Encode once or dynamically?

I want to set up a level 1 shopping cart, but I'm a bit
confused about
the necessary encoding and encryption.  Can I just write out
my code,
encode and encrypt it once, and then place it into my page
as plain
html, or is it necessary to use a scripting language to do
this
dynamically with every order?  If it only needs to be
encrypted once,
could google create a page under checkout integration that
will take
our code and merchant key and encode them for us?  I'd
really
appreciate that.

Nick,

To clarify, you need to dynamically base64-encode your
shopping cart
XML and generate its digital signature everytime a shopping
cart is
posted. For more information on how to post a shopping cart,
please
refer to our Developer's Guide at
http://code.google.com/apis/c
heckout/developer/index.html#submit_cart_and_signature

Or you could post the shopping cart by using the alternative
technique
as explained here:
http://code.google.com/apis/check
out/developer/index.html#alternative_technique

Also, it might help if you look at the sample code that we
provide to
see how it's really done:

http://code.google.com/apis/checkout/samplecode.html


Thanks,
Jacob