class CRDTStore:
def __init__(self,
server=None,
user_id=0,
initial_version=None,
initial={}):
self.state = initial
self.initial_state = initial
self.history = History()
self.user_id = user_id
self.version = VectorClock(user_id, initial_version)
self.server = server
if server is not None:
self.server.on_recieve += self.on_recieve
self.on_update = Callback()
def on_recieve(self, op: Op):
# merge
self.merge(op)
def merge(self, op: Op):
# TODO: ignore duplicates?
# update version
self.version.merge(op.id)
# apply and store history
self.state = op.apply(self.state)
self.history.append(op)
self.on_update()
def apply(self, op: Op):
# merge op
self.merge(op)
# send op to clients
if self.server is not None:
self.server.send(op)
def get(self, field: str):
if field in self.state:
return self.state[field][1] # TODO: check if tombstoned
return None
