Add get origin client function

[fewensa]

In this way, a healthy original client can be obtained, Only use Any to return, because there is no relay-client-substrate package dependent on this library.
This is not necessarily a good method, but it is indeed a solution.

After do that, If we create a customized relay strategy. we can get an original client from relay_reference

let client: &relay_client_substrate::Client<RialtoChain> = relay_reference.lane_source_client.origin_client().downcast_ref().unwrap();

In doing so, the biggest advantage is that third-party applications can get a client that will not lose the connection, because this has been processed in the message-lane-loop .

[svyatonik]

In doing so, the biggest advantage is that third-party applications can get a client that will not lose the connection, because this has been processed in the message-lane-loop .

Is it the only advantage? I assume that you're creating strategy using initial clients and then if disconnect occurs, loop is able to recover and your strategy isn't, right? Then imo the simplest way is to impl TargetClient/SourceClient for some struct like that (could probably be rewritten without Mutexes, but the idea is in common shared data of the cloneable client):

struct SharedSourceClient {
  shared_data: Arc<Mutex<SharedSourceClientData>>,
}

struct SharedSourceClientData {
  substrate_client: relay_substrate_client::Client<YourChain>,
}

impl RelayClient for SharedSourceClient {
  fn reconnect() {
    self.shared_data.lock().await.client.reconnect();
  }
}

Then you may simply return errors from your strategy and loop will do a reconnect.

If you have other usages for this origin_client, please comment. Thanks!

[fewensa]

Yes, The purpose of adding this method is to get the client. I will try the method your suggestion.