@Override
    public ClientRequest newClientRequest(String nodeId,
                                          AbstractRequest.Builder<?> requestBuilder,
                                          long createdTimeMs,
                                          boolean expectResponse) {
        return newClientRequest(nodeId, requestBuilder, createdTimeMs, expectResponse, defaultRequestTimeoutMs, null);
    }
Add a metadata request to the list of sends if we can make one
clients/src/main/java/org/apache/kafka/clients/NetworkClient.java