public ConfigUpgradePack getConfigUpgradePack(String stackName, String stackVersion) {
    try {
      StackInfo stack = getStack(stackName, stackVersion);
      return stack.getConfigUpgradePack();
    } catch (AmbariException e) {
      LOG.debug("Cannot load config upgrade pack for non-existent stack {}-{}", stackName, stackVersion, e);
      return null;
    }
  }
Get all upgrade config pack if it is available for a stack.

@param stackName the stack name
@param stackVersion the stack version
@return config upgrade pack for stack or null if it is
not defined for stack
ambari-server/src/main/java/org/apache/ambari/server/api/services/AmbariMetaInfo.java