data binding in react + signalR - signalr

Question

I have a strategy question.
I want to change data in my website using signalR and display changed data using react. My question would be: How to perform data binding between signalR and react?
My first clue is the following:
signalR:
chat.client.addMessage = function (name, message) {
chatHistory.push({ Author: name, Text: message }); //here I change global variable chatHistory
};
react:
var CommentList = React.createClass({some class here});
var CommentBox = React.createClass({
componentRefresh: function () {
this.setState({ data: chatHistory });
},
getInitialState: function () {
return { data: chatHistory };
},
componentDidMount: function () {
this.componentRefresh();
setInterval(this.componentRefresh, this.props.interval);
},
render: function () {
return (
React.DOM.div(null,
CommentList({ data: this.state.data })
)
);
}
});
React.renderComponent(
CommentBox({ interval: 2000 }),
document.getElementById('content')
);
in react commentBox component I feed global chatHistory and ask for a new value every 2 seconds.
Is there more elegant way of doing it?
and how to avoid redrawing of CommentBox if chatHistory variable wasn't changed?

Answer 1

Your approach of maintaining state in CommentBox is fine. As your component base grows, it might become complicated to maintain self-updating components though. I recommend investigating the Flux architecture the React team designed and their Todo MVC Flux example in particular.
You could implement shouldComponentUpdate to prevent React from re-rendering the CommentBox if you know state hasn't changed. Also, you should keep a reference to the interval so you can clear it when the CommentBox is unmounted otherwise it will go on polling after the component is removed.
var CommentBox = React.createClass({
...
componentDidMount: function() {
this.componentRefresh();
this._interval = setInterval(this.componentRefresh, this.props.interval);
},
componentWillUnmount: function() {
clearInterval(this._interval);
this._interval = null;
},
shouldComponentUpdate: function(nextProps, nextState) {
// Do a deep comparison of `chatHistory`. For example, use
// Underscore's `isEqual` function.
return !_.isEqual(this.state.chatHistory, nextState.chatHistory);
},
...
});