Building a Countdown Timer With Socket.io Pt. 3

Today’s the day we wrap up our countdown timer and deploy it to Heroku. But before we launch this puppy we need to clean house a little and spice up the visual appeal.

Refactoring the Stopwatch

While the Stopwatch from our last post worked OK there are a spots that can be improved. For starters I’d like to separate the formatting of the time from the onTick method. Mainly because I want to be able to pull the current time out whenever someone hits reset or a new connection is made. Here’s how I updated Stopwatch to accomodate these changes:

modles/stopwatch.js
var util    = require('util'),
    events  = require('events')
    _       = require('underscore');

// ---------------------------------------------
// Constructor
// ---------------------------------------------
function Stopwatch() {
    if(false === (this instanceof Stopwatch)) {
        return new Stopwatch();
    }

    this.hour = 3600000;
    this.minute = 60000;
    this.second = 1000;
    this.time = this.hour;
    this.interval = undefined;

    events.EventEmitter.call(this);

    // Use Underscore to bind all of our methods
    // to the proper context
    _.bindAll(this);
};

// ---------------------------------------------
// Inherit from EventEmitter
// ---------------------------------------------
util.inherits(Stopwatch, events.EventEmitter);

// ---------------------------------------------
// Methods
// ---------------------------------------------
Stopwatch.prototype.start = function() {
    if (this.interval) {
        return;
    }

    console.log('Starting Stopwatch!');
    // note the use of _.bindAll in the constructor
    // with bindAll we can pass one of our methods to
    // setInterval and have it called with the proper 'this' value
    this.interval = setInterval(this.onTick, this.second);
    this.emit('start:stopwatch');
};

Stopwatch.prototype.stop = function() {
    console.log('Stopping Stopwatch!');
    if (this.interval) {
        clearInterval(this.interval);
        this.interval = undefined;
        this.emit('stop:stopwatch');
    }
};

Stopwatch.prototype.reset = function() {
    console.log('Resetting Stopwatch!');
    this.time = this.hour;
    this.emit('reset:stopwatch', this.formatTime(this.time));
};

Stopwatch.prototype.onTick = function() {
    this.time -= this.second;

    var formattedTime = this.formatTime(this.time);
    this.emit('tick:stopwatch', formattedTime);

    if (this.time === 0) {
        this.stop();
    }
};

Stopwatch.prototype.formatTime = function(time) {
    var remainder = time,
        numHours,
        numMinutes,
        numSeconds,
        output = "";

    numHours = String(parseInt(remainder / this.hour, 10));
    remainder -= this.hour * numHours;

    numMinutes = String(parseInt(remainder / this.minute, 10));
    remainder -= this.minute * numMinutes;

    numSeconds = String(parseInt(remainder / this.second, 10));

    output = _.map([numHours, numMinutes, numSeconds], function(str) {
        if (str.length === 1) {
            str = "0" + str;
        }
        return str;
    }).join(":");

    return output;
};

Stopwatch.prototype.getTime = function() {
    return this.formatTime(this.time);
};

// ---------------------------------------------
// Export
// ---------------------------------------------
module.exports = Stopwatch;

I also namespaced the events so they would be easier to read when mixed in with the socket.io events. During the refactoring I noticed there were a lot of actors listening to, emitting or calling something like start. I’m not sure if there are common socket.io namespacing patterns but I based what I did on Backbone events and I think it works out well enough.

Cleaning up app.js

These changes to Stopwatch also require us to update the app.js that uses it.

app.js
var stopwatch = new Stopwatch();
stopwatch.on('tick:stopwatch', function(time) {
  io.sockets.emit('time', { time: time });
});

stopwatch.on('reset:stopwatch', function(time) {
  io.sockets.emit('time', { time: time });
});

stopwatch.start();

io.sockets.on('connection', function (socket) {
  io.sockets.emit('time', { time: stopwatch.getTime() });

  socket.on('click:start', function () {
    stopwatch.start();
  });

  socket.on('click:stop', function () {
    stopwatch.stop();
  });

  socket.on('click:reset', function () {
    stopwatch.reset();
  });
});

I’ve made it so whenever a user resets or connects to the page they get the latest time. And of course whenever the stopwatch ticks they’ll get an update as well. I think it might also be nice if pressing start dispatched the latest time, I should probably add that… ;)

Tweaking the views

Lastly I’ve updated the view by adding some more buttons to correspond to the start/stop and reset methods. I’ve also wrapped everything in a container to make it easier to position:

views/index.ejs
<div id="wrapper">
    <div id="countdown"></div>
    <button id="start" class="thoughtbot">Start</button>
    <button id="stop" class="thoughtbot">Stop</button>
    <button id="reset" class="thoughtbot">Reset</button>
</div>
public/js/main.js
var socket = io.connect(window.location.hostname);

socket.on('time', function (data) {
    $('#countdown').html(data.time);
});

$('#start').click(function() {
    socket.emit('click:start');
});

$('#stop').click(function() {
    socket.emit('click:stop');
});

$('#reset').click(function() {
    socket.emit('click:reset');
});

Also notice that the socket events coming from the view have been namespaced as well.

