server.js

require("dotenv").config();
const path = require("path");
const express = require("express");
const app = express();

app.use(express.static(path.join(__dirname, "public")));

// -----------------------------  HANDLEBARS  -----------------------------
const exphbs = require("express-handlebars");
app.engine("handlebars", exphbs());
app.set("view engine", "handlebars");

// -------------------------  EXPRESS MIDDLEWARE  -------------------------
const logger = require("morgan");
const cookieParser = require("cookie-parser");
app.use(logger("dev"));
app.use(express.json());
app.use(express.urlencoded({ extended: false }));
app.use(cookieParser());

// --------------------------------  CORS  --------------------------------
// necessary for development using localhost
// allow cookies to be set by browser
// frontend API calls need to set "credentials: include"
const cors = require("cors");
if (process.env.NODE_ENV !== "production") {
  app.use(
    cors({
      origin: "http://localhost:3000",
      credentials: true,
    })
  );
}

// -------------------------------  MONGODB  ------------------------------

const mongoose = require("mongoose");
const MONGODB_URI = process.env.MONGODB_URI;
const db = require("./models")(mongoose);

try {
  mongoose.connect(MONGODB_URI, {
    useNewUrlParser: true,
    useFindAndModify: false,
    useCreateIndex: true,
    useUnifiedTopology: true,
  });
} catch (error) {
  throw error;
}

// ------------------------------  PASSPORT  ------------------------------
const passport = require("passport");
const localStrategy = require("passport-local").Strategy;
const jwt = require("jsonwebtoken");
const passportJWT = require("passport-jwt");
const bcrypt = require("bcrypt");
const validate = require("validate.js");
const constraints = require("./config/constraints");

require("./config/passport")(
  db,
  bcrypt,
  passport,
  localStrategy,
  passportJWT,
  validate,
  constraints
);

app.use(passport.initialize());

// ----------------------------  MOUNT ROUTER  ----------------------------
// ------ define sub-routers ------

const tokens = require("./utils/tokens");
const apiRouter = require("./routes/api")(express.Router(), passport, jwt, db);

const authRouter = require("./routes/auth")(
  express.Router(),
  passport,
  db,
  jwt,
  tokens
);

const renderRouter = require("./routes/render")(
  express.Router(),
  passport,
  db,
  jwt,
  tokens
);

// ------- mount sub-routers ------
app.use("/api", apiRouter);
app.use("/auth", authRouter);
app.use("/", renderRouter);

// ---------------------------  ERROR HANDLING  ---------------------------
const createError = require("http-errors");
// catch 404 and forward to error handler
app.use(function (req, res, next) {
  next(createError(404));
});

// error handler
app.use(function (err, req, res, next) {
  // set locals, only providing error in development
  res.locals.message = err.message;
  res.locals.error = req.app.get("env") === "development" ? err : {};

  // render the error page
  res.status(err.status || 500);
  res.render("error");
});

// ----------------------------  START SERVER  ----------------------------
const PORT = process.env.PORT;
app.listen(PORT, () => {
  console.log(`API Server started on port ${PORT}!`);
});

module.exports = app;