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Java

Create a Nanopublication

Prerequisite for creating/publishing

To create and publish nanopublications, you need to first make sure you have a local keypair. To create such a keypair, run just once: 

MakeKeys.make("~/.nanopub/id", SignatureAlgorithm.RSA);


NanopubCreator npCreator = new NanopubCreator(true);
final ValueFactory vf = SimpleValueFactory.getInstance();
final IRI anne = vf.createIRI("https://example.com/anne");
npCreator.addAssertionStatement(anne, RDF.TYPE, vf.createIRI("https://schema.org/Person"));
npCreator.addProvenanceStatement(PROV.WAS_ATTRIBUTED_TO, anne);
npCreator.addPubinfoStatement(RDF.TYPE, vf.createIRI("http://purl.org/nanopub/x/ExampleNanopub"));
Nanopub np = npCreator.finalizeNanopub(true);

Sign a Nanopublication

Prerequisite for signing/publishing

Before you can sign and publish you should setup your profile, check if it is properly set by running np profile in your terminal.

Nanopub signedNp = SignNanopub.signAndTransform(np, TransformContext.makeDefault());

Publish a Nanopublication

Prerequisite for creating/publishing

To create and publish nanopublications, you need to first make sure you have a local keypair. To create such a keypair, run just once: 

MakeKeys.make("~/.nanopub/id", SignatureAlgorithm.RSA);

Publish to the Test Server

PublishNanopub.publishToTestServer(signedNp);

Publish to the Production Server

PublishNanopub.publish(signedNp);

Verification of unpublished Nanopublications

Besides strict syntactical requirements a nanopub has to fulfill to be published there are a bunch of best practices, which should be honored. With the command line tool you can use 

np check myNanopub.trig -v

to see a list of issues. To ensure you only publish nanopubs that meet all best practices use the flag --strict when publishing:

np publish --strict myNanopub.trig -v

In the java API you can use 

NanopubVerifier verifier = new NanopubVerifier(nanopub);
verifier.verify();
verifier.getIssues();

Best Practices

The best practices that are verified are the following:

  • The creation timestamp of the nanopub is not in the future and not older than one hour.
  • The nanopub has a label.
  • The nanopub has a type.
  • The nanopub uses an assertion template and a provenance template.
  • The nanopub has a signer and the signer is also a creator of the nanopub.
  • The nanopub contains the graph uris: …Head, …assertion, …provenance, and …pubinfo.
  • The nanopub consists of below than 1200 triples and is smaller than 10MB.