# This works with Kuma's memcache implementation
from django.core.cache import caches

def clear_keys(prefix):
    memcache = caches['memcache']
    raw_memcache = memcache._cache
    items = 100000
    slabs = raw_memcache.get_stats('slabs')
    max_slabs = max([int(report[1]['active_slabs']) for report in slabs])
    deleted = 0
    for slab in range(max_slabs + 1):
        cachedump = raw_memcache.get_stats('cachedump %d %d' % (slab, items))
        for server, item_dict in cachedump:
            for key, meta in item_dict.items():
                if key.startswith(prefix):
                    memcache.delete(key)
                    deleted += 1
    return deleted