pb2json.cpp

/*
 * The MIT License (MIT)
 *
 * Copyright (c) 2013 shafreeck renenglish at gmail dot com
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy of
 * this software and associated documentation files (the "Software"), to deal in
 * the Software without restriction, including without limitation the rights to
 * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
 * the Software, and to permit persons to whom the Software is furnished to do so,
 * subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
 * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
 * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
 * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */

#include "pb2json.h"
#include <stdint.h>

//using std::string;
std::string hex_encode(const std::string& input)
{
	static const char* const lut = "0123456789abcdef";
	size_t len = input.length();

	std::string output;
	output.reserve(2 * len);
	for (size_t i = 0; i < len; ++i)
	{
		const unsigned char c = input[i];
		output.push_back(lut[c >> 4]);
		output.push_back(lut[c & 15]);
	}
	return output;
}
char * pb2json(const google::protobuf::Message &msg)
{
	json_t *root = parse_msg(&msg);
	char *json = json_dumps(root,0);
	json_decref(root);
	return json; // should be freed by caller
}
char * pb2json( google::protobuf::Message *msg,const char *buf ,int len)
{
	GOOGLE_PROTOBUF_VERIFY_VERSION;
	std::string s (buf,len);
	msg->ParseFromString(s);
	json_t *root = parse_msg(msg);
	char *json = json_dumps(root,0);
	json_decref(root);
	google::protobuf::ShutdownProtobufLibrary();
	return json; // should be freed by caller
}
json_t *parse_repeated_field(const google::protobuf::Message *msg,const google::protobuf::Reflection * ref,const google::protobuf::FieldDescriptor *field)
{
	size_t count = ref->FieldSize(*msg,field);
	json_t *arr = json_array();	
	if(!arr)return NULL;
	switch(field->cpp_type())	
	{
		case google::protobuf::FieldDescriptor::CPPTYPE_DOUBLE:
			for(size_t i = 0 ; i != count ; ++i)
			{
				double	value1 = ref->GetRepeatedDouble(*msg,field,i);
				json_array_append_new(arr,json_real(value1));	
			}
			break;
		case google::protobuf::FieldDescriptor::CPPTYPE_FLOAT:
			for(size_t i = 0 ; i != count ; ++i)
			{
				float value2 = ref->GetRepeatedFloat(*msg,field,i);
				json_array_append_new(arr,json_real(value2));	
			}
			break;
		case google::protobuf::FieldDescriptor::CPPTYPE_INT64:
			for(size_t i = 0 ; i != count ; ++i)
			{
				int64_t value3 = ref->GetRepeatedInt64(*msg,field,i);
				json_array_append_new(arr,json_integer(value3))	;
			}
			break;
		case google::protobuf::FieldDescriptor::CPPTYPE_UINT64:
			for(size_t i = 0 ; i != count ; ++i)
			{
				uint64_t value4 = ref->GetRepeatedUInt64(*msg,field,i);
				json_array_append_new(arr,json_integer(value4));	
			}
			break;
		case google::protobuf::FieldDescriptor::CPPTYPE_INT32:
			for(size_t i = 0 ; i != count ; ++i)
			{
				int32_t value5 = ref->GetRepeatedInt32(*msg,field,i);
				json_array_append_new(arr,json_integer(value5));	
			}
			break;
		case google::protobuf::FieldDescriptor::CPPTYPE_UINT32:
			for(size_t i = 0 ; i != count ; ++i)
			{
				uint32_t value6 = ref->GetRepeatedUInt32(*msg,field,i);
				json_array_append_new(arr,json_integer(value6));	
			}
			break;
		case google::protobuf::FieldDescriptor::CPPTYPE_BOOL:
			for(size_t i = 0 ; i != count ; ++i)
			{
				bool value7 = ref->GetRepeatedBool(*msg,field,i);
				json_array_append_new(arr,value7?json_true():json_false())	;
			}
			break;
		case google::protobuf::FieldDescriptor::CPPTYPE_STRING:
			for(size_t i = 0 ; i != count ; ++i)
			{
				std::string value8 = ref->GetRepeatedString(*msg,field,i);
				json_array_append_new(arr,json_string(value8.c_str()));	
			}
			break;
		case google::protobuf::FieldDescriptor::CPPTYPE_MESSAGE:
			for(size_t i = 0 ; i != count ; ++i)
			{
				const google::protobuf::Message *value9 = &(ref->GetRepeatedMessage(*msg,field,i));
				json_array_append_new(arr,parse_msg(value9));
			}
			break;
		case google::protobuf::FieldDescriptor::CPPTYPE_ENUM:
			for(size_t i = 0 ; i != count ; ++i)
			{
				const google::protobuf::EnumValueDescriptor* value10 = ref->GetRepeatedEnum(*msg,field,i);
				json_array_append_new(arr,json_integer(value10->number()));	
			}
			break;
		default:
			break;
	}
	return arr;
}
json_t *parse_msg(const google::protobuf::Message *msg)
{
	const google::protobuf::Descriptor *d = msg->GetDescriptor();
	if(!d)return NULL;
	size_t count = d->field_count();
	json_t *root = json_object();
	if(!root)return NULL;
	for (size_t i = 0; i != count ; ++i)
	{
		const google::protobuf::FieldDescriptor *field = d->field(i);
		if(!field)return NULL;

