form {name: String, attributes: Object, children: Array, text: String} + * Aims to preserve most of the input xml structure. + */ +rapidjson::Document toRawJSON(const pugi::xml_node& root); + +/** + * !!WARNING!! the json document must not outlive the xml argument Review comment: I would also explain why: ```suggestion * !!WARNING!! The json document must not outlive the xml argument. For better performance, * the created json document stores references to values in the xml node. Accessing the * json document after the xml node has been changed or destroyed results in undefined behavior. ``` ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: [email protected]
