B2 application key (the secret). Masked via core.setSecret by the dispatcher.
B2 application key ID. Masked via core.setSecret by the dispatcher (defense in depth).
Target bucket name (stored on the result for later getBucket resolution).
OptionalendpointOverride the default B2 realm endpoint. Only set for staging / custom realms.
OptionaltransportInject a custom transport (used by tests with the SDK's B2Simulator).
Inputs to buildClient.