SignalR Java client only supports exactly 1.3

Question

Is there a reason why the Java client for SignalR only supports exactly version 1.3?

https://github.com/SignalR/java-client/blob/f226631da562cfaacbe8b16d5a9ecbf8205e7c99/signalr-client-sdk/src/microsoft/aspnet/signalr/client/Connection.java#L597

Shouldn't all clients be backwards compatible? Is there any harm done and changing the verifyProtocolVersion method to verify that the protocol is less than or equal to 1.3? For testing purposes, I simply returned true, skipping the entire method body, to see if it worked with my 1.2.1 server, and it did.

Maybe this should be considered a bug?

Answer 1

SignalR protocol versions do not align with SignalR package versions. For example, the SignalR 2.0.* server supports communicating with clients using either version 1.2 or 1.3 of the SignalR protocol:

https://github.com/SignalR/SignalR/blob/2.0.3/src/Microsoft.AspNet.SignalR.Core/Infrastructure/ProtocolResolver.cs

It looks like the Java client supports the latest SignalR protocol version as of SignalR 2.0.3.