This page describes a minimal DSpace LNI client. It was designed to
be called from an application that produces
DSpace SIPs and ingests them through the LNI,
but it can also function as a standalone command-line application.

UNSUPPORTED: This is unsupported code. Use it at your own
risk. It is simple enough that reading the code and examples should
be enough to answer any questions you may have, but if not, there
may not be any other help available. It is provided freely to the
DSpace community but there are no support resources available.

What it Does

First, see the Lightweight Network Interface
for a description of the LNI. This is an LNI client, the part that
runs on your local computer and talks to a DSpace repository.

This is a very minimal client: it stands completely alone without
any of the DSpace codebase. It is useful as example code and could be
extended.

This client does not give access to all of the operations offered by
the LNI. It only exposes public methods for the GET and PUT
operations, which transfer DSpace Items as packages. GET of Bitstreams
is not covered, although the LNI server allows it.
It implements a
couple of other operations (GET of lookup URLs and the PROPFIND verb)
internally but they are not available as part of its API.

Example Code

The best way to illustrate the toolkit is through an example.
This code fragment ingests an Item (in the form of a DSpace METS SIP)
into a target collection named by its Handle:

  import edu.mit.libraries.facade.app.LNIclient;

  String collection = "some-handle";
  LNIclient lni = new LNIclient("http://mydspace:8080/lni/dav/", "eperson@my.edu", "password");
  OutputStream os = lni.startPut(collection, "METS", null);

  // your application creates a SIP and writes it to the stream
  your-code-to-write-METS-package-to-stream(os);

  os.close();

  // now your application records or displays the new Item's Handle.
  String newItemhandle = lni.finishPut();

For more examples, see the main() method in the source, since
it implements the command-line LNI client.

See the source code, which has Javadoc-style comments, for more
complete documentation. You can also use javadoc to create
web pages of API documentation.

Downloading and Running LNIclient

LNIclient.java  

To use this class in your application, you will also need the following
Java libraries on your classpath:

1. Apache Jakarta Commons HTTPClient version 3
2. Apache Commons Codec (required by HTTPClient)
3. Apache Commons Logging (required by HTTPClient)
4. Apache Commons CLI

NOTE: Some of these libraries are also required by DSpace 1.4 and 1.5, so they
should be available in the lib subdirectory of your DSpace
runtime installation. HTTPClient is the execption.

Future Work

As mentioned, this is completely unsupported code.
You are encouraged to use it, improve upon it, and use the Wiki
to document and share your improvements.

Some useful extensions that could be added:

• Implement GET of a Bitstream
• Add methods and command-line options to do PROPFIND and access results.

If you find this documentation lacking, please add the missing answers
to it.