def zadd(self, key, score, value, nx=False, xx=False):
zset_length = int(self._db.get(KEY_CODEC.encode_zset(key), '0'))
batch = self._db.write_batch()
db_score = self._db.get(KEY_CODEC.encode_zset_value(key, value))
if db_score is not None:
if nx:
return 0
result = 0
previous_score = db_score
if float(previous_score) == float(score):
return result
else:
batch.delete(
KEY_CODEC.encode_zset_score(key, value, previous_score))
else:
if xx:
return 0
result = 1
zset_length += 1
batch.put(KEY_CODEC.encode_zset(key), bytes(zset_length))
batch.put(KEY_CODEC.encode_zset_value(key, value),
to_float_string(score))
batch.put(KEY_CODEC.encode_zset_score(key, value, score), bytes(''))
batch.write()
return result
def zrem(self, key, *members):
"""
see zadd() for information about score and value structures
"""
result = 0
zset_length = int(self._db.get(KEY_CODEC.encode_zset(key), '0'))
# safe guard
if zset_length == 0:
return result
batch = self._db.write_batch()
for member in members:
score = self._db.get(KEY_CODEC.encode_zset_value(key, member))
if score is None:
continue
result += 1
zset_length -= 1
batch.delete(KEY_CODEC.encode_zset_value(key, member))
batch.delete(KEY_CODEC.encode_zset_score(key, member, score))
# empty zset should be removed from keyspace
if zset_length == 0:
self.delete(key)
else:
batch.put(KEY_CODEC.encode_zset(key), bytes(zset_length))
batch.write()
return result
