External Search

Define Indexing Namespace and Mixin in CND of fcrepo4

External indexing relies upon the objects you wish to have indexed to have an indexing:indexable mixin property. This can be done using the REST interface or via the fedora-node-types.cnd

Definition using the REST interface

Go to http://localhost:8080/rest/fcr:namespaces and in the Register Namespace form add:

     Prefix: indexing

     Namespace: http://fedora.info/definitions/v4/indexing#

Go to http://localhost:8080/rest/fcr:nodetypes and in the Update CND form add:  

[indexing:indexable] mixin
- indexing:hasIndexingTransformation (STRING) multiple COPY nofulltext noqueryorder

Definition via fedora-node-types.cnd

Make sure your node definitions contain the following:

<indexing = 'http://fedora.info/definitions/v4/indexing#'>

[indexing:indexable] mixin
- indexing:hasIndexingTransformation (STRING) multiple COPY nofulltext noqueryorder

The standard configuration chain is as follows:

1. fcrepo4/fcrepo-webapp/src/main/webapp/WEB-INF/web.xml contains a context-param element with param-name "contextConfigLocation".  The param-value points to your spring configuration file, usually a path like WEB-INF/classes/*.xml
2. One of you spring configuration files is repo.xml that contains a property repositoryConfiguration defining the location of your repository.json
3. fedora-node-types.cnd is defined in you repository.json

Configure fcrepo4 messaging

 fcrepo-webapp/src/main/resources/spring/jms.xml contains the bean definitions used by the repository for messaging.  Currently the DefaultMessageFactory is used to implement messaging:

<bean class="org.fcrepo.jms.headers.DefaultMessageFactory"/>

Install standalone search applications

fcrepo-jms-indexer-pluggable currently supports the following triplestores:

• Jena Fuseki (Fuseki setup instructions)
• Sesame (Sesame setup instructions)

fcrepo-jms-indexer-pluggable currently supports the following indexer:

• Apache Solr (https://cwiki.apache.org/confluence/display/solr/Getting+Started)

Install and configure fcrepo-jms-indexer-pluggable

The following github page has detailed instructions as to how to set up fcrepo-jms-indexer-pluggable.  This standalone app listens to messages produced by fcrepo4 and invokes the search applications as configured:

https://github.com/futures/fcrepo-jms-indexer-pluggable

Load an LDPATH program

The following is an example of loading a LDPATH program called "custom".

curl -X POST -H "Content-Type: application/rdf+ldpath" -d "@post.txt" "http://localhost:8080/rest/fedora:system/fedora:transform/fedora:ldpath/custom/fcr:content"

post.txt:
@prefix fcrepo : <http://fedora.info/definitions/v4/repository#>
id      = . :: xsd:string ;
title_tsi = dc:title :: xsd:string;
uuid_ssi = fcrepo:uuid :: xsd:string ;

Note that for solr indexing the field name (such as id, title, and uuid) must be match the fields that are defined in the solr schema.xml (see solr documentation: https://cwiki.apache.org/confluence/display/solr/Solr+Field+Types).  One recommended schema.xml is provided by hydra-jetty (https://github.com/projecthydra/hydra-jetty/blob/master/solr/development-core/conf/schema.xml) which has a robust set of default dynamic fields.

Create objects with indexing properties

For an object to be indexed it must have a rdf:type of indexing:indexable, and optionally a indexing:hasIndexingTransformation corresponding to an LDPATH program.

curl -X POST -H "Content-Type: application/n3" "http://localhost:8080/rest/anIndexableObject" -d "@body.rdf"

body.rdf:
@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
@prefix indexing:<http://fedora.info/definitions/v4/indexing#>.
<> rdf:type  <http://fedora.info/definitions/v4/indexing#indexable>
<> indexing:hasIndexingTransformation "default".

TODO: test