A feedable is an object which is generated from the data of a content bean and which the CAE Feeder sends to the Search Engine for indexing. Customizing feedables means that you define which content of a content bean is mapped to fields of the feedable and is therefore added to the index if a corresponding Solr index field exists. The following paragraphs describe the involved classes.

The FeedableContentBeanEvaluator creates feedables from ContentBean objects. You can find the configuration in the file caefeeder-triggers.xml, which is located in the classpath /framework/spring/caefeeder.

<bean name="contentEvaluator" class=
"com.coremedia.amaro.cae.feeder.FeedableContentBeanEvaluator">
  <property name="contentBeanFactory" ref="contentBeanFactory"/>
  <property name="keyTransformer" ref="feederKeyTransformer"/>
  <property name="feedableFactory" ref="feedableFactory"/>
  <property name="feedablePopulator"
            ref="errorHandlingFeedablePopulator"/>
</bean>

An implementation of com.coremedia.cap.feeder.persistentcache.KeyTransformer is used to create identifiers for Search Engine documents in the index. The default KeyTransformer implementation creates identifiers of the same format as the IdProvider of the CoreMedia CAE.

Example: a content bean for the content with the numerical id 42 is represented by an Apache Solr document with the value contentbean:42 in the field id. Search applications can use the IdProvider to get a content bean for the identifier again.

The FeedableContentBeanEvaluator uses an implementation of com.coremedia.cap.feeder.populate.FeedablePopulator to fill the elements of the feedable with the values of a content bean. By default, a BeanMappingFeedablePopulator is used which maps Java bean properties of ContentBean objects to elements of the created feedable as configured.

If required, you can configure additional FeedablePopulator implementations in the property populators of the bean compositeFeedablePopulator. The property takes a list of FeedablePopulator<T> beans, which makes it possible to combine data from different implementations into the same feedable. The type parameter <T> of a configured FeedablePopulator bean must be ContentBean, Content or a super type of these. You can find some existing FeedablePopulator implementations in package com.coremedia.cap.feeder.populate. For example, you may configure an additional PropertyPathFeedablePopulator to index certain nested values of struct properties.

If a bean property's get method throws an exception, the CAE Feeder will index a so-called error document in the index as placeholder. Error documents can be recognized by the value ERROR in the index field feederstate. The stack trace of the exception is stored in the index field feederinfo. Do not forget to always add a feederstate:SUCCESS clause to your queries to find successfully indexed documents. Bean feeding will by default automatically be retried after 10 minutes or if a dependency is invalidated that was accessed before the exception was thrown. Errors are handled by an instance of class com.coremedia.cap.feeder.populate.ErrorHandlingFeedablePopulator which wraps all FeedablePopulator instances. It is available in the Spring Context as bean errorHandlingFeedablePopulator and can be customized as described in its API documentation.