Tag: mobile application

HTTP2: the good, the bad and the ugly

I spent last few weeks investigating on HTTP2, the successor of HTTP1.1 and I’d like to share my findings and thoughts in this post.

Let’s start saying that if the question you have in mind at this point is: “Can I really use it today, not only for experiments but also in production?”
My answer would be: “YES, you can!”

First of all, I’d like to share with you the browsers implementation status for this protocol

screen-shot-2016-09-06-at-23-00-23

As you can see from the screenshot taken from caniuse.com it’s definitely well supported on the latest version of the major browsers with some caveats obviously.

If you are not convinced yet, please check this website with one of the browsers that currently supports HTTP2 and look how fast to load is!
I’d suggest to install the HTTP2 indicator Chrome extension to discover how many web apps or online services are using this protocol:

screen-shot-2016-09-07-at-21-41-09

Not yet convince?! OK let’s move to a deeper analysis then!

HTTP2 is a binary protocol with a multiplexing requests method implemented, that means all the browser requests will be handled asynchronously.

This massive change will increase drastically the performance of your application.
Considering at the moment a browser can download simultaneously a maximum of 5 resources per domain (let’s avoid talking about “resource sharding” for now), with HTTP2 we will be able to request all the resources and render them when the browser will accomplish their download, check this demo made with Go Lang for a proper comparison between the 2 protocols and check also the Network panel in the Chrome Dev Tools or Firefox dev tools in order to understand how the 2 protocols differ.

The Good

HTTP2 has really few rules in order to be implemented:

  • it works ONLY with https protocol (therefore you need a valid SSL certificate)
  • it’s backward compatible, so if a browser or a device where your application is running, don’t support HTTP2 it will fall back to HTTP1.1
  • it comes with great performance improvements out-of-the-box
  • it doesn’t require to do anything on the client side but on the server side for a basic implementation
  • few new interesting features will allow to speed up the load of your web project in a way that is not even imaginable with HTTP1.1 implementation

Despite the short list, HTTP2 is bringing a substantial change to the internet ecosystem.
One of my favourite feature is the server PUSH where a server can pass a link header specifying what the browser should download in advance before starting to parse entirely the HTML document.
In this case, we can educate the browser to download several resources like images, css or even javascript files before the engine recognise them inside the DOM, providing a better user experience to our web apps and/or games.

The Bad

There is still plenty of works to do in order to have a great penetration of this protocol, few specs are still on going (read the next paragraph: the ugly) and probably it will take quite few months before we will see a lot of services moving to this new protocol.

A part from the high level overview of the downsides, let’s look what will change on the technical side.

Considering that HTTP2 is not restrict on the amount of requests a browser is doing in order to download resources few techniques for optimising our websites will need to be reviewed or even removed from our pipeline.
Delivering all the application inside a unique javascript file won’t have any benefit with HTTP2, so we need to move our logic downloading only what we need when we need it.
Knowing that downloading large files won’t be a problem we could use sprites instead of several small images to handle the icons of our website.
Probably the different tools like Grunt, Gulp or Webpack will need to review their strategies or update their plugin in order to provide real value to this new project pipeline.

The Ugly

Google Chrome protocol implementation!
Chrome is my favorite browser and I use it extensively, in particular, when I need to debug a specific script or I need to gather metrics from a specific behavior of a web app.
At the moment it’s the only browser that requires HTTP2 server negotiation via ALPN (Application-Layer Protocol Negotiation) that basically is an extension allowing the application layer to negotiate which protocol will be used within the TLS connection.

Considering that OpenSSL integrates ALPN only from version 1.0.2, we won’t be able to enable HTTP2 protocol support for Chrome (from build 51 and above) if we don’t configure our server correctly.
For instance, on Linux OS, only Ubuntu from version 16.04 has that OpenSSL version installed by default, for all the other major Linux version you will either install the newer version manually or you’ll need to wait for the next major OS release.

I’d suggest reading carefully the article that describes this “issue” on ngnix blog before you start to configure your server for Chrome.

Wrap up

HTTP2 is not perfect and probably is not supported as it should be but, definitely, could improve (drastically in certain cases) your web project performance.
A lot of “big players” are already using HTTP2 protocols in production (Instagram, Twitter or Facebook for instance) and the results are remarkable.

Why not starting catching up with the future today?

