node-bindgen

Easy way to write native Node.js module using idiomatic rust.

Example

```rust

use nodebindgen::derive::nodebindgen;

/// generate nodejs sum function

[node_bindgen]

fn sum(first: i32, second: i32) -> i32 {
first + second }

```

Import as Node.js module!

```js let addon = require('./dylib');

addon.sum(1,2) 3 ```

N-API

This crates utilizes Node N-API.

Build

Use nj-cli to generate native module. First install:

cargo install nj-cli

Build command to generate module directory.

nj-cli build

This will generates ".dylib" folder.

More examples

Callback

Use rust closure to invoke JS callback

```rust

[node_bindgen]

fn hello

let msg = format!("argument is: {}", first);

second(msg);

} ```

from node:

```js let addon = require('./dylib');

addon.hello(2,function(msg){ assert.equal(msg,"argument is: 2"); console.log(msg); // print out argument is 2 });

```

Async functions

Async rust function will return as promise.

```rust

use std::time::Duration; use flvfuturecore::sleep; use nodebindgen::derive::nodebindgen;

[node_bindgen]

async fn hello(arg: f64) -> f64 { println!("sleeping"); sleep(Duration::from_secs(1)).await; println!("woke and adding 10.0"); arg + 10.0 } ```

```js let addon = require('./dylib');

addon.hello(5).then((val) => { console.log("future value is{}",val); });

```

JavaScript class

JavaScript class can be implemented easily.

```rust

struct MyClass { val: f64, }

[node_bindgen]

impl MyClass {

#[node_bindgen(constructor)]
fn new(val: f64) -> Self {
    Self { val }
}

#[node_bindgen]
fn plus_one(&self) -> f64 {
    self.val + 1.0
}

#[node_bindgen(getter)]
fn value(&self) -> f64 {
    self.val
}

} ```

```js let addon = require('./dylib'); const assert = require('assert');

let obj = new addon.MyObject(10); assert.equal(obj.value,10,"verify value works"); assert.equal(obj.plusOne(),11); ```