@Test
public void readCustomProperty() throws Exception {

    List<Object> expandContext = ImmutableList.of(Bdio.Context.DEFAULT.toString(), ImmutableMap.of("foobar", "http://example.com/gus"));
    BdioMetadata metadata = BdioMetadata.createRandomUUID();
    Project projectModel = new Project(BdioObject.randomId());
    projectModel.put("http://example.com/gus", "testing");
    InputStream inputStream = BdioTest.zipJsonBytes(metadata.asNamedGraph(Lists.newArrayList(projectModel)));
    graph.io(testBdio(TT.unknown).context(null, expandContext)).readGraph(inputStream, null, null);
    Optional<Object> unknown = graph.traversal().V().hasLabel(Bdio.Class.Project.name()).values("_unknown").tryNext();
    assertThat(unknown).isEmpty();
    Optional<Object> foobar = graph.traversal().V().hasLabel(Bdio.Class.Project.name()).values("foobar").tryNext();
    assertThat(foobar).hasValue("testing");
}