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Adobe AIR 3.8 introduces Socket Server on Android and iOS

Hi All,

after long time I’m back for all the developers are working with the Flash Platform right now!
Sorry for that but it was a really intensive period for me with the organization of “Having fun with Adobe AIR” so I haven’t a lot of time to share with you my new experiments.
Yesterday Adobe MAX is finished with a lots of design news, great and inspire case histories for designers and a lot of amusement during the Sneak Peek where they have shown the real power of Adobe labs with tons of really cool features that we could see in next releases of Adobe’s softwares.
For a developer perspective there weren’t big announces so, as usual, we can do it by ourselves…. and here we are!

During last few days Adobe release the Adobe AIR 3.8 and Flash Player 11.8, both in BETA but you can download and start to play with them.
When Adobe releases a new AIR SDK I always take a look to the release notes to see the new features of my favorite platform, this time I’m glad to announce that they add the opportunity to create TCP/IP and UDP socket server directly on iOS and Android.
This is a very cool feature because you can really create amazing things in particular for applications and games, for example local multiplayer, chat and so on.
I worked a lots with sockets during last years in several projects and my big concern was that I can’t create a socket server on smartphone and tablet with AIR, I could do that only with native code but I was pretty sure to see this feature will be implemented in next releases of AIR!

Today I had few time to spend experimenting new stuff so I decided to try AIR 3.8 BETA on mobile and create something cool to share with you.
As you can see in this short video I create a socket server on my iPhone 4 that interact with a client made on my iPad mini (I tried also with my Android smartphone and it works as well):


To create this sample you needn’t to learn something new, you can use the same APIs you will use on a desktop application, so to create a socket server you write those few lines of code:

//creation of a TCP/IP Socket server
private function createServer():void{
server = new ServerSocket();
server.addEventListener(Event.CONNECT, onConnect);
server.bind(7934); // this is the number of the port where your socket communicate
server.listen();
}

Then, when a client socket will join in the same network and it listens the same port of the server, the magic happens and you can start to comunicate:

//on the server socket application
protected function onConnect(event:ServerSocketConnectEvent):void {
incomingSocket = event.socket;
incomingSocket.addEventListener(ProgressEvent.SOCKET_DATA, onData);}

protected function onData(event:ProgressEvent):void {
if (incomingSocket.bytesAvailable > 0){
//here you can pass data to the client using writeBytes, writeUTFBytes and many other methods
/*an example could be:
incomingSocket.writeUTFBytes(String("HELLO!");
incomingSocket.flush();*/
}
}

// on the client socket application you have to create the connection and then manage (send and receive) data from the server
private function createSocketConnection():void{
socket = new Socket()
socket.addEventListener(Event.CONNECT, connectedToServer);
socket.addEventListener(ProgressEvent.SOCKET_DATA, receiveData);
socket.addEventListener(IOErrorEvent.IO_ERROR, ioErrorHandler);
socket.addEventListener(Event.CLOSE, closeSocket});
//pass to connect method the server IP and the port to comunicate
socket.connect("127.0.0.1", 7934); 
}
protected function receiveData(event:ProgressEvent):void {
// here you can read all the packets sent from the server
}
protected function ioErrorHandler(event:IOErrorEvent):void {
trace("ioErrorHandler: " + event);
}
private function connectedToServer(e:Event):void{
//yes! you are connected to the socket server
}
private function closeSocket(e:Event):void{
//your socket connection is closed
}

After that you can start to experiments with this new feature as I’ve just done.
Last but not least, as you can see on the release notes, Adobe adds another great feature, that is the capability to stop all movieclips are running on the stage calling a new method “stopAllChildren()” directly from the stage instance.
Simple, easy and useful!

360 Flex Atlanta mobile application

Today 360|Flex starts in Atlanta, if you are an attendee or a speaker I make the “official” 360 flex mobile application in Flash Lite 2.

In this app you can find 3 sections:

  • speakers
  • schedule
  • twitter

In the last section (twitter) you can read last post in your twitter and write one in your account.
I use SWX API to create this mesh up, very cool API made by Aral Balkan (thank you man!) that allow to make mesh up of twitter, flickr and so on.

Download zip file and put swf and XML files in your Flash Lite 2 phone….Enjoy!

Obviusly you can have one for Europe event… stay tuned!

UPDATE:

I must say THANK YOU to chall3ng3r that made for me .sis files with SWF2GO, his software that allow to create file for S60 phones.
Thank you man!
Now you can download also .sis file for S60 3rd edition and 2nd edition