skident / eos_cpp

Easy serialization and deserialization of simple data structures

eos_cpp - Easy Object Serialization

Aim

Easy serialization and deserialization of data structures: to/from JSON, to std::string and so on. Any new serializer can be added just by implementing a static serialize method

template <class InSerializable>
static void serialize(OutSerialized& outSerialized, const InSerializable& inSerializable)

For example you can implement SqlInsert serializer and SqlSelect serializer/deserializer, it will simplify your client code to something like this:

User user = {"my_login", "my_password"};
DataSource::get().insert(user); <--- serialization inside the 'insert' method based on which datasource is used (Sqlite, MySQL, or something else).

Examples

I define next data structure

struct User
{
EOS_PROPERTY(int, id);
EOS_PROPERTY(string, login);
EOS_PROPERTY(string, password);
EOS_PROPERTY(bool, activated);
EOS_PROPERTY(unsigned int, timestamp);
};

namespace Factory
{
    User createUser()
    {
        User user = {1, std::string("user_login"), std::string("secure_password"), true, 1582359281};
        return user;
    }
}

I want to create a JSON object from this data structure to send it to the remote service

User user = Factory::createUser();
std::string jsonStr = eos::toJson(user);

jsonStr is ready for using.

let's deserialize it back:

User user2;
eos::fromJson(jsonStr, user2);

auto user3 = eos::fromJson<User>(jsonStr);

Print results to console:

std::cout << "[serialized user] " << jsonStr << std::endl;
Serializer<StdOstream>::serialize(std::cout << "[deserialized user] ", user2);

Console output:

[serialized user] {"activated":true,"id":1,"login":"user_login","password":"secure_password","timestamp":1582359281}
[deserialized user] id : 1;login : user_login;password : secure_password;activated : 1;timestamp : 1582359281;

Thrid party libraries:

1. magic_get (boost::pfr) https://github.com/apolukhin/magic_get
2. nlohmann json https://github.com/nlohmann/json

Solution structure

1. third - third party libraries
2. types - classes, macro and utils for a compile time reflection
3. serializer - classes for serialization: NlohmannJSON, StdString, StdOstream. TSerializer is kind of base class for all serializers (it is no necessary to use it)
4. utils - util for converting std::tuple to structure
5. main.cpp - examples of serialization and deserialization (if possible).

Build system:

Cmake

C++ standard:

C++17

eos_cpp's Issues

SFINAE check for operators

Consider enabling operators in a Property class if those operators are available in a wrapped type.
For example std::vector and std::map have an operator[] and if there is no specialization of a Property class for those types, you cannot use operator[] directly, but need to get .value first.

Without specialization

 auto& title = config.app->main_menu.value[0].title;

With specialization

 auto& title = config.app->main_menu[0].title;