server.js

const express = require('express');
const cors = require('cors');
const bodyParser = require('body-parser');
const MongoClient = require('mongodb').MongoClient;

const PORT = 5000;
const MONGO_URL = 'mongodb://localhost:27017/';

const app = express();

app.use(cors('*'));
app.use(bodyParser.urlencoded({ extended: true }));
app.use(bodyParser.json());

app.use(express.static('./build'));

MongoClient.connect(MONGO_URL, function(err, client) {
  if (err) {
    console.log(err);
    return;
  }

  const db = client.db('european-capitals-game');

  app.get('/api/countries', function(req, res) {
    db
      .collection('countries')
      .find()
      .toArray(function(err, result) {
        if (err) {
          console.log(err);
          res.status(500);
          res.send();
          return;
        }
        res.json(result);
      });
  });

  app.get('/api/countries/random', function(req, res) {
    db
      .collection('countries')
      .find({})
      .toArray(function(err, result) {
        if (err) {
          console.log(err);
          res.status(500);
          res.send();
          return;
        }

        const randomCountry = result[Math.floor(Math.random() * result.length)];

        res.json(randomCountry);
      });
  });

  app.post('/api/scores', function(req, res) {
    db.collection('scores').insert(req.body, function(err, result) {
      if (err) {
        console.log(err);
        res.status(500);
        res.send();
        return;
      }

      res.status(201);
      res.json(result.ops[0]);
    });
  });

  app.get('/api/scores', function(req, res) {
    db
      .collection('scores')
      .find({})
      .sort({score: -1})
      .toArray(function(err, result) {
        if (err) {
          console.log(err);
          res.status(500);
          res.send();
          return;
        }

        res.status(200).json(result);
      });
  });

  app.delete('/api/scores', function(req, res) {
  db.collection('scores').remove({}, function(err, result) {
    if (err) {
      console.log(err);
      res.status(500);
      res.send();
      return;
    }

    res.status(204);
    res.send();
  });
});

  console.log('Connected to DB');
  console.log('Starting server...');

  app.listen(PORT, function() {
    console.log(`Server started on ${PORT}`);
  });
});