Unable to discern address in use error

[maciejhirsz]

When the JSON-RPC address is in use, Substrate retries with a random port. This work fine with jsonrpc, but we unfortunately erase std::io errors type with anyhow.

We should have a new error variant(s) just for AddressInUse | PermissionDenied. Bonus points if we can either not consume the builder, or return the builder in the error for easy retries. Alternatively support the strategy of trying random port directly into jsonrpsee.

[niklasad1]

right, didn't think about this....

[dvdplm]

Alternatively support the strategy of trying random port directly into jsonrpsee.

I think this is highly application specific and that we should not do it in jsonrpsee.

[maciejhirsz]

Solved by #567.