Bulk remove on IDistributedCache

[ehabelgindy]

Would it be useful if the IDistibutedCache interface can allow bulk remove?

Unlike the memory cache, removing multiple entries from distributed caches can be an expensive task. Providing an overload of the Remove function that accept an array of keys - e.g. Task Remove(string [] keys) - would allow more efficient implementations of distributed caches.

[RehanSaeed]

I posted an IDistributedCache helper which clears the cache and also bulk removes keys here, just in case someone finds it useful.

[SimonOrdo]

@RehanSaeed It looks like you're missing IDistributedCacheExtended definition in your post.

[eerhardt]

We've reached feature complete for .NET 6. Moving to 7.

[deeprobin]

MemoryCache already implements this (see #45593). I think we can tag this as api-suggestion. However, this API would also be a breaking-change, due to other non-BCL implementations of the interface.

Here my proposal:

namespace Microsoft.Extensions.Caching.Distributed
{
    public interface IDistributedCache
    {
        void Clear();
        // Maybe, a ValueTask would not be a bad idea, but other Async APIs use a normal Task in this class.
        Task ClearAsync(CancellationToken cancellationToken = default);
    }

    public partial class MemoryDistributedCache : IDistributedCache {
        public void Clear();
        public Task ClearAsync(CancellationToken cancellationToken = default);
    }
}

namespace Microsoft.Extensions.Caching.Redis
{
    public partial class RedisCache : IDisposable, IDistributedCache {
        public void Clear();
        public Task ClearAsync(CancellationToken cancellationToken = default);
    }
}

namespace Microsoft.Extensions.Caching.StackExchangeRedis
{
    public partial class RedisCache : IDisposable, IDistributedCache {
        public void Clear();
        public Task ClearAsync(CancellationToken cancellationToken = default);
    }
}

namespace Microsoft.Extensions.Caching.SqlServer
{
    public partial class SqlServerCache : IDistributedCache {
        public void Clear();
        public Task ClearAsync(CancellationToken cancellationToken = default);
    }
}

[deeprobin]

• The interface can't be changed, per our breaking change rules.

Originally posted by @bartonjs in #45593 (comment)

It would probably make sense to update only the implementations and not change the interface due to the breaking change.

[eerhardt]

We have started using Default Interface Members (DIMs) in Microsoft.Extensions. This may be a candidate to add in .NET 6.0+ APIs just like we did for #66479.

Here my proposal:

I don't believe the original intention of this issue is to remove all the entries from the cache, but remove a set of them specified by a collection of keys.