public String getStreamSasToken(String systemName, String streamName) {
    return validateRequiredConfig(getFromStreamIdOrName(CONFIG_STREAM_SAS_TOKEN, streamName),
            "SASToken", systemName, streamName);
  }
Get the Event Hubs SAS (Shared Access Signature) token for the stream

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