Redis实现简单文章投票

鉴于Redis被鹅厂一面二面问过的原因

还是要好好学习一下

《Redis实战》第一章的例子

实现的功能

1）给文章投票

def article_vote(conn,user,article):
	cutoff=time.time()-ONE_WEEK_IN_SECONDS
	if conn.zscore('time:',article)<cutoff:
		return
	article_id=article.partition(':')[-1]
	
	if conn.sadd('voted:'+article_id,user):
		conn.zincrby('score:',article,VOTE_SCORE)
		conn.hincrby(article,'votes',1)

2）发布一个文章

def post_article(conn,user,title,link):
	article_id=str(conn.incr('article:'))
	voted='voted:'+article_id
	conn.sadd(voted,user)
	conn.expire(voted,ONE_WEEK_IN_SECONDS)
	now=time.time()
	article='article:'+article_id
	conn.hmset(article,{'title':title,'link':link,'poster':user,'time':now,'votes':1})
	conn.zadd('score:',article,now+VOTE_SCORE)
	conn.zadd('time:',article,now)
	return article_id

3）获取文章列表

ARTICLES_PER_PAGE = 25
def get_articles(conn,page,order='score:'):
	start=(page-1)*ARTICLES_PER_PAGE
	end=start+ARTICLES_PER_PAGE-1
	ids=conn.zrevrange(order,start,end)
	articles=[]
	for id in ids:
		article_data=conn.hgetall(id)
		article_data['id']=id
		articles.append(article_data)
	return articles

4）文章更改分组

def add_remove_groups(conn,article_id,to_add=[],to_remove=[]):
	article='article:'+article_id
	for group in to_add:
		conn.sadd('group:'+group,article)
	for group in to_remove:
		conn.srem('group:'+group,article)

5）获取某分组文章

def get_group_articles(conn,group,page,order='score:'):
	key=order+group
	if not conn.exists(key):
		conn.zinterstore(key,['group:'+group,order],aggregate='max',)
		conn.expire(key,60)
	return get_articles(conn,page,key)

测试代码

class TestCh01(unittest.TestCase):
    def setUp(self):
        import redis
        self.conn = redis.Redis(db=15)

    def tearDown(self):
        del self.conn
        print
        print

    def test_article_functionality(self):
        conn = self.conn
        import pprint

        article_id = str(post_article(conn, 'username', 'A title', 'http://www.google.com'))
        print "We posted a new article with id:", article_id
        print
        self.assertTrue(article_id)

        print "Its HASH looks like:"
        r = conn.hgetall('article:' + article_id)
        print r
        print
        self.assertTrue(r)

        article_vote(conn, 'other_user', 'article:' + article_id)
        print "We voted for the article, it now has votes:",
        v = int(conn.hget('article:' + article_id, 'votes'))
        print v
        print
        self.assertTrue(v > 1)

        print "The currently highest-scoring articles are:"
        articles = get_articles(conn, 1)
        pprint.pprint(articles)
        print

        self.assertTrue(len(articles) >= 1)

        add_remove_groups(conn, article_id, ['new-group'])
        print "We added the article to a new group, other articles include:"
        articles = get_group_articles(conn, 'new-group', 1)
        pprint.pprint(articles)
        print
        self.assertTrue(len(articles) >= 1)

        to_del = (
            conn.keys('time:*') + conn.keys('voted:*') + conn.keys('score:*') + 
            conn.keys('article:*') + conn.keys('group:*')
        )
        if to_del:
            conn.delete(*to_del)

if __name__ == '__main__':
    unittest.main()

可以看出

Python连接Redis 和PHP连接MySQL差不多啊，都是要用conn那个连接，然后执行Redis语句即可