app.js

const express = require('express');
const app = express();
const morgan = require('morgan');
const bodyParser = require('body-parser');
const mongoose = require('mongoose');
const cors = require("cors");

const userRoutes = require('./api/routes/user');
const postRoutes = require('./api/routes/post');

mongoose.connect(
    'mongodb+srv://ilad:' +
    process.env.MONGO_ATLAS_PW +
    '@todo-app.tnrgb.mongodb.net/share-ur-code?retryWrites=true&w=majority',
    {
        useNewUrlParser: true,
        useUnifiedTopology: true
    }
);

mongoose.Promise = global.Promise;

app.use(morgan('dev'));
app.use(bodyParser.urlencoded({ extended: false }));
app.use(bodyParser.json());

app.use(cors());
app.use(function (req, res, next) {
    res.setHeader("Access-Control-Allow-Origin", "*");
    res.setHeader("Access-Control-Allow-Credentials", "true");
    res.setHeader(
        "Access-Control-Allow-Methods",
        "GET,HEAD,OPTIONS,POST,PUT,DELETE"
    );
    res.setHeader(
        "Access-Control-Allow-Headers",
        "Origin,Cache-Control,Accept,X-Access-Token ,X-Requested-With, Content-Type, Access-Control-Request-Method"
    );
    if (req.method === "OPTIONS") {
        return res.status(200).end();
    }
    next();
});

app.use('/user', userRoutes);
app.use('/post', postRoutes);

app.use((req, res, next) => {
    const error = new Error('Not found');
    error.status = 404;
    next(error);
});

app.use((error, req, res, next) => {
    res.status(error.status || 500);
    res.json({
        error: {
            message: error.message
        }
    });
});

module.exports = app;