wasm-builder.js

const { execSync } = require("child_process");
const fs = require("fs");
const Bundler = require("parcel-bundler");
const Path = require("path");
const chokidar = require("chokidar");
const dotenv = require("dotenv");
const app = require("express")();
const compression = require("compression");
dotenv.config();

const entryFiles = Path.join(__dirname, "index.html");

const buildType = process.env.NODE_ENV;

const options = {
  outDir: "./dist",
  outFile: "index.html",
  publicUrl: "/",
  watch: true,
  minify: buildType === "production",
};

const bundler = new Bundler(entryFiles, options);

chokidar
  .watch(["./crate/src", "./crate/Cargo.toml"])
  .on("change", async (event, path) => {
    console.log(
      `there are new changes in '${path}'. Start to rebuild rustwasm sources`
    );

    bundler.bundle();

    bundler.hmr.broadcast({
      type: "reload",
    });
  });

bundler.on("buildStart", () => {
  let prevtBuildFile = Path.join(__dirname, "./wasm_pack_cmd");
  if (process.platform === "win32") {
    prevtBuildFile = Path.join(__dirname, "./wasm_pack_cmd.bat");
  }

  console.log(`running: ${prevtBuildFile}`);
  execSync(`${prevtBuildFile} ${buildType === "production" ? "" : "--dev"}`, {
    stdio: "inherit",
  });
});

if (buildType === "production") {
  app.use(compression());
}

app.use(bundler.middleware());

app.listen(process.env.SERVER_ADDRESS || 1234, () => {
  console.log(
    `Yew app start in address: ${
      process.env.SERVER_ADDRESS || "http://localhost:1234"
    }`
  );
});