Custom request attributes for servlet caching

We can create custom request attributes for servlet caching by adding them to the <map> tag.

In a store that runs in the Transaction server, the DynaCacheFilterMappings component tag in the wc-server.xml file has a property that defines several <map> tags.

In a store that runs in the Store server, set this configuration in the workspace_dir/xml/config/wc-store.xml file. Each <map> tag defines how a request attribute can be added to the HttpServletRequest object. Each <map> tag can specify the following attributes:

className

The fully qualified Java class name of the class that provides a static method that can be called to determine the attribute value.

dynacacheAttributeName

The name of the attribute to be added to the HttpServletRequest object.

methodName

The name of a static method of the class specified by the className attribute. The static method returns a java.lang.String and accepts the following parameters:

javax.servlet.http.HttpServletRequest

The request object

com.ibm.commerce.command.CommandContext

The command context for this request

java.lang.String

The name of the attribute (the value of the dynacacheAttributeName <map> configuration attribute).

When the returned String value is not null and is not empty, it is added to the HttpServletRequest using the setAttribute method.

We can call the MyClass.getMyAttributeValue method on each request to generate an attribute value for a request attribute named "MyAttribute", which is then added to the request object. To call this method on each request, specify the following <map> tag:

<map
   className="com.mycompany.MyClass"
   display="false" dynacacheAttributeName="MyAttribute"
   methodName="getMyAttributeValue" name="getMyAttributeValue"/>