Curator writes error logs to stdout instead of stderr

[IngaFeick]

To submit a bug or report an issue

Curator writes both standard and error logs to stdout.

Expected Behavior

I expect error logst to be written to stderr.

Actual Behavior

Error logs are written to stdout.

Steps to Reproduce the Problem

Try to run an action for which there is currently no matching index in the cluster. The config for my test case is here: #1311

Specifications

• Version: 5.5.4
• Platform: Linux
• Subsystem: Debian

Detailed Description

I ran into an issue (see [https://github.com//issues/1311|issue 1311] ) and this was the output on stdout:

2018-11-12 12:52:05,702 INFO Preparing Action ID: 1, "delete_indices" 
2018-11-12 12:52:05,712 INFO Trying Action ID: 1, "delete_indices": delete indices older than 30 days (based on index name) 2018-11-12 12:52:17,250 ERROR Unable to complete action "delete_indices". No actionable items in list: <class 'curator.exceptions.NoIndices'> 
2018-11-12 12:52:41,261 INFO Preparing Action ID: 1, "delete_indices" 
2018-11-12 12:52:41,271 INFO Trying Action ID: 1, "delete_indices": delete indices older than 30 days (based on index name) 2018-11-12 12:52:48,612 ERROR Unable to complete action "delete_indices". No actionable items in list: <class 'curator.exceptions.NoIndices'> 
2018-11-12 12:53:10,402 INFO Preparing Action ID: 1, "delete_indices" 
2018-11-12 12:53:10,412 INFO Trying Action ID: 1, "delete_indices": delete indices older than 30 days (based on index name) 
2018-11-12 12:53:18,500 ERROR Unable to complete action "delete_indices". No actionable items in list: <class 'curator.exceptions.NoIndices'> 
2018-11-12 12:53:42,567 INFO Preparing Action ID: 1, "delete_indices" 
2018-11-12 12:53:42,576 INFO Trying Action ID: 1, "delete_indices": delete indices older than 30 days (based on index name) 
2018-11-12 12:53:49,621 ERROR Unable to complete action "delete_indices". No actionable items in list: <class 'curator.exceptions.NoIndices'> 

There was no output on stderr. I expected the ERROR logs to be on stderr and see only the INFO logs on stdout.

[jeffbehl]

This bug is especially annoying when run in a kubernetes environment where stderr and stdout are the norm for logging.

[untergeek]

Possibly related to #1704

I finally have my k8s environment working and running an ECK-based Elastic stack, so I will check this out.

[jeffbehl]

Excellent. FWIW, #1726 is in the same vein in it also affects when running in k8s. We had the scenario where it was not connecting to the cluster. This error was reported to stdout (this issue) and exited with a 0 - all ok (#1726)