N-API

它独立于底层 JavaScript 运行时（例如 V8），并作为 Node.js 自身的一部分进行维护。 此 API 将在 Node.js 的各个版本中保持稳定的应用程序二进制接口 (ABI)。 它旨在将插件与底层 JavaScript 引擎中的更改隔离开来，并允许为一个版本编译的模块无需重新编译即可在更高版本的 Node.js 上运行。 插件是使用本文档中概述的相同方法/工具（node-gyp 等）构建/打包的。唯一的区别是原生代码使用的 API 集。

所有其他指令保持不变。

// 
#include <node_api.h>

namespace demo {

napi_value Method(napi_env env, napi_callback_info args) {
  napi_value greeting;
  napi_status status;

  status = napi_create_string_utf8(env, "world", NAPI_AUTO_LENGTH, &greeting);
  if (status != napi_ok) return nullptr;
  return greeting;
}

napi_value init(napi_env env, napi_value exports) {
  napi_status status;
  napi_value fn;

  status = napi_create_function(env, nullptr, 0, Method, nullptr, &fn);
  if (status != napi_ok) return nullptr;

  status = napi_set_named_property(env, exports, "hello", fn);
  if (status != napi_ok) return nullptr;
  return exports;
}

NAPI_MODULE(NODE_GYP_MODULE_NAME, init)

}  // namespace demo

N-API is an API for building native addons. It is independent from the underlying JavaScript runtime (e.g. V8) and is maintained as part of Node.js itself. This API will be Application Binary Interface (ABI) stable across versions of Node.js. It is intended to insulate addons from changes in the underlying JavaScript engine and allow modules compiled for one version to run on later versions of Node.js without recompilation. Addons are built/packaged with the same approach/tools outlined in this document (node-gyp, etc.). The only difference is the set of APIs that are used by the native code. Instead of using the V8 or Native Abstractions for Node.js APIs, the functions available in the N-API are used.

Creating and maintaining an addon that benefits from the ABI stability provided by N-API carries with it certain implementation considerations.

To use N-API in the above "Hello world" example, replace the content of hello.cc with the following. All other instructions remain the same.

// hello.cc using N-API
#include <node_api.h>

namespace demo {

napi_value Method(napi_env env, napi_callback_info args) {
  napi_value greeting;
  napi_status status;

  status = napi_create_string_utf8(env, "world", NAPI_AUTO_LENGTH, &greeting);
  if (status != napi_ok) return nullptr;
  return greeting;
}

napi_value init(napi_env env, napi_value exports) {
  napi_status status;
  napi_value fn;

  status = napi_create_function(env, nullptr, 0, Method, nullptr, &fn);
  if (status != napi_ok) return nullptr;

  status = napi_set_named_property(env, exports, "hello", fn);
  if (status != napi_ok) return nullptr;
  return exports;
}

NAPI_MODULE(NODE_GYP_MODULE_NAME, init)

}  // namespace demo

The functions available and how to use them are documented in C/C++ addons with N-API.