icinga2/lib/base/serializer.cpp

/******************************************************************************
* Icinga 2                                                                   *
* Copyright (C) 2012-2013 Icinga Development Team (http://www.icinga.org/)   *
*                                                                            *
* This program is free software; you can redistribute it and/or              *
* modify it under the terms of the GNU General Public License                *
* as published by the Free Software Foundation; either version 2             *
* of the License, or (at your option) any later version.                     *
*                                                                            *
* This program is distributed in the hope that it will be useful,            *
* but WITHOUT ANY WARRANTY; without even the implied warranty of             *
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the              *
* GNU General Public License for more details.                               *
*                                                                            *
* You should have received a copy of the GNU General Public License          *
* along with this program; if not, write to the Free Software Foundation     *
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.             *
******************************************************************************/

#include "base/serializer.h"
#include "base/type.h"
#include "base/application.h"
#include "base/objectlock.h"
#include <boost/foreach.hpp>
#include <boost/tuple/tuple.hpp>
#include <cJSON.h>

using namespace icinga;

/**
 * Serializes a Value into a JSON string.
 *
 * @returns A string representing the Value.
 */
String icinga::JsonSerialize(const Value& value)
{
	cJSON *json = value.ToJson();

	char *jsonString;

	if (Application::IsDebugging())
		jsonString = cJSON_Print(json);
	else
		jsonString = cJSON_PrintUnformatted(json);

	cJSON_Delete(json);

	String result = jsonString;

	free(jsonString);

	return result;
}

/**
 * Deserializes the string representation of a Value.
 *
 * @param data A JSON string obtained from JsonSerialize
 * @returns The newly deserialized Value.
 */
Value icinga::JsonDeserialize(const String& data)
{
	cJSON *json = cJSON_Parse(data.CStr());

	if (!json)
		BOOST_THROW_EXCEPTION(std::runtime_error("Invalid JSON String: " + data));

	Value value = Value::FromJson(json);
	cJSON_Delete(json);

	return value;
}

static Array::Ptr SerializeArray(const Array::Ptr& input, int attributeTypes)
{
	Array::Ptr result = make_shared<Array>();

	ObjectLock olock(input);

	BOOST_FOREACH(const Value& value, input) {
		result->Add(Serialize(value, attributeTypes));
	}

	return result;
}

static Dictionary::Ptr SerializeDictionary(const Dictionary::Ptr& input, int attributeTypes)
{
	Dictionary::Ptr result = make_shared<Dictionary>();

	ObjectLock olock(input);

	String key;
	Value value;
	BOOST_FOREACH(boost::tie(key, value), input) {
		result->Set(key, Serialize(value, attributeTypes));
	}

	return result;
}

static Object::Ptr SerializeObject(const Object::Ptr& input, int attributeTypes)
{
	const Type *type = input->GetReflectionType();

	VERIFY(type);

	Dictionary::Ptr fields = make_shared<Dictionary>();

	for (int i = 0; i < type->GetFieldCount(); i++) {
		Field field = type->GetFieldInfo(i);

		if ((field.Attributes & attributeTypes) == 0)
			continue;

		fields->Set(field.Name, Serialize(input->GetField(i), attributeTypes));
	}

	fields->Set("__type", type->GetName());

	return fields;
}

static Array::Ptr DeserializeArray(const Array::Ptr& input, int attributeTypes)
{
	Array::Ptr result = make_shared<Array>();

	ObjectLock olock(input);

	BOOST_FOREACH(const Value& value, input) {
		result->Add(Deserialize(value, attributeTypes));
	}

	return result;
}

static Dictionary::Ptr DeserializeDictionary(const Dictionary::Ptr& input, int attributeTypes)
{
	Dictionary::Ptr result = make_shared<Dictionary>();

	ObjectLock olock(input);

	String key;
	Value value;
	BOOST_FOREACH(boost::tie(key, value), input) {
		result->Set(key, Deserialize(value, attributeTypes));
	}

	return result;
}

static Object::Ptr DeserializeObject(const Object::Ptr& object, const Dictionary::Ptr& input, int attributeTypes)
{
	const Type *type;

	if (object)
		type = object->GetReflectionType();
	else
		type = Type::GetByName(input->Get("__type"));

	if (!type)
		return object;

	Object::Ptr instance = object;

	if (!instance)
		instance = type->Instantiate();

	for (int i = 0; i < type->GetFieldCount(); i++) {
		Field field = type->GetFieldInfo(i);

		if ((field.Attributes & attributeTypes) == 0)
			continue;

		if (!input->Contains(field.Name))
			continue;

		try {
			instance->SetField(i, Deserialize(input->Get(field.Name), attributeTypes));
		} catch (const std::exception&) {
			instance->SetField(i, Empty);
		}
	}

	return instance;
}

Value icinga::Serialize(const Value& value, int attributeTypes)
{
	if (!value.IsObject())
		return value;

	Object::Ptr input = value;

	Array::Ptr array = dynamic_pointer_cast<Array>(input);

	if (array != NULL)
		return SerializeArray(array, attributeTypes);

	Dictionary::Ptr dict = dynamic_pointer_cast<Dictionary>(input);

	if (dict != NULL)
		return SerializeDictionary(dict, attributeTypes);

	return SerializeObject(input, attributeTypes);
}

Value icinga::Deserialize(const Value& value, int attributeTypes)
{
	return Deserialize(Object::Ptr(), value, attributeTypes);
}

Value icinga::Deserialize(const Object::Ptr& object, const Value& value, int attributeTypes)
{
	if (!value.IsObject())
		return value;

	Object::Ptr input = value;

	Array::Ptr array = dynamic_pointer_cast<Array>(input);

	if (array != NULL)
		return DeserializeArray(array, attributeTypes);

	Dictionary::Ptr dict = dynamic_pointer_cast<Dictionary>(input);

	ASSERT(dict != NULL);

	if (!dict->Contains("__type"))
		return DeserializeDictionary(dict, attributeTypes);

	return DeserializeObject(object, dict, attributeTypes);
}