The OrderForm

The OPP requires that data passed from the site to the OPP, and from the OPP to the site, be passed in an OrderForm object. This requirement applies both to components included in the default OPP and to components designed to extend its functionality.

The OrderForm consists of a structured set of Dictionary and SimpleList objects that makes it possible to present a detailed summary of all or part of one or more shopping sessions to the customer or to the OPP. This summary includes customer data, such as name, address, and credit-card information, as well as product information related to the purchase.

As the preceding diagram illustrates, the OrderForm is a Dictionary. The first element in this Dictionary is a reference to a SimpleList of the items that make up the order, and each of these items is itself another Dictionary. The SimpleList is referred to as the items list.

The elements that make up both the order Dictionary and the Dictionary objects in the items SimpleList are called name/value pairs. Each component that you include in the OPP for your site is designed to operate on one or more of these name/value pairs. Typical operations include the following:

• Name/value pair creation. Several components create name/value pairs in an OrderForm. For example, the QueryProdInfoADO component queries a specified database table for information on a given product, prepends _product_ to the column name, and adds the resulting name and the value for the associated row to the OrderForm.
• Name/value pair initialization. The required components in the OPP fall into this category. These components check to make sure that certain name/value pairs are initialized, and if they are not, these components initialize them. Thus, the RequiredOrderInit component, which is part of the Order Initialization stage sets the _total_total, _oadjust_subtotal, _shipping_total, _tax_total, _handling_total, _tax_included and _payment_auth_code name/value pairs to Null.
• Name/value pair verification. The OPP fails if certain name/value pairs on an OrderForm are not initialized when the pipeline is invoked. For example, the RequiredOrderInit component verifies that the items SimpleList on an OrderForm is not empty. If this SimpleList is empty, the component returns status indicating failure.
• Name/value pair calculation. The optional components in the OPP initialize name/value pairs based on the work performed by other components. For example, the components in the Tax stage calculate the tax on an order, based on the list of items in the OrderForm's items SimpleList, and writes the tax to the _tax_total name/value pair.

The underscore (_) character that precedes many of the name/value pairs in the OrderForm is known as a prefix. Generally, the inclusion of a prefix indicates the name/value pairs in an OrderForm that are not persistently stored.

Note  The contents of an OrderForm can vary, depending on how the pipeline for a site is configured. The figure listed previously is intended only to illustrate a typical OrderForm.

Related Topic

• Values Commonly Used on the OrderForm