Modernize
Modernize is a tool to build MDS repositories from DSpace repositories. The intention is to greatly lower the barriers to populating a repository for evaluation/exploration, rather than providing a comprehensive tool to migrate from one system to another. Thus, only content objects and metadata are copied, but not users, resource policies, open workflows, etc. It is non-destructive to the DSpace repository, but does require enough scratch space to have a copy of all the content files.
You may select any arbitrary subset of the DSpace repository to convert, where the subset is defined by the subtree under a given handle. For example, if you specify a top-level community, it would grab all the sub-communities and collections under that community, but ignore all sibling top-level communities. If you specify a collection or non-top-level community, it will grab the direct parents up to the root, but no siblings.
Installation
Simply drop the built jar into [dspace]/lib, where [dspace] is your installation (deployment) directory. It is a command-line tool, so Tomcat is not involved.
NB: important limitation! This code requires a Java 7 JRE, regardless of the DSpace version.
Invocation
To run the tool, cd to the [dspace]/bin directory, then type:
./dspace dsrun edu.mit.lib.tools.Modernize -i <handle> -s <scratch> -t <target>
where handle is the community or collection defining the content subset, or 'all' to process the entire repository, target is the URL of an mds repository where you have administrative privileges, and scratch is the name of a directory where the tool can write temporary files. Since creating the serialized version of the DSpace content in the scratch area may not need to be performed more than once, one can in fact run the command without an mds target:
./dspace dsrun edu.mit.lib.tools.Modernize -i <handle> -s <scratch>
This will create SIPs for all the items, collections and communities in the scratch area. Then the command:
./dspace dsrun edu.mit.lib.tools.Modernize -s <scratch> -t <target>
would load them into the target mds repository. One can rerun this command against different targets, since the scratch SIPs are not deleted.
Under the Hood
The tool operates by creating, for each community, collection, and item in the subtree a Bagit-based SIP package, and then using the REST API of the mds repository, POSTs these SIPs. It keeps track of the SIPs by creating a simple map (called export.map) file that shows the relationships among them, so that they can be POSTed to the new repository in the correct order (top community, then collection, then items, etc). Each SIP is named with it's object's handle, although these are not preserved on the MDS repository.