Update Aspire template to use hybridcache instead of outputcache

[claudiaregio]

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@CawaMS and I would like to update the Aspire template to use HybridCache instead of OutputCache.

@DamianEdwards mentioned that today the template doesn't use caching at all in the API service and we still don't have client integration for HybridCache so this would require some design work to hook up correctly.

Additional context

https://learn.microsoft.com/en-us/aspnet/core/performance/caching/hybrid?view=aspnetcore-9.0

[eerhardt]

and we still don't have client integration for HybridCache

Note: I don't think there will be a client integration for HybridCache. Instead, the HybridCache would be hooked up to a distributed cache, which would come from a client integration (ex. Redis). HybridCache doesn't use a connection to an external service, which is what client integrations are for. For regular libraries (like HybridCache), you just use the library directly in an Aspire app.

So the high-level steps in are:

1. Add HybridCache "the normal way" - builder.Services.AddHybridCache();
2. Add a distributed cache via an Aspire client integration (Aspire.StackExchange.Redis.DistributedCaching)
   • The HybridCache will automatically hook up to the distributed cache
3. Use the HybridCache in your application

cc @mgravell

[mgravell]

That ties up well with my understanding, and is why I didn't leap in with integrations initially; perhaps the only thing we're missing here is an example / documentation / whatever of the same; if it has come up as a question once, it'll keep coming up

[DamianEdwards]

Can someone put in this issue what the code would have to change to in order to use Hybrid Cache?

[claudiaregio]

Can someone put in this issue what the code would have to change to in order to use Hybrid Cache?

@CawaMS already took a crack at doing it with her own private repo and we are looking for someone to validate @mgravell @eerhardt

https://github.com/[CawaMS/AspireCaching-HybridCache](https://github.com/CawaMS/AspireCaching-HybridCache)

https://github.com/CawaMS/AspireCaching-HybridCache/blob/b66c0b38babd06bb8c5be5aa58a761e1560d7af8/Aspire-HybridCache.ApiService/Program.cs#L17

https://github.com/CawaMS/AspireCaching-HybridCache/blob/b66c0b38babd06bb8c5be5aa58a761e1560d7af8/Aspire-HybridCache.ApiService/Program.cs#L48

[DamianEdwards]

The template doesn't have caching in the API service today, it's in the frontend web all instead, so that it doesn't have to call the backend service every time. Setting up Hybrid Cache looks like quite a bit more code than using Output Cache? Is there a way to make it more streamlined?

[eerhardt]

Setting up Hybrid Cache looks like quite a bit more code than using Output Cache? Is there a way to make it more streamlined?

HybridCache is more of a replacement/alternative to IDistributedCache than it is for OutputCache.

[DamianEdwards]

HybridCache is more of a replacement/alternative to IDistributedCache than it is for OutputCache.

If that's the case I'm not sure it makes sense to straight swap out the template's use of Output Cache for Hybrid Cache. The proposal seems more to add it, but I'd question whether that's worthwhile given the amount of code required and the simplistic scenario the template covers.

[CawaMS]

@DamianEdwards
Thanks for considering the suggestion to add HybridCache into the .NET Aspire starter template!

A few things I wish to clarify:

1. We wish to add HybridCache in addition to OutputCache. Not to replace.

2. HybridCache accelerates the data API performance even further than coding directly using the Redis client libraries. This is due to the combined usage of in-memory and external caching store. This brings unique, differentiated value add from .NET 9.

3. This is to advertise the idea a bit: Integrating HybridCache with Aspire would help positioning Aspire as the framework for performance critical microservice applications. Deeper caching integration aligns with the goals for resource efficiency, resiliency, and data availability in microservice world. :)

[DamianEdwards]

HybridCache accelerates the data API performance even further than coding directly using the Redis client libraries. This is due to the combined usage of in-memory and external caching store. This brings unique, differentiated value add from .NET 9.

This the part I'm not following though. The API service in the template doesn't talk to any external systems, so won't benefit from any caching at all, right? I appreciate the desire to promote Hybrid Cache, but adding it to a template in way that it doesn't actually demonstrate why it's useful or add any improvement likely isn't the best way to do it.