How I got into Angular.JS

When I had a few days off over last year’s Christmas holidays, I really caught on to the whole Bitcoin hype that was going on during that time. I spent hours watching the markets and trying to figure out how I could make a few bucks on the side with this interesting thing. Now what has that to do with AngularJS? Now that I finally had the time to write another blog post, I will try to fill you in. When I had a few days off over last year’s Christmas holidays, I really caught on to the whole Bitcoin hype that was going on during that time. I spent hours watching the markets and trying to figure out how I could make a few bucks on the side with this interesting thing. Now what has that to do with AngularJS? Now that I finally had the time to write another blog post, I will try to fill you in.

The first thing I figured out was that it seemed to be a really unstable market and that the price could climb or drop a few percent over the curse of an hour. So I wanted some kind of automated help to keep track of the current price. That was when I started to play around with the market API of btc-e.com. Everything was very straightforward and so I quickly had a script running in Node.js that kept informing me of bigger jumps in the price.

Now a few lines of console output accompanied by an email notification was not really appealing so I decided to build a web application on top of the Node.js script. I used express to build the application, which is really easy because it basically does everything for you. You just have to concentrate on your business logic. This enabled me to quickly put a page together, that would display the current price and would update that price every second using websockets.

The web developer in me was not really satisfied with a plain text page that just displays a few lines in a browser so I wanted more and this is where the fun with AngularJS started. I had a look at a few tutorials and started to code away…

As many other developers I came from a jQuery background and so the first thing I did was to write a jQuery plugin to visualize the data received by the websocket in a canvas using a candle stick graph.

I then used the ui-router module of angular to switch between different currency pairs like USD/BTC, USD/LTC, BTC/LTC and so on. This looked pretty good to me and I could keep track of the current rates in a nice graph and by that time I was absolutely hooked. New Ideas just kept flowing in and I spent almost every night in front of the screen figuring out how to lay out my ideas in Angular. So I wrapped the jQuery plugin in an angular directive and used modified it a bit so I could use angular’s data binding to feed it new/updated data from the websocket.

When I read up more about stock markets and financial mathematics, I came across some functions that could give some informative indicators on currency graphs. I quickly implemented a few of these functions and added them to my graph. The graph now looked somewhat like the final product.

Spaking a whole new firework of ideas in my mind, these indicators quickly led to me trying to implement a prediction algorithm. Miserably failing at predicting such a highly fluctual market, I found that I could still use those indicators to programmatically analyze the current market situation and issue buy and sell commands according to their signals.

I was so hooked by the ease of how things can be done in JavaScript that I wanted to enable anyone visiting my portal to play around with those indicators and write their own algorithm to issue buy and sell commands. I thought “Who knows, maybe someone smarter than me will figure out a way how to not only analyze but also predict the markets…”. Letting other users upload JavaScript to my server where it would be executed sounded like a very scary idea to me and I also did not want to analyze and approve every piece of code that someone will write, so I figured it would be best to just execute the algorithm in the browser.

I hooked up the famous ace online code editor and created two methods to test one’s algorithm. One against past market data and one on the live data the will be received by the websocket. This enables the developer to tweak and twiddle until the algorithm works as he intended it.

Constantly astonishing me with its ease of coding and all the features that come out of the box, AngularJS was the perfect choice for me and created a whole new ecosystem of web development for me.

You can see the final project running on www.cointelligence.net