Real-time data with D3

Question

I was wondering if I could use the D3 library with real-time data my server would be sending via websockets. I can\'t see any documentation or examples that demonstrate this. My

Answer 1

I haven't used websockets with D3 (yet) but it looks like you're expecting d3.json to be a JSON parser. It's not - it's an AJAX loader that delegates to JSON.parse for parsing. So you probably want something like:

var ws = new WebSocket("ws://localhost:8888/ma");

var data = [];

ws.onmessage = function(evt) {
    // append new data from the socket
    data.push(JSON.parse(evt.data));
    update();
};

// now use the standard join pattern to deal with updates
function update() {
    var chunk = d3.selectAll('p')
        .data(data);

    // entry might be all you need, if you're always appending
    chunk.enter().append('p')
        .text(function(d) { return d; });

}