def test_read_conflict_rollback_not_reintroduced():
db = StubDb()
rollback = StubRollback()
qa = qube.init({'test': set()})
qb = qube.init({'test': set()})
qube.apply_op(qa, ('add', 'test', 'abc', 'tx0'))
qube.apply_op(qa, ('rem', 'test', 'abc', 'tx456'))
qube.apply_op(qb, ('add', 'test', 'abc', 'tx0'))
qube.apply_op(qb, ('rem', 'test', 'abc', 'tx456'))
qube.rollback(qa, 'tx456')
qube.apply_op(qa, ('add', 'test', 'def', 'tx789'))
qube.apply_op(qb, ('add', 'test', 'ghi', 'tx321'))
def doraise(a, b):
raise riak.Conflict('the_vclock',
'x/zzz',
[StubDbResult(qube.to_json(qa)),
StubDbResult(qube.to_json(qb))])
db.get.side_effect = doraise
m = yield from FooModel.read(db, rollback, 'zzz')
assert_that(m.qube['journal'], has_length(3))
assert_that(m.qube['data'], has_entry('test', {'abc', 'def', 'ghi'}))
assert_that(db.save, called_once_with('foo_bucket',
'zzz',
has_key('data')))
def read(cls, db, rollback, key):
logger.debug("reading %s/%s", cls.bucket, key)
modified = False
rollbacks = rollback.txs
@contextlib.contextmanager
def queue_rollback(op):
try:
yield
except Exception as e:
logger.debug('operation failed %r', op)
cls.queue_rollback(rollback, op)
try:
response = yield from db.get(cls.bucket, key)
except riak.Conflict as e:
logger.debug("conflict in %s/%s", cls.bucket, key)
modified = True
first = e.siblings.pop()
links = first.links
vclock = e.vclock
data = qube.from_json(first)
for tx in rollbacks:
qube.rollback(data, tx, error=queue_rollback)
for r in e.siblings:
r = qube.from_json(r)
for tx in rollbacks:
qube.rollback(r, tx, error=queue_rollback)
data = qube.merge(data, r, error=queue_rollback)
except:
logger.error("Other error reading", exc_info=True)
raise
else:
links = response.links
vclock = response.vclock
data = qube.from_json(response)
if rollbacks:
logger.debug("processing rollbacks in %s/%s %r", cls.bucket, key, rollbacks)
try:
seq = data['sequence']
for tx in rollbacks:
data = qube.rollback(data, tx, error=queue_rollback)
modified = seq != data['sequence']
except:
logger.error("error performing rollback", exc_info=True)
raise
model = cls(key, data, vclock=vclock, links=links)
if modified:
# Ideally this would happen after returning the list
# TODO: Task()
yield from model.save(db)
yield from rollback.process(db)
logger.debug('read %s/%s %s', cls.bucket, key, vclock)
return model
