redis-cluster.py

redis-cluster.py

import redis
from redis.exceptions import ResponseError

class RedisCluster:
    def __init__(self, *args, **kwargs):
        self._a = args
        self._kw = kwargs
        self._c = redis.Redis(*args, **kwargs)

    def shim(self, fn_getter, *args, **kwargs) -> any:
        try:
            fn = fn_getter(self._c)
            res = fn(*args, *kwargs)
            return res
        except ResponseError as r:
            e = str(r)
            if e.startswith('MOVED'):
                host, port = e.split(' ')[2].split(':')
                kw = {}
                kw.update(self._kw)
                kw['host'] = host
                kw['port'] = port
                self._c = redis.Redis(*self._a, **kw)
                return self.shim(fn_getter, *args, **kwargs)
            else:
                raise r

    def get(self, name) -> str:
        return self.shim(lambda x: x.get, name)