Have ShardingAdapter recursively call the underlying IMessageExtractor

[Aaronontheweb]

Changes

close #7470

Checklist

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• Design discussion issue Akka.Cluster.Sharding: can't recursively unpack ShardingEnvelope contents in IMessageExtractor #7470

[Aaronontheweb]

Detailed my changes

[Aaronontheweb]

Also call the underlying message extractor's EntityMessage method on the payload of the ShardingEnvelope, just in case that also needs unwrapping. This is needed in order to make sure that messages still work properly when using tools like Akka.Cluster.Sharding.Delivery, which uses the ShardingEnvelope heavily.

[Arkatufus]

Should we do a recursive search here instead, just to make doubly sure?

something in the line of

private object UnwrapShardingEnvelope(object message)
{
  object unwrapped = message;
  while(unwrapped is IWrappedMessage)
  {
    if(unwrapped is ShardingEnvelope)
      return unwrapped;
    unwrapped = unwrapped.Message;
  }
  return message;
}

[Aaronontheweb]

No because that's introducing side-effects the user is ultimately responsible for - we only care about the ShardingEnvelope specifically

[Arkatufus]

Something to think about

[Arkatufus]

Should we do a recursive search here instead, just to make doubly sure?

something in the line of

private object UnwrapShardingEnvelope(object message)
{
  object unwrapped = message;
  while(unwrapped is IWrappedMessage)
  {
    if(unwrapped is ShardingEnvelope)
      return unwrapped;
    unwrapped = unwrapped.Message;
  }
  return message;
}

[Arkatufus]

LGTM

[Aaronontheweb]

Looks like this introduced a real test failure