`DefaultConnectionInfo.getConnectionId()` can return `null`

[gsson]

Bug Report

Versions

r2dbc-proxy 1.1.5

Current Behavior

When calling getConnectionInfo() in a ProxyExecutionListener#beforeMethod() when create() is called, a non-null DefaultConnectionInfo is returned containing a null connectionId.

This is confusing since it implements the ConnectionInfo interface and should be a @NonNullApi, and ConnectionInfo.getConnectionId() isn't marked with @Nullable.

Steps to reproduce

Input Code

public class ProxyExecutionListenerImpl implements ProxyExecutionListener {
  @Override
  public void beforeMethod(MethodExecutionInfo executionInfo) {
    var connectionInfo = executionInfo.getConnectionInfo();
    if (connectionInfo != null) {
      var connectionId = connectionInfo.getConnectionId();
      Objects.requireNonNull(connectionId);
    }
  }
}

Expected behavior/code

Either initialize the ConnectionInfo with a valid connectionId or a @Nullable annotation plus adjustments to the JavaDoc

Possible Solution

Create the connectionId earlier in ConnectionFactoryCallbackHandler#invoke()