index.js

//DEPENDENCIES
// These are modules required by other modules for them to work
const moment = require("moment");
const express = require("express");
const mongoose = require("mongoose");
const homeRoutes = require("./routes/homeRoutes");
const contactRoutes = require("./routes/contactRoutes");
const expenseTrackingRoutes = require("./routes/expenseTrackingRoutes");
const registerVehicleRoutes = require("./routes/registerVehicleRoutes");
const registerWasherRoutes = require("./routes/registerWasherRoutes");
const registerManagerRoutes = require("./routes/registerManagerRoutes");
const reportRoutes = require("./routes/reportRoutes");
const authRoutes = require("./routes/authRoutes");
const Manager = require("./models/Manager");
const passport = require("passport");
const expressSession = require("express-session")({
  secret: "secret",
  resave: false,
  saveUninitialized: false,
});

require("dotenv").config();

//INSTANTIATIONS- Are statements to create an object
//We create a new Express app using the express function and assigning it to an app variable.
//Express is a nodejs framework for writing web apps
const app = express();

//mongoose connection
mongoose.connect(process.env.DATABASE, {
  useNewUrlParser: true,
  useUnifiedTopology: true,
});
mongoose.connection
  .on("open", () => {
    console.log("Mongoose connection open");
  })
  .on("error", (err) => {
    console.log(`Connection error: ${err.message}`);
  });

//CONFIGURATIONS OR SETTINGS- Are custom application based settings
//We configure app.js to use Pug as a layout engine and to look for templates inside the views folder:
app.locals.moment = moment;
app.set("view engine", "pug");
app.set("views", "./views");

//MIDDLEWARE- These are used to determine the flow of the response cycle
app.use(express.urlencoded({ extended: true }));

// css access
app.use(express.static("public"));

app.use(expressSession);
app.use(passport.initialize());
app.use(passport.session());

passport.use(Manager.createStrategy());
passport.serializeUser(Manager.serializeUser());
passport.deserializeUser(Manager.deserializeUser());

// this custom middleware checks if the person trying to access the site has a session or not
var loginChecker = function (req, res, next) {
  if (req.path != "/login" && req.path != "/contact" && !req.session.user) {
    res.redirect("/login");
  }
  next();
};
app.use(loginChecker);

// ROUTES
//We tell the app that, whenever it receives a request from forward slash anything, it should use the routes file.
app.use("/", homeRoutes);
app.use("/contact", contactRoutes);
app.use("/expensetracking", expenseTrackingRoutes);
app.use("/vehicleregistration", registerVehicleRoutes);
app.use("/washerregistration", registerWasherRoutes);
app.use("/report", reportRoutes);
app.use("/", authRoutes);
app.use("/registermanager", registerManagerRoutes);

//The code below is use to handle non existing routes.
app.get("*", (req, res) => {
  res.status(404).send("This is an invalid URL, please try another");
});

//Binds and listens for connections on the specified host and port.In my case port 2000
app.listen(2000, () => {
  console.log("I am listening in on port 2000");
});