redis/redis-py · error · TypeError

Async Redis client does not support class deletion

Error message

Async Redis client does not support class deletion

What it means

Raised by AsyncBasicKeyCommands.__delitem__ (a TypeError) when you use 'del async_client[key]' on an async Redis client. The sync client maps del client[key] to DELETE, but the async client cannot because Python dunder methods cannot be async (awaitable), so the override raises immediately to prevent silent misuse.

Solutions

1. Replace 'del client[key]' with 'await client.delete(key)'.
2. If deleting multiple keys, use 'await client.delete(*keys)'.

Example fix

# before
del client['mykey']

# after
await client.delete('mykey')

# Never use del on an async client; call delete explicitly.
await client.delete(key)  # instead of del client[key]

import redis

def is_async_client(c) -> bool:
    return isinstance(c, (redis.asyncio.Redis, redis.asyncio.RedisCluster))

# usage: if is_async_client(client): await client.delete(key) else: del client[key]

try:
    del client[key]
except TypeError as e:
    if 'class deletion' in str(e):
        await client.delete(key)
    else:
        raise

When it happens

Trigger: Writing 'del redis_async[key]' or 'del redis_async['mykey']' where redis_async is a redis.asyncio.Redis instance. Code ported verbatim from the sync client that used item deletion.

Common situations: Migrating from redis.Redis to redis.asyncio.Redis and leaving dict-style deletion syntax in place. Code that generically calls __delitem__ on any mapping-like object.

Related errors

• Async Redis client does not support class assignment
• Async Redis client does not support class inclusion
• Async Redis client does not support class retrieval
• Bad response from PING health check
• Buffer is closed.

AI-assisted analysis of redis/redis-py@6a6b581b48 (2026-08-10). Data as JSON: /api/errors/5b706a8436470f00. Report an issue: GitHub.

Appendix: source

Thrown at redis/commands/core.py:4809

        the given ``minmatchlen``.
        If ``withmatchlen`` the length of the match also will be returned.
        For more information, see https://redis.io/commands/lcs
        """
        pieces: list[str | int] = [key1, key2]
        if len:
            pieces.append("LEN")
        if idx:
            pieces.append("IDX")
        if minmatchlen is not None and minmatchlen != 0:
            pieces.extend(["MINMATCHLEN", minmatchlen])
        if withmatchlen:
            pieces.append("WITHMATCHLEN")
        return self.execute_command("LCS", *pieces, keys=[key1, key2])


class AsyncBasicKeyCommands(BasicKeyCommands):
    def __delitem__(self, name: KeyT):
        raise TypeError("Async Redis client does not support class deletion")

    def __contains__(self, name: KeyT):
        raise TypeError("Async Redis client does not support class inclusion")

    def __getitem__(self, name: KeyT):
        raise TypeError("Async Redis client does not support class retrieval")

    def __setitem__(self, name: KeyT, value: EncodableT):
        raise TypeError("Async Redis client does not support class assignment")

    async def watch(self, *names: KeyT) -> None:
        return super().watch(*names)

    async def unwatch(self) -> None:
        return super().unwatch()


class ListCommands(CommandsProtocol):

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