server.js

const express = require("express");
const body_parser = require("body-parser");
const PORT = process.env.PORT || 4000;
const colors = require("colors");
// const IP = process.env.IP;
const app = express();
const methodOverride = require("method-override");
const mongoose = require("mongoose");
const Campgound = require("./models/campground");
const Comment = require("./models/comment");
const SeedDB = require("./seeds");
const passport = require("passport");
const LocalStrategy = require("passport-local");
const User = require("./models/user");
const flash = require("connect-flash");

//requiring routes
const campgroundRoutes = require("./routes/campgrounds");
const commentRoutes = require("./routes/comments");
const authRoutes = require("./routes/auth");

// ===================================
//        MONGOOSE CONFIGURATION
// ===================================

//mongoose.connect("mongodb://localhost/yelp_camp_for_restful_api_deployingToHeroku",{ useNewUrlParser: true ,useUnifiedTopology: true });

var url =
  process.env.DATABASEURL ||
  "mongodb://localhost/yelp_camp_for_restful_api_deployingToHeroku";

// mongoose.connect("mongodb+srv://saeedhassan:<PASSWORDHERE>@cluster0-ctusi.mongodb.net/yelpcamp?retryWrites=true&w=majority",{ useNewUrlParser: true ,useUnifiedTopology: true })

mongoose
  .connect(url, { useNewUrlParser: true, useUnifiedTopology: true })

  .then(() => {
    console.log(colors.bgGreen("server is connected successfully"));
  })
  .catch((err) => {
    console.log(colors.red("Error occurs in Mongoose :===>Connection", err));
  });

mongoose.connection.once("open", (err) => {
  if (err) {
    console.log("Error in MONGOOSE connection", err);
  } else {
    console.log(colors.bgBlue("mongoose is connected to nodejs successfully"));
  }
});
//mongodb+srv://saeedhassan:<PASSWORDHERE>@cluster0-ctusi.mongodb.net/test?retryWrites=true&w=majority

// ===================================
//       SEEDING
// ===================================
//SeedDB()        // we will call this when we remove all campgrounds from database otherwise we dont

// ===================================
//        EXPRESS-SESSION
// ===================================
app.use(
  require("express-session")({
    secret: "Hello Iam Saeed Hassan Solangi From Dadu, Sindh , Pakistan",
    resave: false,
    saveUninitialized: false,
  })
);

// ===================================
//        PASSPORT CONFIGURATION
// ===================================
app.use(passport.initialize());
app.use(passport.session());
passport.use(new LocalStrategy(User.authenticate())); //User.authenticate(comesFrompassportLocalMongooseplugn)
passport.serializeUser(User.serializeUser());
passport.deserializeUser(User.deserializeUser());

// ===================================
//       APP CONFIGURATION
// ===================================
app.use(express.static(__dirname + "/public"));
app.set("view engine", "ejs");
app.use(body_parser.urlencoded({ extended: true }));
app.use(methodOverride("_method"));

// ===================================
//        CONNECT-FLASH CONFIGURATION
// ===================================
app.use(flash());

app.use((req, res, next) => {
  res.locals.currentUser = req.user; // by res.locals , this will add currentUser to all the templates
  res.locals.error = req.flash("error");
  res.locals.success = req.flash("success");
  res.locals.info = req.flash("info");
  res.locals.primary = req.flash("primary");
  next();
});

// ===================================
//       MANAGING REQUIRING ROUTES
// ===================================
app.use("/campgrounds", campgroundRoutes);
app.use("/campgrounds/:id/comments", commentRoutes);
app.use("/", authRoutes);

app.listen(PORT, () =>
  console.log(colors.bgMagenta(`SERVER IS RUNNING ON THE PORT ${PORT}`))
);