A connection's clientId, once set, is immutable.
It is possible however possible to have a late initialisation of
clientId . This can be either because the library is instanced with an
authCallback, say, and the
clientId is only known when the first
authCallback is complete; or because the library only has an opaque token string, and only learns the
clientId when it gets a response from the server that has processed the token string. In both of these cases, the "immutable" requirement is satisfied, because the
clientId gets set as part of the client's first interaction with the server.