def test_gcounter():
"""
[]
/ \
A[a:1] B[b:1] +1, +1
| | \
| | \
| / |
AB[a:1, b:1] | merge
| |
AB[a:2, b:1] | +1
| |
\ B2[b:2] +1
\ |
\ /
ABB2[a:2, b:2] merge
"""
A = GCounter(client_id="a")
B = GCounter(client_id="b")
A.increment()
assert A.payload == {"a": 1}
B.increment()
assert B.payload == {"b": 1}
B2 = B.clone()
assert B2.payload == {"b": 1}
B2.increment()
assert B2.payload == {"b": 2}
AB = GCounter.merge(A, B)
AB.client_id = "a"
assert AB.payload == {"a": 1, "b": 1}
AB.increment()
assert AB.payload == {"a": 2, "b": 1}
ABB2 = GCounter.merge(AB, B2)
assert ABB2.payload == {"a": 2, "b": 2}
def test_gcounter():
"""
[]
/ \
A[a:1] B[b:1] +1, +1
| | \
| | \
| / |
AB[a:1, b:1] | merge
| |
AB[a:2, b:1] | +1
| |
\ B2[b:2] +1
\ |
\ /
ABB2[a:2, b:2] merge
"""
A = GCounter(client_id="a")
B = GCounter(client_id="b")
A.increment()
assert A.payload == {"a": 1}
B.increment()
assert B.payload == {"b": 1}
B2 = B.clone()
assert B2.payload == {"b": 1}
B2.increment()
assert B2.payload == {"b": 2}
AB = GCounter.merge(A, B)
AB.client_id = "a"
assert AB.payload == {"a": 1, "b": 1}
AB.increment()
assert AB.payload == {"a": 2, "b": 1}
ABB2 = GCounter.merge(AB, B2)
assert ABB2.payload == {"a": 2, "b": 2}
def __init__(self, client_id=None):
self.P = GCounter()
self.N = GCounter()
self.client_id = client_id or random_client_id()
class PNCounter(StateCRDT):
def __init__(self, client_id=None):
self.P = GCounter()
self.N = GCounter()
self.client_id = client_id or random_client_id()
#
# State-based CRDT API
#
def get_payload(self):
return {"P": self.P.payload, "N": self.N.payload}
def set_payload(self, payload):
self.P.payload = payload['P']
self.N.payload = payload['N']
payload = property(get_payload, set_payload)
def get_client_id(self):
return self._cid
def set_client_id(self, client_id):
self._cid = client_id
self.P.client_id = client_id
self.N.client_id = client_id
client_id = property(get_client_id, set_client_id)
def clone(self):
new = super(PNCounter, self).clone()
# Copy the client id
new.client_id = self.client_id
return new
@property
def value(self):
return self.P.value - self.N.value
@classmethod
def merge(cls, X, Y):
merged_P = GCounter.merge(X.P, Y.P)
merged_N = GCounter.merge(X.N, Y.N)
merged_payload = {
"P": merged_P.payload,
"N": merged_N.payload,
}
return PNCounter.from_payload(merged_payload)
def compare(self, other):
"""
(∀i ∈ [0, n − 1] : X.P [i] ≤ Y.P [i] ∧
∀i ∈ [0, n − 1] : X.N[i] ≤ Y.N[i]
"""
P_compare = self.P.compare(other.P)
N_compare = self.N.compare(other.N)
return P_compare and N_compare
#
# Counter API
#
def increment(self):
self.P.increment()
def decrement(self):
self.N.increment()
def __cmp__(self, other):
return self.value.__cmp__(other.value)
def __init__(self, client_id=None):
self.P = GCounter()
self.N = GCounter()
self.client_id = client_id or random_client_id()
class PNCounter(StateCRDT):
def __init__(self, client_id=None):
self.P = GCounter()
self.N = GCounter()
self.client_id = client_id or random_client_id()
#
# State-based CRDT API
#
def get_payload(self):
return {
"P": self.P.payload,
"N": self.N.payload
}
def set_payload(self, payload):
self.P.payload = payload['P']
self.N.payload = payload['N']
payload = property(get_payload, set_payload)
def get_client_id(self):
return self._cid
def set_client_id(self, client_id):
self._cid = client_id
self.P.client_id = client_id
self.N.client_id = client_id
client_id = property(get_client_id, set_client_id)
def clone(self):
new = super(PNCounter, self).clone()
# Copy the client id
new.client_id = self.client_id
return new
@property
def value(self):
return self.P.value - self.N.value
@classmethod
def merge(cls, X, Y):
merged_P = GCounter.merge(X.P, Y.P)
merged_N = GCounter.merge(X.N, Y.N)
merged_payload = {
"P": merged_P.payload,
"N": merged_N.payload,
}
return PNCounter.from_payload(merged_payload)
def compare(self, other):
"""
(∀i ∈ [0, n − 1] : X.P [i] ≤ Y.P [i] ∧
∀i ∈ [0, n − 1] : X.N[i] ≤ Y.N[i]
"""
P_compare = self.P.compare(other.P)
N_compare = self.N.compare(other.N)
return P_compare and N_compare
#
# Counter API
#
def increment(self):
self.P.increment()
def decrement(self):
self.N.increment()
def __cmp__(self, other):
return self.value.__cmp__(other.value)
