Although, I should put some easter eggs in that the php community can enjoy when they fly. When I first started here at Panasonic I was overwhelmed with the amount of resources that actually go into an in-flight entertainment system. Video/Audio departments, how studios actually charge for the ability to show their movies. The Q/A Process alone is pretty interesting. You never quite think about what your web server should do when it senses turbulence(almost everything is written to RAM to prevent data loss in case of turbulent disk writes).
The downside to the system is the unbelievably slow hardware I have to deal with(233mhz, no video drivers). The main interface with the customer is via a touch screen LCD monitor. I work on the crew side, so my applications are developed so the crew can control the system. They can assign video/audio, make announcements, they can see when you press that little button to bug them. I was able to make sure we used Firefox as our Kiosk web browser. I had some experience with the platform and knew the power that Firefox could bring to the table.
One of the first challenges I tackled while I was here was to address the need for a fully event driven system. For example, if I'm playing video on one kiosk machine the other crew machine should exactly match that UI step by step. We had thought about polling however it just seemed like such a cop out, hacky solution, being I controlled the WHOLE environment. I like to think about my traffic as a human conversation. Imagine someone asking you for today's date every second. "hey Jim what's the date?" "hey Jim what's the date?" ugh leave me alone I can't hear you over all this video traffic!!! When the date changes I'll tell you! Now that is why I chose to look into the server push option. Let's let the server tell us when data changes.
Ok, so how do we do that? well in firefox there is the multi-part option of an XMLHTTP request. It will keep a connection alive much like an open iframe and allow a server script to continually loop, pushing out new data. What I didn't like about that when we tested was the scalability of the system. Remember, I have SLOOOOOOOOW boxes and a ton of network traffic with audio and video being streamed to 400+ seats. It still didn't meet my conversation requirement completely. It would be like someone coming into your room and saying "Ok, do you have data? No? Well I'm going to sit in your room, stare at you and wait until you do". We'll that's annoying too. How about when I have data I will give you a call and give you what I have? I can move on with my life and not worry about you being annoying.
That lead to the birth of a basic web server as a firefox extension. It listens on a certain port and takes and acts on live events in the system over TCP(UDP support probably in the future). When the plane takes off that's a "weight off wheels" event. That event then fires into my browser, through my framework, to client code that's observing that event. You could be looking at the screen and the whole UI just seems to be moving on it's own. Quite interesting.
I was going to talk about the handheld solution using Minimo however this is running too damn long. Maybe another day. That's basically a small summary of my past year. I've left about about a million things I wanted to discuss but I'll save those for future articles.