You can limit the set of items to index by setting the IndexingOutputConfig component’s repositoryItemGroup property to a component whose class implements the atg.repository.RepositoryItemGroup interface. This interface defines a logical grouping of repository items. Only the items that are included in this logical grouping will be included in the index.

For example, many commerce applications display search results only for items that can also be viewed by browsing the catalog hierarchy. To be viewed this way, a product must have an associated category. Therefore, the ProductCatalogOutputConfig component’s repositoryItemGroup property is set by default to /atg/commerce/search/IndexedItemsGroup. The IndexedItemsGroup component uses a targeting ruleset to select only products that are properly categorized. Note that IndexedItemGroup has a repository property that specifies the repository that the items are selected from; this must match the repository that the ProductCatalogOutputConfig is associated with.

It is also possible to specify a repository item group in the indexing definition file using the repository-item-group attribute of the top-level item element. If a repository item group is specified in the definition file and also by the component’s repositoryItemGroup property, the value set by the repositoryItemGroup property overrides the value set in the definition file.

IndexedItemsGroup uses the following targeting ruleset, which returns all products that have ancestor catalogs:

<ruleset>
  <accepts>
    <rule op=isNotNull>
      <valueof target="computedCatalogs">
    </rule>
  </accepts>
</ruleset>