ArtifactMetadata metadata = createArtifact();
Map<String, String> additionalProps = new HashMap<String, String>();
additionalProps.put( "deleteKey", "deleteValue" );
MetadataFacet facet = new TestMetadataFacet( TEST_FACET_ID, "baz", additionalProps );
metadata.addFacet( facet );
repository.updateArtifact( TEST_REPO_ID, TEST_NAMESPACE, TEST_PROJECT, TEST_PROJECT_VERSION, metadata );
Collection<ArtifactMetadata> artifacts =
repository.getArtifacts( TEST_REPO_ID, TEST_NAMESPACE, TEST_PROJECT, TEST_PROJECT_VERSION );