Ah yes, therein lies the rub. Most, if not all, carts I've seen are built to be complete (sub)sites in and of themselves. They're meant to be turnkey systems, but the tradeoff is that they tend to insist on owning the layout and everything. You have to go diving through the code and substantially modify them in order to get a certain "look and feel" compatible with the rest of your site. The cart can be a standalone site, so it may bring in all sorts of extra baggage that's not wanted and may even interfere with integrating the cart into a larger site.


It appears that "drop-in" cart functionality like PayPal's is rather limited compared to "all-in-one" solutions. You keep the look and feel of the rest of your site, at the cost of having very limited cart capability.


I would recommend against trying to re-invent the wheel -- lots of people have put lots of effort into making commercial-grade shopping carts very robust and very capable. Customers and (worse,) hackers will find all sorts of holes in any home-brew cart.

I have spent quite a few months going over the code in osCommerce to further modularize it, make it MySQL 5 compatible, and in general streamline it. My intent is to split it up into modules and to have some number of "templates" or frameworks into which all these modules are plugged in, rather than the existing large number of monolithic pages. The look and feel of each page would be in its template, while most of the functionality would be the plug-ins. The idea is that osCommerce would ship with a vanilla page layout (header, footer, three columns) so that it continues to be a turnkey system. However, you could replace the templates with your own page templates to match the rest of your site. They might include all or only part of current available function. Furthermore, you could have custom content for each item, by pointing to your own code files, rather than accepting their "one size fits all" one image and and a bunch of text for each item. Something like that. You would also be able to select the template or style used based on category, subcategory, item, etc.

My current job (50-60 hour weeks) leaves me mentally exhausted by the end of the day, so I'm not making much headway on this right now. However, if there's sufficient interest, maybe I'll stir myself to take another crack at it. I've always intended to offer it back to osCommerce as a new framework for their version 3.0 or 3.1 (which I have no idea what will look like). If they don't want it, maybe I'll fork it off into a new product?

Weeellllll.... it's complicated.

I view something like (the current) osCommerce, something that can work as a standalone site, as "inside-out". The ecommerce code forms the backbone of the site. As I discussed before, the layout and such could be a bit more easily customizable, but in the end you're still playing with the skin over an ecommerce system. That is not in itself a bad thing, provided you can bend, stretch, and hammer that skin to look and feel like the rest of your site.

On the other hand, I view something like the PayPal "drop-in" purchase code (buttons) as "outside-in". Your own code forms the backbone of the site, and the PayPal button is "grafted on" to your site. While this means that you have better control over the look and feel of your site, there are several major problems. One is that it's likely that you have to maintain the inventory database and such yourself, rather than having the ecommerce code manage it for you. Another is that the resulting function doesn't look and feel smoothly integrated -- as you point out, new windows pop up and users get taken off site.

I suppose it might be possible to take all the function of something like osCommerce and break it up into chunks that you could call from your pages, to manage the inventory, add items to cart, do the checkout, etc. However, I think it would be cleaner and safer to have an underlying integrated ecommerce engine (such as the osCommerce core) running, and use mix-and-match interface components to plug into your pages to provide the skin. That's what I'm trying to get to with my work. BTW, osCommerce 3.0 may be heading in roughly that direction -- it may be worth checking that out.

By the way, what do you mean by "Often that means setting up an account in Paypal."? Does using the PayPal "drop-in" button code somehow limit your payment options? (I haven't tried it.) Regular PayPal does (AFAIK) permit credit card payment without the visitor having to open up an account.

Wowzers.

I just went over to Paypal and realized they do have a procedure for allowing customers to pay without creating an account. I had to upgrade to a business acct, but it's about 50% of the solution I'm looking for. (The other 50% would be if the user stayed on-site the whole time).