Improving the type

Next up I want to enhance the type using one of Google’s webfonts. I chose a font called Black Ops One which seemed appropriately militaristic. Setting it up was as easy as adding one line to my layout.ejs

views/layout.ejs
<link href='http://fonts.googleapis.com/css?family=Black+Ops+One' rel='stylesheet' type='text/css'>

and my main.css file:

public/css/main.css
#countdown {
  font-family: 'Black Ops One', cursive;
  font-size: 90px;
}

Finally I chose to use some funky buttons from Chad Mazzola’s CSS3 Buttons project. I went with the Thoughtbot buttons since they were red and awesome. The styles are pretty long so I’m just going to post my entire main.css for you to see:

public/css/main.css
#wrapper {
  width: 475px;
  height: 171px;
  margin: 100px auto;
}

#countdown {
  font-family: 'Black Ops One', cursive;
  font-size: 90px;
}

button.thoughtbot {
  background-color: #ee432e;
  background-image: -webkit-gradient(linear, left top, left bottom, color-stop(0%, #ee432e), color-stop(50%, #c63929), color-stop(50%, #b51700), color-stop(100%, #891100));
  background-image: -webkit-linear-gradient(top, #ee432e 0%, #c63929 50%, #b51700 50%, #891100 100%);
  background-image: -moz-linear-gradient(top, #ee432e 0%, #c63929 50%, #b51700 50%, #891100 100%);
  background-image: -ms-linear-gradient(top, #ee432e 0%, #c63929 50%, #b51700 50%, #891100 100%);
  background-image: -o-linear-gradient(top, #ee432e 0%, #c63929 50%, #b51700 50%, #891100 100%);
  background-image: linear-gradient(top, #ee432e 0%, #c63929 50%, #b51700 50%, #891100 100%);
  border: 1px solid #951100;
  -webkit-border-radius: 5px;
  -moz-border-radius: 5px;
  border-radius: 5px;
  -webkit-box-shadow: inset 0px 0px 0px 1px rgba(255, 115, 100, 0.4), 0 1px 3px #333333;
  -moz-box-shadow: inset 0px 0px 0px 1px rgba(255, 115, 100, 0.4), 0 1px 3px #333333;
  box-shadow: inset 0px 0px 0px 1px rgba(255, 115, 100, 0.4), 0 1px 3px #333333;
  color: #fff;
  font: bold 20px "helvetica neue", helvetica, arial, sans-serif;
  line-height: 1;
  padding: 12px 0 14px 0;
  text-align: center;
  text-shadow: 0px -1px 1px rgba(0, 0, 0, 0.8);
  width: 150px;
}

button.thoughtbot:hover {
  background-color: #f37873;
  background-image: -webkit-gradient(linear, left top, left bottom, color-stop(0%, #f37873), color-stop(50%, #db504d), color-stop(50%, #cb0500), color-stop(100%, #a20601));
  background-image: -webkit-linear-gradient(top, #f37873 0%, #db504d 50%, #cb0500 50%, #a20601 100%);
  background-image: -moz-linear-gradient(top, #f37873 0%, #db504d 50%, #cb0500 50%, #a20601 100%);
  background-image: -ms-linear-gradient(top, #f37873 0%, #db504d 50%, #cb0500 50%, #a20601 100%);
  background-image: -o-linear-gradient(top, #f37873 0%, #db504d 50%, #cb0500 50%, #a20601 100%);
  background-image: linear-gradient(top, #f37873 0%, #db504d 50%, #cb0500 50%, #a20601 100%);
  cursor: pointer;
}

button.thoughtbot:active {
  background-color: #d43c28;
  background-image: -webkit-gradient(linear, left top, left bottom, color-stop(0%, #d43c28), color-stop(50%, #ad3224), color-stop(50%, #9c1500), color-stop(100%, #700d00));
  background-image: -webkit-linear-gradient(top, #d43c28 0%, #ad3224 50%, #9c1500 50%, #700d00 100%);
  background-image: -moz-linear-gradient(top, #d43c28 0%, #ad3224 50%, #9c1500 50%, #700d00 100%);
  background-image: -ms-linear-gradient(top, #d43c28 0%, #ad3224 50%, #9c1500 50%, #700d00 100%);
  background-image: -o-linear-gradient(top, #d43c28 0%, #ad3224 50%, #9c1500 50%, #700d00 100%);
  background-image: linear-gradient(top, #d43c28 0%, #ad3224 50%, #9c1500 50%, #700d00 100%);
  -webkit-box-shadow: inset 0px 0px 0px 1px rgba(255, 115, 100, 0.4);
  -moz-box-shadow: inset 0px 0px 0px 1px rgba(255, 115, 100, 0.4);
  box-shadow: inset 0px 0px 0px 1px rgba(255, 115, 100, 0.4);
}

SWEEEEEEET! I’ll go ahead and host it on Heroku but first I have to find out what the cost of leaving Node.js/Socket.io running indefinitely would be. Till then you should be able to get a local version of all this working or just clone the Github repo and now you too can have your very own Defcon stopwatch. enjoy! - Rob

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