VOSpace delegate notes

These notes refer to the as yet unreleased version 2009.0.01.alpha version of the VOSpace client.

The main client side intefaces and classes are

• SystemDelegate
• SystemDelegateResolver
• SystemDelegateResolverImpl

Top level VOSpace delegate

To create a new Node within VOSpace, use one of the create methods on SystemDelegate .

The create methods themselves are inherited from the common delegate interface AbstractDelegate .

    interface SystemDelegate
    extends AbstractDelegate
        {
    
        public Node create(NodeTypeEnum type, URI uri)
        throws ... ;

        }

The SystemDelegate is the top level delegate that provides access to the VOSpace system, spanning multiple VOSpace services.

• It will automatically resolve VOSpace links that point to other VOSpace services.
• It will automatically handle retries using alternative endpoints if a VOSpace service is registered with more than one endpoint.

Using default registry client

If you want to use the default AG registry delegate.

    import java.net.URI;
    import org.astrogrid.security.SecurityGuard;
    import org.astrogrid.vospace.v11.client.node.Node;
    import org.astrogrid.vospace.v11.client.node.NodeTypeEnum;
    import org.astrogrid.vospace.v11.client.system.SystemDelegate;
    import org.astrogrid.vospace.v11.client.system.SystemDelegateResolver;
    import org.astrogrid.vospace.v11.client.system.SystemDelegateResolverImpl;

    //
    // Generate user name ....
    String username = "albert" ;

    //
    // Load the user credentials ....
    SecurityGuard guard = ....

    //
    // Create the new URI.
    final URI baseuri = new URI(
        "vos://service/base/"
        );
    final URI useruri = base.resolve(
        username
        );

    //
    // Create a VOSpace delegate resolver (using the default AG Registry client).
    final SystemDelegateResolver resolver = new SystemDelegateResolverImpl()

    //
    // Create a VOSpace delegate (using the SecurityGuard credentials).
    final SystemDelegate delegate = resolver.resolve(
        guard
        );

    //
    // Create the VOSpace node.
    final Node node = delegate.create(
        NodeTypeEnum.TREE_NODE,
        useruri
        );

    log.debug("Node created");
    log.debug("  URI  [" + node.uri()  + "]");
    log.debug("  Type [" + node.type() + "]");
    log.debug("  Name [" + node.name() + "]");
    log.debug("  Path [" + node.path() + "]");

Using custom registry client

If you want to manage your own registry delegates, then you can pass it in to the resolver constructor.

    import org.astrogrid.registry.client.query.v1_0.RegistryService;

    //
    // Our registry delegate.
    RegistryService registry = ....
        
    //
    // Create a VOSpace delegate resolver (using a custom registry client).
    final SystemDelegateResolver resolver = new SystemDelegateResolverImpl(
        registry
        );

Server generated name

If you want the VOSpace server to allocate a unique name for the node, then use '.auto' in the Node URI.

    //
    // Create the new URI.
    final URI baseuri = new URI(
        "vos://service/base/"
        );
    final URI useruri = base.resolve(
        ".auto"
        );

JUnit examples

Further examples of how the deledate and resolver are used are available in the JUnit tests.

• SystemDelegateTestCase

Maven dependencies

Direct dependencies

• The VOSpace common tools
  • astrogrid-vospace-util-2009.0.01.alpha

• The VOSpace 1.1 schema beans.
  • astrogrid-vospace-1.1-schema-2009.0.01.alpha

• The VOSpace 1.1 client components.
  • astrogrid-vospace-1.1-client-2009.0.01.alpha

Additional dependencies

• Apache Axis 1.2.1
• AstroGrid security
• AstroGrid astrogrid-common
• AstroGrid astrogrid-registry-common
• AstroGrid astrogrid-registry-client-lite

-- DaveMorris - 14 Apr 2009