		const google::protobuf::Reflection *ref = msg->GetReflection();
		if(!ref)return NULL;
		const char *name = field->name().c_str();
		if(field->is_repeated())
			json_object_set_new(root,name,parse_repeated_field(msg,ref,field));
		if(!field->is_repeated() && ref->HasField(*msg,field))
		{

			double value1;
			float value2;
			int64_t value3;
			uint64_t value4;
			int32_t value5;
			uint32_t value6;
			bool value7;
			std::string value8;
			const google::protobuf::Message *value9;
			const google::protobuf::EnumValueDescriptor *value10;

			switch (field->cpp_type())
			{
				case google::protobuf::FieldDescriptor::CPPTYPE_DOUBLE:
					value1 = ref->GetDouble(*msg,field);
					json_object_set_new(root,name,json_real(value1));	
					break;
				case google::protobuf::FieldDescriptor::CPPTYPE_FLOAT:
					value2 = ref->GetFloat(*msg,field);
					json_object_set_new(root,name,json_real(value2));	
					break;
				case google::protobuf::FieldDescriptor::CPPTYPE_INT64:
					value3 = ref->GetInt64(*msg,field);
					json_object_set_new(root,name,json_integer(value3))	;
					break;
				case google::protobuf::FieldDescriptor::CPPTYPE_UINT64:
					value4 = ref->GetUInt64(*msg,field);
					json_object_set_new(root,name,json_integer(value4));	
					break;
				case google::protobuf::FieldDescriptor::CPPTYPE_INT32:
					value5 = ref->GetInt32(*msg,field);
					json_object_set_new(root,name,json_integer(value5));	
					break;
				case google::protobuf::FieldDescriptor::CPPTYPE_UINT32:
					value6 = ref->GetUInt32(*msg,field);
					json_object_set_new(root,name,json_integer(value6));	
					break;
				case google::protobuf::FieldDescriptor::CPPTYPE_BOOL:
					value7 = ref->GetBool(*msg,field);
					json_object_set_new(root,name,value7?json_true():json_false())	;
					break;
				case google::protobuf::FieldDescriptor::CPPTYPE_STRING:
					if (field->type() == google::protobuf::FieldDescriptor::TYPE_BYTES) {
						value8 = hex_encode(ref->GetString(*msg,field));
					} else {
						value8 = ref->GetString(*msg,field);
					}
					json_object_set_new(root,name,json_string(value8.c_str()));	
					break;
				case google::protobuf::FieldDescriptor::CPPTYPE_MESSAGE:
					value9 = &(ref->GetMessage(*msg,field));
					json_object_set_new(root,name,parse_msg(value9));
					break;
				case google::protobuf::FieldDescriptor::CPPTYPE_ENUM:
					value10 = ref->GetEnum(*msg,field);
					json_object_set_new(root,name,json_integer(value10->number()));	
					break;
				default:
					break;
			}

		}

	}
	return root;

}