generator-oxy-gen/generators/app/templates/src/modules/rustWorker.js

Yeoman generator for Electron app with React and Rust (WASM).

// ------------------------
// Web worker file for running fibonacci
// recursive function written in Rust (WASM)
// ------------------------
export default function RustFibWebWorker(args) {
  // "main" function for communicating with the web worker
  this.onmessage = (e) => { // eslint-disable-line no-unused-vars
    // get the fibonacci seed number from user and path to WASM file
    const { seed, path } = e.data;

    if(this.fibonacci) {
      callFib();
    } else {
      // if we dont have the WebAssembly loaded, load it in!
      fetch(path)
        .then(response => response.arrayBuffer())
        .then(bytes => WebAssembly.instantiate(bytes, {imports: {}}))
        .then(results => {
          // bind rust WASM function to js function
          const { fibonacci } = results.instance.exports;
          // bind that function to `this` so we can use it later
          this.fibonacci = fibonacci;

          callFib();
        });
    }

    function callFib() {
      let sum;
      // time the fibonacci function
      let time = timedFunction(() => {
        sum = this.fibonacci(seed);
      });

      postMessage({ time, sum });
    }
  };

  const timedFunction = (func) => {
    var t0 = performance.now();
    func();
    var t1 = performance.now();

    return (t1 - t0);
  }
}