server.js

const express = require('express');
const MongoClient = require('mongodb').MongoClient;
const uri = "mongodb+srv://nandit123:<password>@cluster0.nj3nz.mongodb.net/db1?retryWrites=true&w=majority";

const app = express();
app.use(express.json())

const port = process.env.PORT || 3001;

app.listen(port, function (err) {
  if (err) console.log(err);
  console.log('server listening on PORT', port);
});

app.get('/', (req, res) => {
  res.send('GET request called');
})

app.post('/addRating', (req, res) => {
  console.log('entered addRating with parameters: ', req.body);
  const client = new MongoClient(uri, { useNewUrlParser: true, useUnifiedTopology: true });
  async function run() {
    try {
      console.log('entered try block');
      await client.connect();
      console.log('connected correctly to the server');

      const db = client.db("db1");

      const col = db.collection("cl1");

      let ratingDocument = {
        userId: req.body.userId,
        url: req.body.url,
        rating: req.body.rating,
        type: 'rating'
      };

      // insert a single document, wait for promise  so we can read it back
      const p = await col.insertOne(ratingDocument);

      // find one document
      const myDoc = await col.findOne();

      // print to the console
      console.log('mydoc:', myDoc);
    } catch (e) {
      console.log('got an error:', e);
    } finally {
      await client.close();
    }
  }
  run();
  res.send('done')
})

app.post('/addReport', (req, res) => {
  console.log('entered addReport with parameters: ', req.body);
  const client = new MongoClient(uri, { useNewUrlParser: true, useUnifiedTopology: true });
  async function run() {
    try {
      console.log('entered try block');
      await client.connect();
      console.log('connected correctly to the server');

      const db = client.db("db1");

      const col = db.collection("cl1");

      let reportDocument = {
        userId: req.body.userId,
        url: req.body.url,
        reportReason: req.body.reportReason,
        reasonType: req.body.reasonType, // 1-5 for checkbox reason, 6 for manually written by the user
        type: "report"
      };

      // insert a single document, wait for promise  so we can read it back
      const p = await col.insertOne(reportDocument);

      // find one document
      const myDoc = await col.findOne();

      // print to the console
      console.log('mydoc:', myDoc);
    } catch (e) {
      console.log('got an error:', e);
    } finally {
      await client.close();
    }
  }
  run();
  res.send('done')
})


app.get('/getRating', (req, res) => {
  console.log('entered getRating with parameters: ', req.body);
  const client = new MongoClient(uri, { useNewUrlParser: true, useUnifiedTopology: true });
  async function run() {
    try {
      console.log('entered try block');
      await client.connect();
      console.log('connected correctly to the server');

      const db = client.db("db1");

      const col = db.collection("cl1");

      const query = { url: req.body.url };

      const options = {
        projection: { rating: 1 }
      }

      const cursor = await col.find(query, options);

      // print a message if no documents were found!
      if ((await cursor.count) === 0) {
        console.log('no documents found!');
        res.send({});
      }

      const ratingsArray = [];
      await cursor.forEach(function (item) {
        if (item.rating)
          ratingsArray.push(item.rating);
      });

      const totalRatings = ratingsArray.length;
      const averageRating = (ratingsArray.reduce((a, b) => a + b, 0)) / totalRatings;
      res.send({
        totalRatings: totalRatings,
        averageRating: averageRating
      })
    } catch (e) {
      console.log('got an error:', e);
      res.send('error:', e)
    } finally {
      await client.close();
    }
  }
  run();
})

app.post('/addUser', (req, res) => {
  console.log('entered addUser with parameters: ', req.body);
  const client = new MongoClient(uri, { useNewUrlParser: true, useUnifiedTopology: true });
  async function run() {
    try {
      console.log('entered try block');
      await client.connect();
      console.log('connected correctly to the server');

      const db = client.db("db1");

      const col = db.collection("user");

      let userDocument = {
        userId: req.body.userId,
        balance: 0,
        walletAddress: '',
        timeCreated: Date.now()
      };

      // insert a single document, wait for promise  so we can read it back
      const p = await col.insertOne(userDocument);

      // find one document
      const myDoc = await col.findOne();

      // print to the console
      console.log('mydoc:', myDoc);
    } catch (e) {
      console.log('got an error:', e);
    } finally {
      await client.close();
    }
  }
  run();
  res.send('done')
})

app.get('/getUser', (req, res) => {
  console.log('entered getRating with parameters: ', req.body);
  const client = new MongoClient(uri, { useNewUrlParser: true, useUnifiedTopology: true });
  async function run() {
    try {
      console.log('entered try block');
      await client.connect();
      console.log('connected correctly to the server');

      const db = client.db("db1");

      const col = db.collection("user");

      const query = { userId: req.body.userId };

      const user = await col.findOne(query);
      console.log('user recieved:', user);

      res.send({
        userId: user.userId,
        balance: user.balance,
        walletAddress: user.walletAddress,
        timeCreated: user.timeCreated
      })
    } catch (e) {
      console.log('got an error:', e);
      res.send('error:', e)
    } finally {
      await client.close();
    }
  }
  run();
})

console.log('restfulAPI started at port', port);