AddMemoryStreams in ISiloBuilder.UseSignalR can yield duplicate key

[hendrikdevloed]

The two other cases are covered by a try...catch in case the user overrode the default, but should the AddMemoryStreams also be conditional in case a SIGNALR_ORLEANS_STREAM_PROVIDER was already registered?

I registered the same memory stream in my startup code but I got an error later on (during app.Run) about a duplicate key. I can imagine the same would happen when trying to register a persistent stream type.

https://github.com/OrleansContrib/SignalR.Orleans/blob/ad56e34e7c177b5be4ae7d3afee43f324478951f/src/SignalR.Orleans/Hosting/ISiloBuilderExtensions.cs#L36C26-L36C26

To keep using the nuget code, a workaround for my particular case is here https://pastebin.com/BetpuqXM but that's not a fundamental solution.

Should there be an if clause around the AddMemoryStreams to check for the presence of a SIGNALR_ORLEANS_STREAM_PROVIDER before registering the memory stream? Try...catch doesn't seem to be a solution because it doesn't generate an exception immediately, in contrast to the previous calls.

(On a related note, should the two try..catch use some lighter non-exception-based mechanism to check for the presence instead?)