WCS - Express 3 - POST data

const connection = require('./config');
const express = require("express");

const port = 3000;
const app = express();

connection.connect(err => {
  if(err){
    console.log('error connecting: ' + err.stack);
    return;
  }
  console.log('connected as id ' + connection.threadId);
})

app.use(express.json());

app.listen(port, () => {
  console.log(`Server listen on ${port}`);
});

app.get("/", (req, res) => {
  res.send("Welcome to my favourite movies list!");
});

app.get("/api/movies", (req, res) => {
  connection.query("SELECT * FROM movies", (err, results) => {
    if(err){
      res.status(500).send("error retrieving datas");
    }else{
      res.status(200).json(results);
    }
  })
});

app.get("/api/movies/:id", (req, res) => {
  connection.query(
    "SELECT * FROM movies WHERE id=?", 
    [req.params.id], 
    (err, results) => {
      if(err || results.length == 0){
        res.status(500).send("error retrieving datas");
      }else{
        res.status(200).json(results);
      }
  })
});

app.get("/api/search", (req, res) => {
  connection.query(
    `SELECT * FROM movies WHERE duration <= ${req.query.maxDuration}`,
    (err, results) => {
      if(err){
        res.status(500).send("error retrieving datas");
      }else{
        if(results.length > 0){
          res.status(200).json(results);
        }else{
          res.status(404).send("No results for this duration");
        }
      }
    })
});

app.post('/api/movies', (req, res) => {
  const {title, director, year, color, duration} = req.body;
  connection.query(
    "INSERT INTO movies (title, director, year, color, duration) VALUES(?,?,?,?,?)", 
    [title, director, year, color, duration], 
    (err, results) => {
      if(err){
        console.log(err);
        res.status(500).send("Error saving movie");
      }else{
        res.status(200).send("Successfully saved into database");
      }
    })
})

app.get("/users", (req, res) => {
  connection.query(
    "SELECT * FROM users",
    (err, results) => {
      if(err){
        res.sendStatus(500);
      }else{
        res.status(200).send(results);
      }
    })
});

app.post("/users", (req, res) => {
  const {firstname, lastname, email} = req.body;
  connection.query(
    "INSERT INTO users (firstname, lastname, email) VALUES(?,?,?)",
    [firstname, lastname, email],
    (err, results) => {
      if(err){
        console.log(err);
        res.status(500).send("Failed to save data");
      }else{
        res.status(200).send("User saved succesfully");
      }
    }
  )
})