I'm building a simple web app that you can post phrases into. It does everything I want, except for showing what someone else appended to the site instantly. I know I could use socket.io for that but I'm wondering if I could achieve the same without using it so I can keep the site as simple as possible. Here's the code

//script.js file
fetch('https://server.jonaso1.repl.co/').then(response => response.json())
.then(data => {
   for (let i = 0; i < data.length; i  )
   prependPhrase(data[i]);
 }); //this loads saved stuff on the page when you access it

form.onsubmit = (e) => { //this posts input values on server (I omitted var declarations)
  e.preventDefault();
  var data = {
  [input.name1]:input1.value,
  [input2.name]:input2.value,
  [input3.name]:input3.value,
  };

  prependPhrase(data);

  fetch('https://server.jonaso1.repl.co/frases', {
    method: "POST",
    body: JSON.stringify(data),
    headers: {"Content-type": "application/json"}
    })
  };

function prependPhrase(data) {//just the function that puts the text on site
  const p = document.createElement('p');
  const span = document.createElement('span');
  p.setAttribute('class', 'p');
  container.prepend(p);
  p.append(`${data.user} enviou : `)
  p.append(span);
  span.append(`${data.frasefavorita}`)
  p.append(` - ${data.autor}`)
}

//server.js file
mongoose.connect(mongoDB).then(() => console.log('database conectada')).catch((err) => console.log(err));

app.use(cors());
app.use(express.urlencoded({extended:true}));
app.use(express.json());


app.get('/', (req, res) => {
  phrase.find().then(result => {//this responds to get reqs with mongodb
    res.send(JSON.stringify(result))
    })
  });

app.post('/frases', (req, res) => { //this saves more phrases in mongodb
  const frase = new phrase(req.body);
  frase.save().then(() => console.log('frase salva'));  
  });

app.listen(3000, () => {
console.log('listening on 3000')});

CodePudding user response：

I think you are searching for long polling. Here is a good explanation with an example https://javascript.info/long-polling

Here is an comparison of polling, sockets and sse https://codeburst.io/polling-vs-sse-vs-websocket-how-to-choose-the-right-one-1859e4e13bd9