A step-by-step guide helping you to publish your data as Linked Data using the LMF

This guide gives you step-by-step instructions on how to publish existing data as Linked Data through the LMF. Out of the many different approaches that are possible, we have selected some of the most common, namely:

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Publishing Linked Data in 5 Steps

For the impatient, if you have used the LMF Standalone Installer for installing the LMF, this section tells you how to publish Linked Data from legacy data in 5 steps:

1. [[Module Stanbol|Install Stanbol Referenced Sites]] you want to use for reconciliation (e.g. DBPedia, MusicBrainz, eHealth)
2. [[Google Refine Users Documentation|Import Data into Google Refine]] (accessible at http://your.host.name:8080/refine/)
3. Reconcile the columns you would consider relevant
4. Edit your RDF Skeleton for mapping the columns with your desirable vocabularies/ontologies terms, creating the pertinent links with the reconciled entities from the previous step
5. Save your data into LMF using the LMF menu in Refine

Now your resources are instantly available as Linked Data, so you can access them using their URIs. One convenience way to do this would be to access the RDF Skeleton preview, where the URIs are clickable.

Publishing Existing RDF Data

The most simple way to publish data as Linked Data through the LMF is when you already have your data prepared as RDF (in any of the formats RDF/XML, N3, Turtle, NTriples or JSNON-LD). In this case, the LMF offers a simple upload/import mechanism where you can directly upload the RDF files. The service can be used in three ways: 1. Going to the admin web interface (e.g. http://your.host.name:8080/LMF), selecting the Core Module, where you can find the Import submenu. There you can fulfill all the necessary details (file, format, etc) for importing your data into LMF. Resources are then instantly available as Linked Data (see[[Usage Resource Interaction|examples]] how to access them). 1. Accessing directly to the RESTfull web services directly, as described. 1. Using the [[Client Library|client library]] provided in your more convenience language or even the [[Shell Client Library|shell client library]].

Note that the LMF import mechanism will import the RDF data "as-is", i.e. it will not rewrite resource URIs or do any other transformation. This means that it is necessary that you already use the correct Linked Data URIs in your RDF file. For example, assuming your LMF server is accessible under http://your.host.name:8080/LMF/, then your resources should use it as base URI; if they do not, the resources will still be accessible, but they are considered "external resources" that are not available through the standard Linked Data principles ( [[Usage External Resources|see more information about external resources]]).

Publishing Legacy Data

Publishing legacy data ("triplification") is more difficult than publishing existing RDF data, since it requires mapping existing structures into structures compatible with the RDF graph model.

There are the following possible approaches:

• Reuse an existing RDFizer
• Write a custom LMF Importer for the data
• Use the [[Client Library|LMF Client Library]] to create/update data in the LMF from a legacy application
• User a more generic tool, for instance Google Refine RDF Extension or D2RQ Server, for a more customized data lifting process.

That last option if what would be describe in much more detail below.

Using Google Refine and the RDF Extension in LMF

A very convenient way that guides you through all steps of Linked Data Publishing is to use Google Refine and the RDF Extension to clean up and transform your data, and then LMF to publish it. The following screencast illustrates the process on a simple example where you manually installed all the required tools:

<wiki:video url="http://www.youtube.com/watch?v=_3BmNcHW4Ew" width="640" height="360">

For those who have used a modern version of the LMF installer (>=2.2.0), the process is even easier, since now it provides an integrated tool suite bundled together, including:

**Linked Media Framework**

[http://your.host.name:8080/LMF/](http://localhost:8080/LMF/)

**[Apache Stanbol](http://incubator.apache.org/stanbol/)**

[http://your.host.name:8080/stanbol/](http://localhost:8080/stanbol/)

**[Google Refine](http://google-refine.googlecode.com)**

with the [RDF](http://lab.linkeddata.deri.ie/2010/grefine-rdf-extension/) and [[Google Refine Extension|LMF]] extensions already installed

[http://your.host.name:8080/refine/](http://localhost:8080/refine/)

This integrated tool suite allows you some more advanced services:

• Enhance with Stanbol your content
• Perform an effective reconciliation in Refine using Stanbol
• Save directly your data into LMF

Summarizing, you can take your legacy data, parse it, manipulate it, enhance it, interlink with external data source of the Linked Data Cloud, store it and get it published as Linked Data using an integrated graphical user interface.