Stackexchange.redis: Asynchronous subscribe callback

I've considered this in the past, but ultimately: the library has no
interest in the continuation and has no need to await it. it doesn't care
about the result and can't do anything useful with an exception. I wonder
whether this is actually a case when an async void might be appropriate?
(These are few and far between)

On 2 Jun 2017 12:03 a.m., "BrennanConroy" notifications@github.com wrote:

Currently you can pass in an Action to Subscribe and SubscribeAsync
We would like to be able to pass in an asynchronous Action i.e. Func
callback that gets awaited in StackExchange.Redis.

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@mgravell For sequential subs, how do you pause the subscription without blocking a thread? The usual response is to offload to a queue, but the problem with that is if there are too many pending events to fit into a queue.

I think this is related to https://github.com/StackExchange/StackExchange.Redis/issues/281 https://github.com/FoundatioFx/Foundatio.Redis/blob/master/src/Foundatio.Redis/Messaging/RedisMessageBus.cs#L34-L49

I also have that same question. I'm changing our implementation back to async void as I feel like I could be contributing to thread pool exhaustion with the current GetAwaiter().GetResult(). Do you have any suggestions?

I'm marking as v2, not as a promise, but that we'll take a hard look at this along with the other API additions and changes.

The entire concept of an async task here only makes sense in the "everything in sequence" (PreserveAsyncOrder) scenario - in the "any order" scenario... meh, just use async void, nobody is waiting for you.

So; on the latter: this is implemented in v2; you need to use a slightly different API:

foo.Subscribe(key).OnMessage(handler);

The foo.Subscribe(key) here gives you a ChannelMessageQueue, which has OnMessage overloads for both synchronous (Action<RedisChannel, RedisValue>) and asynchronous (Func<RedisChannel, RedisValue, Task>) operations; in the latter case, it is awaited correctly for each operation.