RequestAttribute-Selector in Cocoon

The RequestAttributeSelector tests the value of request attribute against the test attribute of the selector's when clause.

The RequestAttributeSelector allows to control the sitemap processing depending on a request attribute.

Sitemap pipeline examples

The snippet below uses a RequestAttributeSelector named request-attribute. It tests the value of request attribute named command against list, create; finally it has a otherwise clause.

<map:select type="request-attribute">
  <map:parameter name="attribute-name" value="command"/>
  <map:when test="list">
  ....
  </map:when>
  <map:when test="create">
  ...
  </map:when>
  ...
  <map:otherwise>
  ...
  </map:otherwise>
</map:select>
        

Sitemap component configuration example

The snippet below declares a RequestAttributeSelector defining to use the request attribute cmd.

<map:selectors...
  <map:selector name="request-attribute" 
    src="org.apache.cocoon.selection.RequestAttributeSelector"
    logger="sitemap.selector.requestattribute">
    
    <attribute-name>command</attribute-name>
  </map:selectors>
...

Configuration

The configuration section of RequestAttributeSelector specifies the default name of the request attribute, used for testing.

Setup

Setting up a RequestAttributeSelector includes

• Defining an optional sitemap paramter named request-name, it overrides the attribute-name setting in the configuration section.
• choosing the <map:when> test expressions, and a optional <map:otherwise> clause.

The test attribute of the <map:when> clause shall match the value of the request attribute. If no test value matches, or the request attribute is not defined at all, the <map:otherwise clause is selected.

Effect on Object Model and Sitemap Parameters

The RequestAttributeSelector has no side effects on the object model, or any sitemap attributes.

28-12-02: initial creation

A general documentation about selectors is available at Matchers and Selectors.