kizunapi

A set of header-only C++ classes for type conversion between C++ and JavaScript using Node-API.

Kizunapi makes writing library bindings easy: you don't write wrapper code for each API, instead you provide minimal information about types and kizunapi will do the rest of the work via C++ type deduction.

This project is at early stage, behavior of APIs may change without notice.

Usage

1. Add this module to dependencies in package.json:

  "dependencies": {
    "kizunapi": "*",
  }

2. Add include directory in binding.gyp:

  'include_dirs': ["<!(node -p \"require('kizunapi').include_dir\")"],

3. Enable C++17 in bindings.gyp:

  'cflags_cc': [ '-std=c++17' ],
  'xcode_settings': { 'OTHER_CFLAGS': [ '-std=c++17'] },
  'msvs_settings': {
    'VCCLCompilerTool': {
      'AdditionalOptions': [ '/std:c++17' ],
    },
  },

4. In source code:

#include <kizunapi.h>

Docs

• Tutorial

Example

This example maps C++ classes with inheritance relationship to JavaScript using non-intrusive APIs.

#include <kizunapi.h>

// The classes to be exported to JavaScript.
class Parent {
 public:
  int Year() const {
    return 1989;
  }
};

class Child : public Parent {
 public:
  Child(int month, int day) : month_(month), day_(day) {}

  std::string Date() const {
    return std::to_string(month_) + std::to_string(day_);
  }

 private:
  int month_;
  int day_;
};

// Type information provided to kizunapi.
namespace ki {

template<>
struct Type<Parent> {
  static constexpr const char* name = "Parent";
  static Parent* Constructor() {
    return new Parent();
  }
  static void Destructor(Parent* ptr) {
    delete ptr;
  }
  static void Define(napi_env env,
                     napi_value constructor,
                     napi_value prototype) {
    Set(env, prototype, "year", &Parent::Year);
  }
};

template<>
struct Type<Child> {
  using Base = Parent;
  static constexpr const char* name = "Child";
  static Child* Constructor(int month, int day) {
    return new Child(month, day);
  }
  static void Destructor(Child* ptr) {
    delete ptr;
  }
  static void Define(napi_env env,
                     napi_value constructor,
                     napi_value prototype) {
    Set(env, prototype, "date", &Child::Date);
  }
};

}  // namespace ki

// Export the converted constructors to JavaScript.
napi_value Init(napi_env env, napi_value exports) {
  ki::Set(env, exports,
          "Parent", ki::Class<Parent>(),
          "Child", ki::Class<Child>());
  return nullptr;
}

NAPI_MODULE(NODE_GYP_MODULE_NAME, Init);

Contributing

For new features, it is recommended to start an issue first before creating a pull request.

Generally I would encourage forking if you would like to add a feature that needs over a thousand lines, because I don't really have much time maintaining this project. But bug reports are very welcomed.