Hi to all.

I have to make an offer for a web application.
I have made the analysis and i can estimate the cost / time needed.
What i dont know as i haven't any previous experience either in Windows or Web appls is the part that the user have to pay for his subsricption from the Web Appl.
Has anybody any experience for the needed process and/or library and/or various possible ways to cover this need?
If yes, i would be gratefull if he could share his revelant experience and/or solutions.
This is the only thing it keeps me from making my decision if i can implement the project

Thanks in advance

A.Kyriakos

A.Kyr wrote:

> I have to make an offer for a web application.
> I have made the analysis and i can estimate the cost / time needed.
> What i dont know as i haven't any previous experience either in
> Windows or Web appls is the part that the user have to pay for his
> subsricption from the Web Appl.  Has anybody any experience for the
> needed process and/or library and/or various possible ways to cover
> this need?

I've done a few card processors, and also Paypal just recently. I'd say
they are not too hard to do if you are familiar with REST and similar
funcationality, but your main priority is the server side of things.
What are you using for your server? That is where you have to put your
smart code for this, and you have to be able to handle a redirect from
your EWB application to the payment provider and back.

Documentation for these things is pretty good nowadays. I did PayPal in
a day for basics, and another day for polish. Obviously having done
such things before makes it easier.

If you want to see how I did it, you can visit dev.banxia.com and
create an account. I won't spam you, but you can use the card number at
the bottom to see the verified by visa part in action (click on Accept
in the embedded page that appears). PayPal is done by being redirected
away, and then back again, and I can't give you the test account, so
you'd not see the details. But you can't (I don't think, anyway,
perhaps it might be possible), keep the EWB application live while
PayPal does its stuff, so that complicates it.

Anyway, key thing is you have to have a server to control this code.
You cannot do it in the browser.


--

Matthew Jones

Thank you for your reply/info

<<What are you using for your server? That is where you have to put your
smart code for this, >>
I use a custom made ApplServer with Delphi and KBMMW

<<and you have to be able to handle a redirect from
your EWB application to the payment provider and back.
>>
Could you please say more about this? If the input data is done through WEB interface and their process/verificatrion should be done in Appl.Srv. side, then why you say for redirection to payment provider
and back?
Any more details or links of APIs of well known/established payments providers would be more than wellcome...

If you want to see how I did it, you can visit dev.banxia.com and
create an account. I won't spam you, but you can use the card number at
the bottom to see the verified by visa part in action (click on Accept
in the embedded page that appears). PayPal is done by being redirected
away, and then back again, and I can't give you the test account, so
you'd not see the details. But you can't (I don't think, anyway,
perhaps it might be possible), keep the EWB application live while
PayPal does its stuff, so that complicates it.

I will visit banxia to see what you describe.

In the meantime thanks again

A.Kyriakos



--

Matthew Jones

A.Kyr wrote:

> Could you please say more about this? If the input data is done
> through WEB interface and their process/verificatrion should be done
> in Appl.Srv. side, then why you say for redirection to payment
> provider and back?  Any more details or links of APIs of well
> known/established payments providers would be more than wellcome...
>

Best place is to find a payment provider and look at their
documentation:

https://developer.paypal.com/docs/integration/direct/create-process-order/

https://developer.paypal.com/docs/api/#create-a-payment

The key here is the flow of data, and the "post back". On your server
you talk to the payment processor, and set things up. Then the browser
is directed to their site, and the user enters details or whatever. And
then the browser is redirected back to you with details in the POST
that you can then use to talk to the payment provider to complete the
process. The general idea is that the end user cannot cheat by sending
you "yes, they paid a million dollars, trust me" in the response, but
you get to verify it.

Paypal is free to sign up and get a test account, so you can try it
easily. Their sample documentation shows what you need to do, and what
you need to put in your messages. Other providers are pretty much the
same nowadays, perhaps with the hardest part being the hashing of
content to ensure it is you that is requesting it, and it is them that
returned the data. Note that some credit card payments don't need to
redirect, but you will take the risk on fraud if you don't do the "3D
Secure" part, but 3D Secure can be done in the EWB page (as per my site
and the horrible test page it will show), but it still does a post back
to your server. When you press Accept to verify the card, the server is
told, and the EWB application is checking itself every second to get
status, and when it the server tells it all is good, it hides the
embedded page again.

--

Matthew Jones