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<DIV><FONT face=Arial size=2>Avi and Julian,</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Suppose your Seaside site user interaction goes
something like this:</FONT></DIV>
<DIV><FONT face=Arial size=2>1. Choose your product</FONT></DIV>
<DIV><FONT face=Arial size=2>2. Pay</FONT></DIV>
<DIV><FONT face=Arial size=2>3. Process the sale</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Now suppose you want step 2 (Pay) to take
place on Verisign's site.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV><FONT face=Arial size=2>
<DIV><FONT face=Arial size=2>It would be nice if I could model this using the
component call: mechanism already in place. eg, I would call
WAPaymentStep which would forward the user to the Verisign site and answer
a PaymentResponse upon "returning" from Verisign's site.</FONT></DIV>
<DIV> </DIV>
<DIV>
<DIV><FONT face=Arial size=2>There are two parts to this problem: </FONT></DIV>
<DIV><FONT face=Arial size=2>1. Sending them to the payment site and
</FONT></DIV>
<DIV><FONT face=Arial size=2>2. receiving them back to Seaside after
payment.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>1. This part is easy: WAPaymentStep presents a form
to the user that upon submission posts the necessary variables to the payment
site.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>2. This is the hard part. Here's my plan so
far...</FONT></DIV>
<DIV>WAPaymentStep needs to register a callback that would </DIV>
<DIV>a) process the POST from Verisign site (their response) and create a
PaymentResponse object</DIV>
<DIV>b) return the Payment Response using #answer:. </DIV></DIV>
<DIV> </DIV>
<DIV>What I would like is:</DIV>
<DIV>Example code on how to register an arbitrary callback block.</DIV>
<DIV>Does such a callback have access to POST variables? If
not, can you suggest another way to get posted variables into a smalltalk
object which gets "returned" using #answer: ?</DIV>
<DIV> </DIV>
<DIV>I can imagine another Seaside service called "VerisignService" who's job it
is to accept responses from Verisign and leave an appropriate PaymentResponse in
a "mailbox" to be picked up by WAPaymentStep. VerisignService then calls
some continuation to "wake up" the WAPaymentStep, which "checks its mail" and
returns the PaymentResponse using #answer: .</DIV>
<DIV> </DIV>
<DIV>Any ideas would be appreciated.</DIV>
<DIV> </DIV>
<DIV>Thank you.</DIV>
<DIV> </DIV></FONT>
<DIV><FONT face=Arial size=2>Derek Brans<BR>Nerd on a Wire<BR>Web design that's
anything but square<BR><A
href="http://www.nerdonawire.com">http://www.nerdonawire.com</A> <BR>mailto: <A
href="mailto:brans@nerdonawire.com">brans@nerdonawire.com</A><BR>phone:
604.874.6463<BR>toll-free: 1-877-NERD-ON-A-WIRE</FONT></DIV></BODY></HTML>