Namespaces support - Githubissues

Problem:
==========================
1. Currently Objectify (v4) is completely unaware of namespaces (Datastore 
feature that allows multitenancy) 
2. Modern apps using multitenancy typically switch namespaces very often.
3. And it looks like this:

        final String namespace = NamespaceManager.get();
        try {
            NamespaceManager.set(null);
            return ofy.get().load().....// do work here
        } finally {
            NamespaceManager.set(namespace);
        }
4. Or like this: 

public final class OfyUtils {

    private OfyUtils() {}

    public static void safeWork(String namespace, VoidWork work){
        final String original = NamespaceUtils.get();
        try {
            NamespaceUtils.set(namespace);
            work.run();
        } finally {
            NamespaceUtils.set(original);
        }
    }

}

        OfyUtils.safeWork(namespace, new VoidWork(){
            @Override
            public void vrun() {
                // do work here
            }
        });

Enhancements:
=========================================================

5. It would be nice to be able to write only
ofy.get().namespace("customer1").load()....
ofy.get().namespace(null/*no ns*/).transact(....

6. Annotation on entities @Namespace(required=true || value="hasrdcodedNS")
Features: 
1. Automatic checking that namesapce is set if attrib. required == true
2. Automatic switching of namespace if hardcoded in annotation

Notes:
=================
Its not possible to implement something like:
Clazz cz = OfyUtils.namespace("customer1", 
ofy.get().load().type(clazz).id("cz1")).now() 

OFY api currently lacks possibility to twiddle with the query builder objects!

Btw: Objectify is very cool:) I love it.
Original issue reported on code.google.com by jan.g...@gmail.com on 12 Apr 2014 at 4:08
google-code-export / objectify-appengine

Namespaces support #194
