Python redis

Connect

集群

# pip3 install redis-py-cluster

import rediscluster
rnode = [
    {"host": "192.168.0.229", "port": 6379},
    {"host": "192.168.0.229", "port": 6380},
    {"host": "192.168.0.148", "port": 6379},
    {"host": "192.168.0.148", "port": 6380},
    {"host": "192.168.0.249", "port": 6379},
    {"host": "192.168.0.249", "port": 6380}
]

# decode_responses=True，返回值字符串（否则为 byte)
rc = rediscluster.RedisCluster(startup_nodes=rnode, decode_responses=True)

单机

Redis 的单机使用在集群上时，如果读的数据不在连接主机上，会出现错误。

# pip3 install redis
import redis
rc = redis.Redis(host='192.168.0.229', port=6379, db=0)

操作

Connection Pool

使用连接池来管理所有连接，避免每次建立、释放连接的开销。

# redis
rcp = redis.ConnectionPool(host='192.168.0.229', port=6379, db=0)
rc = redis.Redis(connection_pool = rcp, decode_responses=True)
rc2 = redis.Redis(connection_pool = rcp, decode_responses=True)
# redis cluster
rcp = rediscluster.ClusterConnectionPool(startup_nodes=rnode, decode_responses=True)
rc = rediscluster.RedisCluster(connection_pool=rcp)

管道

Redis 管道技术可以在服务端未响应时，客户端可以继续向服务端发送请求，并最终一次性读取所有服务端的响应。批量写入时,使用pipeline可以大幅度提升性能

# 使用 rp 代替 rc
rp = rc.pipeline(transaction = False)
# 足够数量的 rp.set 后，提交
FLAG = rp.execute()

set

rc.set('test', 'Hello, World!')
rc.set('test1', 'Hello, Redis!')
rc.set('test2', 'Hello, RDS!')

get

rc.get('test')

keys

rc.keys('*test*')
rc.keys('*test?')

scan

rc.scan(0, '*0123*', 10)
{'192.168.0.229:6379': (6292935, ['86.56789.410/154710123', '86.56789.410/117012344']), '192.168.0.148:6379': (2099409, ['86.56789.410/121501232', '86.56789.410/110123399']), '192.168.0.249:6379': (6293256, ['86.56789.410/129012348', '86.56789.410/199530123'])}

delete

rc.delete('test2')

各节点记录数

rc.dbsize()

有效时间

100 secs

# rc.set('test', 'Hello, World!', 100)
rc.set('test', 'Hello, World!')
rc.expire('test', 100)
rc.get('test')