Linked Data Fragments
A linked data fragment which takes an arbitrary subject and returns a cached result.
Configuration
YAML
You need a ldf.yml file configured. There are currently two sample files for configurations of two different backend caching layers: ldf.yml.sample_marmotta and ldf.yml.sample_repository.
Marmotta
If you do not already have a marmotta instance, you can use an instance that runs off of jetty by running the following rake task:
rake ldfjetty:install
Once that finishes, please copy config/jetty.yml.sample to config/jetty.yml. You can change the defaults.
Once that is all setup, here are some commands that can be run to use the marmotta instance:
rake ldfjetty:stop
rake ldfjetty:config
rake ldfjetty:start
Blazegraph
If you do not already have a blazegraph instance, you can use an instance that runs off of jetty by running the following rake task:
rake ldfjetty:install
Once that finishes, please copy config/ldfjetty.yml.sample to config/ldfjetty.yml. You can change the defaults.
It is recommended that you populate Blazegraph with LoC for terms to work. To do this:
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Download the latest subjects vocab from: http://id.loc.gov/download/ (the nt version of “LC Subject Headings (SKOS/RDF only)”)
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Extract the above download into a directory.
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Run the following command from that extraction directory: curl -H 'Content-Type: text/turtle' --upload-file subjects-skos-20140306.nt -X POST "http://localhost:8988/blazegraph/sparql?context-uri=http://id.loc.gov/static/data/authoritiessubjects.nt.skos.zip"
Once that is all setup, here are some commands that can be run to use the blazegraph instance:
rake ldfjetty:stop
rake ldfjetty:config
rake ldfjetty:start
Usage
Dataset Response
In the default config, this is http://localhost:3000?format=jsonld
Resolving a subject uri
In the default config, this would be something like http://localhost:3000/http://dbpedia.org/resource/Berlin?format=jsonld assuming that you have marmotta running and that linked data source configured in marmotta.