private void maybePropagateMetadataError() {
        try {
            metadata.maybeThrowAnyException();
        } catch (Exception e) {
            backgroundEventHandler.add(new ErrorEvent(e));
        }
    }
Returns the responses of the sent requests. This method will try to send the unsent requests, poll for responses,
and check the disconnected nodes.

@param timeoutMs     timeout time
@param currentTimeMs current time
clients/src/main/java/org/apache/kafka/clients/consumer/internals/NetworkClientDelegate.java