elasticsearch - 如何在工作日在Kibana中运行一个cron表达式？

Question

我希望我的观察者仅从星期一到星期五运行。所以我正在尝试使用以下时间表:

"trigger": {
    "schedule" : { "cron" : "0 0 0/4 * * MON-FRI" }
  },
  "input": {
  ...

但是，我越来越

Error
Watcher: [parse_exception] could not parse [cron] schedule

当我试图保存观察者时。删除MON-FRI确实有帮助，但我需要它。

该表达式有效:

0 0 0/4 ? * MON-FRI

但我不确定我是否理解 ? is required for either the day_of_week or day_of_month

谢谢!

Answer 1

我相信这是您要寻找的:

"0 0 0/4 ? * MON-FRI"

您可以使用croneval检查您的cron表达式1:

$ /usr/share/elasticsearch/bin/x-pack/croneval "0 0 0/4 ? * MON-FRI"
Valid!
Now is [Mon, 20 Aug 2018 13:32:26]
Here are the next 10 times this cron expression will trigger:
1.      Mon, 20 Aug 2018 09:00:00
2.      Mon, 20 Aug 2018 13:00:00
3.      Mon, 20 Aug 2018 17:00:00
4.      Mon, 20 Aug 2018 21:00:00
5.      Tue, 21 Aug 2018 01:00:00
6.      Tue, 21 Aug 2018 05:00:00
7.      Tue, 21 Aug 2018 09:00:00
8.      Tue, 21 Aug 2018 13:00:00
9.      Tue, 21 Aug 2018 17:00:00
10.     Tue, 21 Aug 2018 21:00:00

对于第一个表达式，您将获得以下java异常:

java.lang.IllegalArgumentException: support for specifying both a day-of-week AND a day-of-month parameter is not implemented.

您还可以使用Crontab guru来获取人类可读的描述，例如:

At every minute past every 4th hour from 0 through 23 on every day-of-week from Monday through Friday.