How Sugar will interact with the DS for the May 17th demo in Argentina:

>>> from olpc.datastore import DataStore
>>> from olpc.datastore import backingstore
>>> ds = DataStore()
>>> ds.registerBackend(backingstore.FileBackingStore)
>>> assert ds.mount("/tmp/test_ds")


Create an entry without data:
>>> uid = ds.create(dict(title="New entry"), '')
>>> ds.complete_indexing()

>>> ds.get_filename(uid)
''

Update an entry without data:
>>> ds.update(uid, dict(title="New entry still without content"), '')

>>> ds.complete_indexing()

>>> ds.get_filename(uid)
''

Add some data to the same entry:
>>> fp = open('/tmp/sugar_ds_test', 'w')
>>> print >>fp, "some content"
>>> fp.close()
>>> ds.update(uid, dict(title="Same entry now with some content"), fp.name)
>>> ds.complete_indexing()

Retrieve that data:
>>> fn = ds.get_filename(uid)
>>> fp = open(fn, 'r')
>>> fp.read()
'some content\n'
>>> fp.close()

Update again:
>>> fp = open('/tmp/sugar_ds_test2', 'w')
>>> print >>fp, "some other content"
>>> fp.close()
>>> ds.update(uid, dict(title="Same entry with some other content"), fp.name)
>>> ds.complete_indexing()

And retrieve again:
>>> fn = ds.get_filename(uid)
>>> fp = open(fn, 'r')
>>> fp.read()
'some other content\n'
>>> fp.close()

Get all entries (only have one):
>>> results, count = ds.find({})
>>> results[0]['title']
'Same entry with some other content'

Check content:
>>> fn = ds.get_filename(uid)
>>> fp = open(fn, 'r')
>>> fp.read()
'some other content\n'
>>> fp.close()

Set content as pdf:
>>> ds.update(uid, dict(title="Same entry with some content in pdf"), 'test.pdf')
>>> ds.update(uid, dict(title="Same entry with some content in doc"), 'test.doc')
>>> ds.update(uid, dict(title="Same entry with some content in odt"), 'test.odt')
>>> ds.complete_indexing()

>>> ds.stop()
>>> del ds