Conclusion
The coding challenge was to find some way to distinguish the companies, all of which now resided on the same server, and thus had the same applet codeBase. I chose to have the applet read the documentBase for the particular HTML page, and to snip out the portion which represented the merchant's particular root directory. No matter what sub-directory the browser was in, the portion at the beginning of the http:// address, up to and including the root for that merchant, would always be the same. The first applet parameter, named "start," told the applet where to begin snipping. The second, named "value," told it where to stop. For instance, if the merchant address was http://www.infinitestores.com/oneMerchant, "start" in the zero-based count would be 29, and length would be 11. This would snip out the string "oneMerchant," and ShopPanel could then place it in the slot reserved in the small business version for shippingAndHandling.
Every merchant would call the same applet, preferably using a CODEBASE=http://www.absoluteAddressOnServer call (for an example, view the source at http://209.87.142.42/is1). The fact that the absolute call was for an applet on the same server as the document would ensure HTML memory. However, an absolute call would mean that there would be no need to keep track of directories and sub-directories. This could be important on a large site with multiple servers. Every time the applet was reactivated on some page, it would reload the parameters from that particular HTML page, and if these were different from those in some other reactivation on another page, the values would be modified. Merchants could thus be distinguished.
The company director told me that, in his experience, many orders were canceled at checkout when buyers realized the full impact of shipping and handling. He wondered if it was possible to place a price in the cart that reflected the full cost of shipping and handling. I suggested that he include a call in ShopPanel to the appropriate database on his site, and update the price as desired. There would be an initial result, from numbers placed into the HTML (probably by his databases, perhaps using active server pages), and then a few moments later an update (taking account of volume discounts based on amount purchased, if applicable, and so on). Since JAVA is multi-threaded, and separate from HTML, this could take place simultaneously with other purchases, and independently of HTML page transfers. Since pseudo-constructors maintain the JAVA frame and code when off-site, it would not matter if the buyer jumped elsewhere in the middle of an update. With code size reduced to 13K, there was plenty of room.
Using this modified cart, the company could now handle both a multi-merchant cart, and small business carts. If the applet codebase in the checkout querystring was the company's site, then the company would know that the shippingAndHandling slot for each product provided the respective merchant's unique directory name, and interact with databases appropriately in order to finalize the order further. Alternatively, if the applet codebase was something different, then that codebase would be the merchant's identity - it would be unique because every http:// address is different. All aspects of a small business transaction would be automated - from initial sign-up, to database maintenance through an optional text file on the merchant's server, to shipping and handling calculations (according to coded instructions in the shippingAndHandling string for each product). Since there would be no need for personal communication, it would make economic sense to deal with the small merchant.
Everything would be interrupt driven: from JavaScript event handlers inserted into elements on an HTML page calling the applet to indicate a purchase; by the applet calling an appropriate database for information; or by the user finalizing an order and through this, sending a querystring to an order-handling section. Persistence would be maintained on the browser, freeing up central server resources, and ensuring a fast connection. There would be smooth interaction between merchants hosting on the same site, and those hosting on other servers.
The multi-merchant version of the cart at present retains the shippingAndHandling field in the HTML coding, even though this information is no longer needed by the multi-merchant site - shipping and handling would be handled through interaction with various databases. The fact that the HTML is unchanged allows a particular merchant to move back and forth easily from hosting at the Seattle company-- with the advantage of placing his orders on a single shopping cart with those of others-- to hosting elsewhere for less money, with the penalty of having his own cart. He does not have to make HTML modifications to his site. Class ShopPanel in the multi-merchant version in turn overrides any ShippingAndHandling information that it receives and instead passes on the merchant's directory string. The fact that the querystring format is unchanged in the multi-merchant version presumably should make things easier at the server end.
I look forward to seeing modifications that will be made by other Open Source developers, and implementations by various companies. I trust that competition will bring us quality service for a low price.
by Lane Friesen
lanelise@dowco.com
- June 2000
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