public String getStreamNamespace(String systemName, String streamName) {
    LOG.info("Obtaining name-space for system: {} physical name: {}", systemName, streamName);
    return validateRequiredConfig(getFromStreamIdOrName(CONFIG_STREAM_NAMESPACE, streamName),
            "Namespace", systemName, streamName);
  }
Get the Event Hubs namespace for the stream

@param systemName name of the system
@param streamName name of stream (physical or streamId)
@return Event Hubs namespace
samza-azure/src/main/java/org/apache/samza/system/eventhub/EventHubConfig.java