ajax

[dclamp]

My next project i am going to start is going to be a Point Of Sale system, written in PHP, and sometimes servers can take a minute to load so i thought i would implement AJAX into it to speed up the process

Has any one used AJAX technology? Did you like it? did you find it easy?

[penagate]

Why would you write a PoS system in PHP? It seems quite an inappropriate language to pick.

[dclamp]

well why not? i offers the remote capability to use the software in any location.

[CodedFire]

Why would you need to use it in any location. Most pc's that have a POS on then would have some sort of pc anywhere on them. This would be a classic case of trying to fit a square into a circle.

You need to learn a second language. Many programmers hit this wall eventually were they try use one language for every purpose. PHP would not be structured enough for a POS. Most POS systems are built to customers specs along with a backend system. This means you would need a team of guys along with the most important part. A customer.

[dclamp]

i dont understand what your saying.

it is possible to make one with php... it may not be the best language to use. but it would still work.

[si_the_geek]

Possible? Yes.
A good idea? No.

It would be similar to using a brick to press the buttons on a remote control. It will probably do the job... but unless you are extremely careful, it wont be safe.

By definition, a PoS system is supposed to be running at the Point Of Sale, and monitor goods and/or money. By having it running remotely, you open up an extra loophole for people to modify the data, and steal the related goods/money (or for their competitors to read the data).


Just like the classic saying, "When the only tool you have is a hammer, everything looks like a nail". In this case, it isn't a nail - so you should get yourself a different tool (programming language), rather than just swinging that hammer.

[dclamp]

i think we are seeing it differently.

There would be one "main" server with the database and PHP POS script on it.

then there would be other computers that can connect to the server and allowed to access the script, based on their IP address.

so only IP address that are allowed to access it, can see it.

[CodedFire]

People still wouldn't buy it. 90% of PoS systems are tailored to individual customers. Take vodafone as an example. we have 56 epos machines. 46 track all movement of phones, 10 do not.

This means that 46 of our epos systems are different builds to the other ten. Of the 46, 2 are currently connected to suppliers for ordering and dispatching phones. This means we now have 3 different builds

The guys who supply us with our EPOS have a customer base of around 1000 people, each with these sort of requirements

Couple that with an extremely advanced reporting system in head office that is again tailored to suit are needs and you begin to realise two things.

An epos cannot be made whole, its basicly a selection of tailored parts. This means you would have to host every single build of your epos seperatly. Also we have an audit done on the security of our epos machine every six months. These are very strict. So much so that data can only be sent to the epos systems at specific times of the day.

This basicly means our epos systems operate on a closed sytem that can only dail in at certain times.

You could make this system, im not saying you can't with PHP. Im merley saying it is not the best way to do it. Its like making a car out of wood, its possible but not the best way of doing it.

[dclamp]

well then. I must say then this project has taken a fall

and i didn't even get my original question answered...

[CodedFire]

Happy to help!

[si_the_geek]

i think we are seeing it differently.

Even after reading the rest of your post, I don't.

Why would this be web-based at all?

Surely a couple of important points for a PoS system is that (as far as possible) they should be quick to use (not having to wait to load a new page from the server), and keep working all the time (even if the server has a problem). Slowing down the business is a bad idea as it costs them money (in terms of staff/equipment/sales), and stopping the business (even for a few minutes) is a nightmare.

By using a web based setup, you have a single point of failure - something that should not be acceptable for a business critical system.

If you use a desktop application setup instead (along with a central database), you could have the clients keep working, and then write the appropriate data when the server is active again. Also, if one of those clients fails, only that single client is affected - the others can still be used.


You could create desktop apps in PHP, but even php.net doesn't exactly recommend it:

PHP is probably not the very best language to create a desktop application with a graphical user interface, ...

Even tho you seem to have given up on the idea of this system while I was writing this post (and taking a break ), keep in mind that adding different types of languages to your skill-set is definitely a good move, and not just because you can create more appropriate apps for the situation - you also learn different programming methods, and get a much better understanding of programming (rather than just understanding a particular language).

[Davadvice]

hi, I cannot answer your question however, there are some great cars made from wood. the morgan is the one that springs to mind just now.

as for the project i believe the more ppl say it can't shouldn't be done the more determined i am to do it. Good luck with it. you may just discover somthing that no one else has.

David

[FishGuy]

Give c# or vb.net a try that way you will learn a new langueage and it will be one you can apply to both web apps and windows apps, or windows apps that consume web services.