lbzhao28 / zato-redis-paginator

Django-like Redis pagination for Python

Django-like Redis pagination for Python

Except for the _init_ method, this is 100% API compatible with Django's own pagination but works with Redis instead of SQL databases.

Supported data types:

• lists
• sorted sets
• ranges of sorted sets between min/max scores

The first two don't do it but the last one needs to fetch an entire result between min and max score to calculate the pages. This is because ZRANGEBYSCORE doesn't have any means to obtain the number of results that would've been returned without actually returning them.

Working with lists

Establishes a connection, creates a list and splits it into pages.

    from uuid import uuid4
    from redis import StrictRedis
    from zato.redis_paginator import ListPaginator
    
    conn = StrictRedis()
    key = 'paginator:{}'.format(uuid4().hex)
    
    for x in range(1, 18):
        conn.rpush(key, x)
        
    p = ListPaginator(conn, key, 6)
    
    print(p.count)      # 17
    print(p.num_pages)  # 3
    print(p.page_range) # [1, 2, 3]
    
    page = p.page(3)
    print(page)             # <Page 3 of 3>
    print(page.object_list) # ['13', '14', '15', '16', '17']
        
    conn.delete(key)

Working with sorted sets

Establishes a connection, creates a sorted set and splits it into pages.

    from uuid import uuid4
    from redis import StrictRedis
    from zato.redis_paginator import ZSetPaginator
    
    conn = StrictRedis()
    key = 'paginator:{}'.format(uuid4().hex)
    
    # 97-114 is 'a' to 'r' in ASCII
    for x in range(1, 18):
        conn.zadd(key, x, chr(96 + x))
        
    p = ZSetPaginator(conn, key, 6)
    
    print(p.count)      # 17
    print(p.num_pages)  # 3
    print(p.page_range) # [1, 2, 3]
    
    page = p.page(3)
    print(page)             # <Page 3 of 3>
    print(page.object_list) # ['m', 'n', 'o', 'p', 'q']
        
    conn.delete(key)

Working with sorted sets and min/max scores

Establishes a connection, creates a sorted set and splits it into pages while including only these members that are between min and max scores.

    from uuid import uuid4
    from redis import StrictRedis
    from zato.redis_paginator import ZSetPaginator
    
    conn = StrictRedis()
    key = 'paginator:{}'.format(uuid4().hex)
    
    # 97-114 is 'a' to 'r' in ASCII
    for x in range(1, 18):
        conn.zadd(key, x, chr(96 + x))
        
    p = ZSetPaginator(conn, key, 2, score_min=5, score_max=13)
    
    print(p.count)      # 9
    print(p.num_pages)  # 5
    print(p.page_range) # [1, 2, 3, 4, 5]
    
    page = p.page(3)
    print(page)             # <Page 3 of 5>
    print(page.object_list) # ['i', 'j']
        
    conn.delete(key)

Changelog

• Aug 11, 2013 - Initial 1.0 release

License

BSD 3-clause license, see LICENSE.txt for terms and conditions.

More information

Originally part of Zato - ESB, SOA and cloud integrations in Python - https://zato.io/docs/