Major Java API refactor, supporting UUIDs and Hibernate. The DSpace Java API has been refactored significantly to make it more modular, and make it easier to achieve future RoadMap modularity goals. For more detailed information, see DSpace Service based api or DS-2701. This feature was contributed by Kevin Van de Velde of @mire, with support/help from the DSpace Committers.

• Hibernate allows us more stability in our database layer (decreases the likelihood of database specific bugs), and potentially allows us to support additional database platforms in the future
• UUIDs provide all objects with stable, globally unique identifiers (instead of existing incremental, non-unique database identifiers). This simplifies the management of identifiers in our object model.
• The Java API itself is now split into three "layers" which are all now initialized via Spring
  
  • Service layer, which contains DSpace business logic
  • Database Access Object (DAO) layer, which contains specific Hibernate database queries to locate/find individual objects
  • Database Object layer, which provides access to specific database columns, object properties via Hibernate

Most sites will not notice this major API refactor, as the upgrade is seamless. However, if you've performed major (Java-level) customizations, you may need to refactor your own customizations to use this newly refactored API. Some examples are on the DSpace Service based api page.

Enhanced (Reloadable) Configuration System. See Configuration Reference, Enhanced Configuration Scheme and DS-2654. This feature was contributed by Tim Donohue of DuraSpace.

• Provides easier management of local configurations via a new local.cfg file. Any configurations (from *.cfg files) can be overridden in DSpace by simply copying them into your local.cfg and changing the value. See Configuration Reference
• Many configurations now automatically reload as soon as you save your local.cfg file. This means you don't need to restart Tomcat every time you need to change a configuration.
  • Please note: Unfortunately, at this time, some configurations do still get cached in the XMLUI or JSPUI (or similar). So, while many will reload, not all of them yet support this feature.

Enhanced file (bitstream) storage plugins, including support for Amazon S3 file storage. This feature was contributed by Peter Dietz of Longsight.

• Configuring the Bitstream Store (also see https://github.com/DSpace/DSpace/pull/1159)

Configurable site healthcheck (i.e. repository status) reports via email. This feature was contributed by Jozef Misutka of Lindat.

• Healthcheck reports (also see DS-2659).

XMLUI new features

• New framework for metadata import from external sources (including an out-of-the-box plugin supporting PubMed, and hopefully more coming soon). This concept was previously only supported in JSPUI. Screencast example: http://screencast.com/t/QBImSGbAUZ.  This feature was contributed by @mire.
  • Framework: DS-2876
  • PubMed metadata import: DS-2880
• Extensible administrative control panel, allowing institutions to override or customize the XMLUI administrative "control panel" (see also DS-2625). This feature was contributed by Jozef Misutka of Lindat.
• Export of XMLUI search results to CSV for batch metadata editing. This feature was previously only supported in JSPUI. See also DS-1262. This feature was contributed by William Welling of Texas A&M

REST API new features

• REST Based Quality Control Reports for collection manager. See also DS-2583. This feature was contributed by Terry Brady of Georgetown University
• Support for all authentication methods via REST (e.g. Shibboleth, LDAP, etc)

Features Removed or Replaced

• The build.properties configuration file has been replaced by an enhanced local.cfg configuration file. The new local.cfg allows you to easily override any configuration (from dspace.cfg or modules/*.cfg files) by simply copying it into your local.cfg and specifying a new value. It also provides enhanced configuration options as detailed in the Configuration Reference documentation. The old build.properties file is no longer used nor supported.
  • WARNING: As part of adding this new configuration scheme, many of the configuration settings in DSpace (primarily those in modules/*.cfg files) had to be renamed or prepended with the name of the module. This means that 5.x (or below) configurations are no longer guaranteed to be compatible with 6.x. If possible, we recommend starting with fresh configs (see below), and moving all your locally customized settings into the new local.cfg file.
• The PDF Citation Cover Page configuration file has been renamed (from disseminate-citation.cfg to citation-page.cfg). See this features documentation for more details.
• The legacy search engine (based on Apache Lucene) and legacy Browse system (based on database tables) have been removed from DSpace 6.0 or above. Instead, DSpace now only uses Discovery (based on Apache Solr) for all Search/Browse capabilities.

• The DSpace Lightweight Networking Interface (LNI), supporting WebDAV / SOAP / RPC API, has been removed from DSpace 6.0 or above. We recommend using REST or SWORD (v1 or v2) as a replacement. However, if you still require it, the old (unmaintained) LNI codebase is still available at https://github.com/DSpace/dspace-lni

• Support for SRB (Storage Resource Broker) file storage has been removed from DSpace 6.0 or above.  As it was unmaintained (and seemingly unused) for many years, this feature was removed along with its configurations. As a replacement, a new file storage plugin system was added, featuring a traditional local file storage option (default) and an Amazon S3 file storage option (see Storage Layer documentation, especially Configuring the Bitstream Store). For more information on the removal of SRB support, also see DS-3055.
• The user groups Administrator and Anonymous cannot be renamed or deleted.  If you had renamed them, they will be renamed back to the stock names during the upgrade.  DSpace is now dependent on these specific names due to internal changes.