server.ts

import path from "path";
import express from "express";
import { createRequestHandler } from "@remix-run/express";

const app = express();

app.use((req, res, next) => {
  // helpful headers:
  res.set("Strict-Transport-Security", `max-age=${60 * 60 * 24 * 365 * 100}`);

  // /clean-urls/ -> /clean-urls
  if (req.path.endsWith("/") && req.path.length > 1) {
    const query = req.url.slice(req.path.length);
    const safepath = req.path.slice(0, -1).replace(/\/+/g, "/");
    res.redirect(301, safepath + query);
    return;
  }
  next();
});

// http://expressjs.com/en/advanced/best-practice-security.html#at-a-minimum-disable-x-powered-by-header
app.disable("x-powered-by");

// Remix fingerprints its assets so we can cache forever.
app.use(
  "/build",
  // @ts-ignore
  express.static("public/build", { immutable: true, maxAge: "1y" })
);

// Everything else (like favicon.ico) is cached for an hour. You may want to be
// more aggressive with this caching.
app.use(express.static("public", { maxAge: "1h" }));

const BUILD_DIR = path.join(process.cwd(), "build");

app.all("*", createRequestHandler({ build: require(BUILD_DIR) }));

const port = process.env.PORT || 3000;

app.listen(port, () => {
  // require the built app so we're ready when the first request comes in
  require(BUILD_DIR);
  console.log(`✅ app ready: http://localhost:${port}`);
});