The Tax stage and other tax components ensure that order._tax_total and order._tax_included keys are set. If not, an error is generated.
If you want to use the Site Server 3.0 Commerce Edition components, you will not be able to use the Splitter, ShippingMethodRouter, and StepwiseShipping components. For information about using Site Server 3.0 Commerce Edition shipping methods, see Using Site Server 3.0 Commerce Edition Shipping Components.
You can run all of the components in the Tax stage unless a fatal error is returned. To cooperate, one component in the tax stage must set the _tax_total key, or a shopper warning is raised. Each component must check the resulting _tax_* values. If these values are already set, the component should return without doing anything. If the values are not set, the component will attempt to calculate the tax and if it is successful, set the _tax_* values.
In addition, some Site Server 3.0 Commerce Edition tax components require that the value of the _ship_to_country key is set to the intended country/region; otherwise, the component will not run.
In each of the tax components, the country/region name can be specified as a parameter even though the name of the country/region is part of the name of the component (for example, SimpleCanadaTax). This is because the name of the component describes only the model for computing sales tax, and not the country/region to which it applies. For example, another country/region might use a tax model similar to Canada's model. Because the country/region name is specified, the tax model (and its corresponding component) can be used for more than one country/region.
See Also
DefaultTaxCy, DefaultTax
SampleRegionalTax
SimpleCanadaTax
SimpleJapanTax
SimpleUSTax
SimpleVATTax
RequiredTaxCy, RequiredTax