一些背景知识。我想删除AWS红移集群，这个过程可能需要超过30分。所以，这就是我想要做的：

Some background. I want to delete AWS Redshift cluster and the process takes more than 30 minute. So this is what I want to do:

开始删除 在每1分钟，确认集群的状态（这应该是删除） 当集群被删除，该命令会失败（因为它 找不到群集了）。因此，记录一些消息，并继续执行脚本的其余部分 Start the deletion Every 1 minute, check the cluster status (it should be "deleting") When the cluster is deleted, the command would fail (because it cannot find the cluster anymore). So log some message and continue with rest of the script

这是我在，而循环来检查群集状态运行该命令后，我开始删除：

This is the command I run in a while loop to check the cluster status after I start the deletion:

resp = redshift.client.describe_clusters(:cluster_identifier=>"blahblahblah")

上面的命令会得到我的群集状态为删除而删除过程仍在继续。但是，一旦集群被完全删除，那么该命令本身会失败，因为它无法找到集群 blahblahblah 。

Above command will get me cluster status as deleting while the deletion process continues. But once the cluster is completely deleted, then the command itself will fail as it cannot find the cluster blahblahblah.

下面是命令的错误，一旦集群被删除：

Here is the error from command once the cluster is deleted:

/var/lib/gems/1.9.1/gems/aws-sdk-1.14.1/lib/aws/core/client.rb:366:in `return_or_raise': Cluster blahblahblah not found. (AWS::Redshift::Errors::ClusterNotFound)

我同意这种错误。但是，这让我的脚本退出突然。所以，我要记录一个消息，说集群被删除....继续，并继续我的脚本。

I agree with this error. But this makes my script exit abruptly. So I want to log a message saying The cluster is deleted....continuing and continue with my script.

我试过下面设置

resp = redshift.client.describe_clusters(:cluster_identifier=>"blahblahblah")
 || raise ("The cluster is deleted....continuing")

在 https://www.ruby-forum.com/提到

我也试过情侣暗示主题/ 133876 但是，这是行不通的。上述命令未能找到集群脚本我退出一次。

I also tried couple of suggestion mentioned at https://www.ruby-forum.com/topic/133876 But this is not working. My script exits once above command fails to find the cluster.

问题： 如何忽略错误，打印自己的消息说群集被删除....继续并继续脚本？

Questions: How to ignore the error, print my own message saying "The cluster is deleted....continuing" and continue with the script ?

感谢。

推荐答案

@NewAlexandria，我改变了你的code看起来像如下：

@NewAlexandria, I changed your code to look like below:

puts "Checking the cluster status"
begin
  resp = redshift.client.describe_clusters(:cluster_identifier=>"blahblahblah")
rescue AWS::Redshift::Errors::ClusterNotFound => cluster_exception
  puts "The cluster is deleted....continuing"
end
puts "seems like the cluster is deleted and does not exist"

输出：

Checking the cluster status
The cluster is deleted....continuing
seems like the cluster is deleted and does not exist

我改变了募集到看跌在紧跟在救援线在你的回应。这样，我摆脱了 RuntimeError 我提到我上面的评论。

I changed the raise to puts in the line that immediately follows the rescue line in your response. This way I got rid of the RuntimeError that I mentioned in my comment above.

我不知道这有什么寓意。我甚至不知道这是否是正确的方式来做到这一点。但它示出了当未找到的群集的误差，然后与脚本继续

I do not know what are the implication of this. I do not even know whether this is the right way to do it. But It shows the error when the cluster is not found and then continues with the script.

后来我看了很多文章，红宝石例外/救援/升/扔 ....但是那只是对我来说太多了解，因为我不属于编程背景的。所以，如果你能解释一下是怎么回事，它会非常有帮助，我得到更多的信心，红宝石。

Later I read a lot of articles on ruby exception/rescue/raise/throw.... but that was just too much for me to understand as I do not belong to programming background at all. So, if you could explain what is going on here, it will really helpful for me to get more confidence in ruby.

感谢您的时间。