From v2009.1, it is possible to sign on using a MyProxy service instead of a community accounts service. "Signing on at a MyProxy service" means that the library does a GET operation on the service, authenticating with the given password and obtaining a certificate chain tipped with a proxy certificate. The proxy certificate must be put into MyProxy beforehand using the latter's normal mechanisms.
To sign on at a MyProxy service, pass an approriate credential-source URI to SecurityGuard.signOn(String, String, int, URI). The URI may be in the myproxy scheme or the ivo scheme.
If you pass a URI in the form myproxy://address:port, then the library will use the service at that address and port. Port 7512 is normal, but the library does not use this default; you must state the port explicitly.
If you pass a URI of the form ivo://authority/resource-key - i.e. an IVOA identifier - then the library will look up that resource in the IVOA registry and will use whatever service capabilities it finds there. If it finds a community accounts capability then it will use that. If it does not find the accounts capability but instead finds a MyProxy capability then it will sign on at the MyProxy service.
The capability for registering a MyProxy service is expected to be a plain capability with no extra metadata beyond those allowed by VOResource 1.0. It must have the standard ID ivo://ivoa.net/std/MyProxy. There should be one interface, in which the access URL should be of the form described above.
MyProxy has no mechanism to record and communicate the location of a user's home-space in VOSpace. If a user is signed on at a MyProxy service, then SecurityGuard.getHomespaceLocation() and SecurityGuard.getHomespaceLocationAsString() return null.
MyProxy supports changes of the password protecting a user's credentials. The facade library tries to implement this but there is currently a bug: password changes always fail. We hope to fix this in a later release.
The security facade has no support for putting a proxy certificate into a MyProxy service, or for putting an EEC into the service. These features might be added in a later release, but only if there is a strong demand.