What is the difference between channels and keys

Question

I'm developing an app with GoInstant, but the difference between keys and channels isn't very clear. When should I use keys vs channels?

Answer 1

Keys: As in key-value store, the Key object is the interface by which you manage and monitor a value in GoInstant. You should use them for CRUD (Create, Read, Update Delete).

key example:

// We create a new key using our room object
var movieName = yourRoom.key(‘movieName’);

// Prepare a handler for our `on` set event
function setHandler(value) {
    console.log(‘Movie has a new value’, value);
}

// Now when the value of our key is set, our handler will fire
movieName.on(‘set’, setHandler);

// Ready, `set`, GoInstant :)
movieName.set('World War Z', function(err) {
    if (!err) alert('Movie set successfully!')
}

---

Channels: Represent a full-duplex messaging interface. Imagine a multi-client pub/sub system. Channels do not store data, you can’t retrieve a message from a channel, you can only receive it. You should use it to propagate events between clients sharing a session.

channel example:

var mousePosChannel = yourRoom.channel('mousePosChannel');

// When the mouse moves, broadcast the mouse co-ordinates in our channel
$(window).on('mousemove', function(event) {
  mousePosChannel.message({
    posX: event.pageX,
    posY: event.pageY
  });
});

// Every client in this session can listen for changes to
// any users mouse location
mousePosChannel.on('message', function(msg) {
  console.log('A user in this room has moved there mouse too', msg.posX, msg.posY);
})

You can find the official docs here:

Key: https://developers.goinstant.net/v1/key/index.html

Channel: https://developers.goinstant.net/v1/channel/index.html