server.js

const express = require("express");

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

const app = express();

// Serve static content for the app from the "public" directory in the application directory.
app.use(express.static("public"));

// Parse application body
app.use(express.urlencoded({ extended: true }));
app.use(express.json());

// Set Handlebars.
const ehb = require("express-handlebars");

app.engine("handlebars", ehb({ defaultLayout: "main" }));
app.set("view engine", "handlebars");

// Import routes and give the server access to them.
const routes = require("./controllers/book_controller.js");

app.use(routes);

// Start our server so that it can begin listening to client requests.
app.listen(PORT, function() {
  // Log (server-side) when our server has started
  console.log("Server listening on port " + PORT);
});