Redis的Python实践，以及四中常用应用场景详解——学习董伟明老师的《Python Web开发实践》

# coding=utf-8
import string
import random

import redis

r = redis.StrictRedis(host=‘localhost‘, port=6379, db=0)
GAME_BOARD_KEY = ‘game.board‘

for _ in range(1000):
    score = round((random.random() * 100), 2)
    user_id = ‘‘.join(random.sample(string.ascii_letters, 6))
    #随机生成1000个用户，每个用户具有得分和用户名字，插入Redis的有序集合中
    r.zadd(GAME_BOARD_KEY, score, user_id)

# 随机获得一个用户和他的得分
user_id, score = r.zrevrange(GAME_BOARD_KEY, 0, -1,
                             withscores=True)[random.randint(0, 200)]
print (user_id, score)
#用有序集合的ZCOUNT获取0-100的个数也就是所有人的数量，获取0-score分数段的人数，也就是这个用户分数超过了多少人
board_count = r.zcount(GAME_BOARD_KEY, 0, 100)
current_count = r.zcount(GAME_BOARD_KEY, 0, score)

print (current_count, board_count)

print (‘TOP 10‘)
print (‘-‘ * 20)

#用有序集合的ZREVRANGEBYSCORE返回指定区间的元素
#ZREVRANGEBYSCORE key max min [WITHSCORES] [LIMIT offset count]
for user_id, score in r.zrevrangebyscore(GAME_BOARD_KEY, 100, 0, start=0,
                                         num=10, withscores=True):
    print (user_id, score)

# coding=utf-8
import time
import random
from datetime import datetime

import redis

r = redis.StrictRedis(host=‘localhost‘, port=6379, db=0)
ACCOUNT_ACTIVE_KEY = ‘account:active‘

r.flushall()
# r.delete(ACCOUNT_ACTIVE_KEY)
now = datetime.utcnow()


def record_active(account_id, t=None):
    #第一次t自己生成，后面t接受传入的年月日
    if t is None:
        t = datetime.utcnow()
    #Redis事务开始
    p = r.pipeline()
    key = ACCOUNT_ACTIVE_KEY
    #组合了年月日三种键值，同时将三个键值对应字符串的account_id位置为1
    #符合逻辑：该人在这一天登陆，肯定也在当前月登陆，也在当年登陆
    for arg in (‘year‘, ‘month‘, ‘day‘):
        key = ‘{}:{}‘.format(key, getattr(t, arg))
        p.setbit(key, account_id, 1)
    #Redis事务提交，真正执行
    p.execute()


def gen_records(max_days, population, k):
    #循环每天的情况，从1-max_days天
    for day in range(1, max_days):
        time_ = datetime(now.year, now.month, day)
        #每天随机生成k个数字，表示k个人活跃
        accounts = random.sample(range(population), k)
        #将这k个人对应在当天的字符串中修改，对应位置的bit置为1，表明这个天他有登陆过
        for account_id in accounts:
            record_active(account_id, time_)

#查看记录100万数据中随机选择10万活跃用户时的内存占用
def calc_memory():
    r.flushall()
    #执行前先看当前的内存占用
    print (‘USED_MEMORY: {}‘.format(r.info()[‘used_memory_human‘]))

    start = time.time()
    #100万种选择10万，20天
    gen_records(21, 1000000, 100000)
    #记录话费时间
    print (‘COST: {}‘.format(time.time() - start))
    #添加记录后的内存占用
    print (‘USED_MEMORY: {}‘.format(r.info()[‘used_memory_human‘]))

gen_records(29, 10000, 2000)
#这个月总的活跃用户数，直接查询记录月的key：bitcount "account:active:2016:11"
print (r.bitcount(‘{}:{}:{}‘.format(ACCOUNT_ACTIVE_KEY, now.year, now.month)))
#今天的活跃用户数：bitcount "account:active:2016:11:23"
print (r.bitcount(‘{}:{}:{}:{}‘.format(ACCOUNT_ACTIVE_KEY, now.year,
                                      now.month, now.day)))
#随机找一个account_id为1200的用户，查看他是否登陆过：getbit "account:active:2016:11" 1200
account_id = 1200
print (r.getbit(‘{}:{}:{}‘.format(ACCOUNT_ACTIVE_KEY, now.year, now.month),
               account_id))
#getbit "account:active:2016:11" 10001
print (r.getbit(‘{}:{}:{}‘.format(ACCOUNT_ACTIVE_KEY, now.year, now.month),
               10001))
#获取当月1号和2号的建
keys = [‘{}:{}:{}:{}‘.format(ACCOUNT_ACTIVE_KEY, now.year, now.month, day)
        for day in range(1, 3)]
#获取1号和2号的活跃的用户总数
r.bitop(‘or‘, ‘destkey:or‘, *keys)
print (r.bitcount(‘destkey:or‘))
#获取在1号和2号都活跃的用户数
r.bitop(‘and‘, ‘destkey:and‘, *keys)
print (r.bitcount(‘destkey:and‘))

9974
2000
1
0
3593
407

127.0.0.1:6379> bitcount "account:active:2016:11"
(integer) 9974
127.0.0.1:6379> bitcount "account:active:2016:11:23"
(integer) 2000
127.0.0.1:6379> getbit "account:active:2016:11" 1200
(integer) 1
127.0.0.1:6379> getbit "account:active:2016:11" 10001
(integer) 0
127.0.0.1:6379> bitop ‘or‘ ‘destkey:or‘ "account:active:2016:11:1","account:active:2016:11:2"
Invalid argument(s)
127.0.0.1:6379> bitop ‘or‘ ‘destkey:or‘ "account:active:2016:11:1" "account:active:2016:11:2"
(integer) 1250
127.0.0.1:6379> bitcount destkey:or
(integer) 3593
127.0.0.1:6379> bitop ‘and‘ ‘destkey:and‘ "account:active:2016:11:1" "account:active:2016:11:2"
(integer) 1250
127.0.0.1:6379> bitcount destkey:and
(integer) 407