Proper use of layer.invalidate() in Carto.js

Question

According to the Carto.js documentation, layer.invalidate():

"Refreshes the data. If the data has been changed in the CARTO server those changes will be displayed. Nothing happens otherwise. Every time a parameter is changed in a sublayer, the layer is refreshed automatically, so there’s no need to call this method manually."

However, I'm wondering if I'm not using invalidate properly. I have changed data in the CARTO server (ie. table values), however calling layer.invalidate() doesn't refresh my map.

cartodb.createLayer(map, {
    user_name: 'user_name',
    type: 'cartodb',
    sublayers: [
        //Baselayer
        {
        type: "http",
        urlTemplate: 'http://{s}.basemaps.cartocdn.com/light_nolabels/{z}/{x}/{y}.png',
        subdomains: [ "a", "b", "c" ]
        },

        //Projects
        {
        sql: "SELECT * FROM ab",
        cartocss: '#ab {marker-fill: #15B14D;}',
        interactivity: ['name', 'description', 'source', 'contact', 'category'],
        },

        //Labels
        {
        type: "http",
        urlTemplate: 'http://{s}.basemaps.cartocdn.com/light_only_labels/{z}/{x}/{y}.png',
        subdomains: [ "a", "b", "c" ]
        },
        ],
    })
.addTo(map)
.done(function (layer){
    cartodb.vis.Vis.addInfowindow(map, layer, ['name', 'description', 'source', 'contact', 'category'],{
        infowindowTemplate: $('#infowindow_template').html(),
        templateType: 'mustache'});
    layer.invalidate();
    });

Answer 1

You need to run the invalidate method within a setTimeout or setInterval functions, as shown in this working example:

setInterval(function(){ 
layer.invalidate(); 
console.log("Update!")
}, 5000);

Because if you place it outside, it will invalidate at the same time you are rendering the map and the result would be the same.