I posted a G+ yesterday where I was basically saying: all clients apps will be HTML5/JS at some point on mobile/tablets/desktop, and what we call "web applications" on server side, are just becoming a bunch of specialized web services, or proxies that route calls to backends.
The post had a lot of feedback and that was pretty cool to have the experience of many developers. Most of them agreed with the general idea, and I thought it would be interesting to blog it here - refined with all the feedback.
2000 - 2012
When I think about my first years of developement, we were doing heavy clients using tools like Borland Delphi and the server was just the SQL Database. That was before 2000. Doing an application UI in the web was inconceivable. The only applications we had in the browser were desktop applications hidden in ActiveX components - and some Java ones for the brave. We had rich clients made with some desktop GUI toolkits, and some ugly looking web apps. BB forums anyone?
But if you are a developer of that generation, you've witnessed the growth of the web ecosystem like I did.
We built feature-loaded web frameworks and started to create amazing web apps, backed by new HTML/JS technologies like the 2004 buzzword ajax. They were so amazing compared to what we had before in the browser, that they just killed some of their desktop applications counterparts.
Think about mail clients: the first web mails we had, had a poor UX - and then GMail changed the game. Nowadays, I guess it's easy to predict that desktop mail apps are going to disappear at some point.
So until the last few years, the typical ecosystem was an amazing set of tools on the server-side, that included zillions of template engines, to produce rich web pages.
Of course, we started to include more and more display logic on the client side, using jQuery and async calls over the server.
But the server was still where everything was happening, from the DB calls to the HTML page rendering.
And right now we are shifting
2013 - ?
We're moving away from the model I've described earlier. That move is obvious to many developers, but the big crowd of devs out there (that includes me) is still doing the classical server-side MVC development, when sometimes they should ponder what could be pushed on the client side - for instance everything related to rendering a display.
And the HTML/JS ecosystem is gaining a lot of maturity. So much that the server-side web frameworks role are starting to change slowly: it's not that big framework that's responsible to render HTML pages anymore, doing all the heavy-lifting of calling backends and databases.
It's becoming just a proxy in front of database systems, or specialized web services, that sends back JSON responses to the web browser, and let it handle all the templating and all the display work.
Micro-frameworks are getting a lot of traction for that reason: the web app become either that thin link between a smart JS app and a solid database systeme, either that specialized web service that provides some business logic.
Web sockets offer real-time capabilities that are quite amazing. You can potentially offer interactions between users within the browser with a very simple server that just keeps track of sockets. (that introduces other scalability issues though)
With CORS, it gets even further: a Javascript application can now connect directly to various web services located on different servers.
For instance, if there are no complex security/permissions needs, you can probably call directly servers like Elastic Search to provide a search feature.
You can build diagrams by doing queries to a DB backend, with a minimal server layer that just routes your calls.
And soon enough, local storages will be a standard thing in Javascript applications.
Last but not least, all the responsive design techniques let people build interfaces that will work on different screen sizes.
The boundaries between your mobile, your tablet and your desktop computer are getting fuzzier. They're becoming devices with different screen sizes now, with different storages and CPU powers, that are just powering a web browser.
You get the idea: an HTML page with some Javascript can do a whole lot of things that used to be done on the server side.
I would not be surprised if one day Firefox OS is used on the desktop :)
To quote someone on G+:
This is exactly my experience. My server side has evolved to basically a simple REST layer plus a zeromq/protobuf -> Websockets/JSON translation and routing layer. With backbone/knockout/angular etc on the front end, there's not really much else I can see needing to do in the backend.
So I believe we're going to a world where any connected device, including your desktop, is made of HTML/JS apps, and that the complexity of our applications are moving around, towards a much cleaner layout: everything related to display on the client-side, and everything related to business logic, data etc, on specialized backends or databases systems - but moved out of those big web frameworks we still all use a bit.
If you are a server-side guy like me, you ought to love all those micro frameworks, and to build a bunch of small, specialized web services that all together, can power-up a Javascript app.
In fact, I think Python is becoming the secret weapon behind every good Javascript application ;)
Or... maybe we're just cycling again and again, as JR states it:
I always think that there is some imaginary pendulum that swings between extremes. At first, everything was done on the server, then PCs were introduced and people moved complexity there with the server holding data. Then the web was born and complexity once again shifted back to the server, and now that browsers are more capable, the focus is again shifting to the client.
If you want to comment, I'd suggest doing it in the G+ thread since it started there.