curator_cli forcemerge exception

[Daniel314]

This issue has already been discussed on the Elastic forum: https://discuss.elastic.co/t/curator-forcemerge-exception/354245

To submit a bug or report an issue

I've discovered that the current version of curator_cli (version 8.0.10) will throw an Exception on forcemerge when the index in question is already at/below the requested number of segments per shard.

Expected Behavior

The curator_cli program should filter out indices as candidates to forcemerge when they are already at/below the requested number of segments per shard.

Actual Behavior

The curator_cli program throws an exception and exits with a nonzero exit code when the specified index already has the requested number of segments per shard.

Steps to Reproduce the Problem

## Verify that the index in question only has one sesgment per shard
$ curl -sS -XGET http://localhost:9200/cmulogstash-2024.02.21/_segments | jq '[ .. | .shards? // empty | to_entries[] | { "key":"shard \(.key)", "value":.value[0].num_committed_segments }] | flatten | from_entries'
{
  "shard 0": 1,
  "shard 1": 1
}
## Try to perform a forcemerge on the index
$ curator_cli --loglevel DEBUG  --request_timeout 14400 forcemerge --ignore_empty_list --max_num_segments 1 --filter_list '[{"filtertype":"pattern","kind":"prefix","value":"cmulogstash-2024.02.21"}]'
[ ... ]
2024-02-27 10:00:45,867 DEBUG          curator.indexlist             needs_data:266  Indices: ['cmulogstash-2024.02.21'], Fields: ['age', 'number_of_replicas', 'number_of_shards', 'routing']
2024-02-27 10:00:45,867 DEBUG          curator.indexlist          indices_exist:201  BEGIN indices_exist
2024-02-27 10:00:45,874 DEBUG          curator.indexlist             needs_data:281  These indices need data in index_info: ['cmulogstash-2024.02.21']
2024-02-27 10:00:45,875 DEBUG          curator.indexlist            data_getter:224  BEGIN data_getter
2024-02-27 10:00:45,875 DEBUG          curator.indexlist          indices_exist:201  BEGIN indices_exist
2024-02-27 10:00:45,881 DEBUG          curator.indexlist     get_index_settings:310  Getting index settings -- END
2024-02-27 10:00:45,881 DEBUG          curator.indexlist          filter_closed:802  Filtering closed indices
2024-02-27 10:00:45,881 DEBUG          curator.indexlist        get_index_state:320  Getting index state -- BEGIN
2024-02-27 10:00:45,881 DEBUG          curator.indexlist       empty_list_check:400  Checking for empty list
2024-02-27 10:00:45,882 DEBUG          curator.indexlist             needs_data:266  Indices: ['cmulogstash-2024.02.21'], Fields: ['state']
2024-02-27 10:00:45,882 DEBUG          curator.indexlist          indices_exist:201  BEGIN indices_exist
2024-02-27 10:00:45,887 DEBUG          curator.indexlist             needs_data:279  Always check open/close for all passed indices
2024-02-27 10:00:45,887 DEBUG          curator.indexlist             needs_data:281  These indices need data in index_info: ['cmulogstash-2024.02.21']
2024-02-27 10:00:45,891 DEBUG          curator.indexlist       empty_list_check:400  Checking for empty list
2024-02-27 10:00:45,892 DEBUG          curator.indexlist           working_list:411  Generating working list of indices
2024-02-27 10:00:45,892 DEBUG          curator.indexlist          filter_closed:808  Index cmulogstash-2024.02.21 state: open
2024-02-27 10:00:45,892 DEBUG          curator.indexlist           __actionable:41   Index cmulogstash-2024.02.21 is actionable and remains in the list.
2024-02-27 10:00:45,892 DEBUG          curator.indexlist     get_segment_counts:387  Getting index segment counts
2024-02-27 10:00:45,892 DEBUG          curator.indexlist       empty_list_check:400  Checking for empty list
2024-02-27 10:00:45,892 DEBUG          curator.indexlist            data_getter:224  BEGIN data_getter
2024-02-27 10:00:45,892 DEBUG          curator.indexlist          indices_exist:201  BEGIN indices_exist
2024-02-27 10:00:45,898 DEBUG          curator.indexlist           working_list:411  Generating working list of indices
2024-02-27 10:00:45,898 DEBUG          curator.indexlist       __not_actionable:44   Index cmulogstash-2024.02.21 is not actionable, removing from list.
2024-02-27 10:00:45,898 DEBUG          curator.indexlist            __excludify:63   Removed from actionable list: cmulogstash-2024.02.21 has 2 shard(s) + 1 replica(s) with a sum total of 4 segments.
2024-02-27 10:00:45,899 DEBUG          curator.indexlist       empty_list_check:400  Checking for empty list
2024-02-27 10:00:45,899 CRITICAL  curator.cli_singletons.cli_action.forcemerge    do_singleton_action:224  Failed to complete action: forcemerge.  <class 'Exception'>:

Specifications

• Version: 8.0.10
• Platform: Ubuntu 22.04 (it shouldn't matter)
• Subsystem: curator / forcemerge

Context (Environment)

I have a script that runs nightly to forcemerge cold indices down to a single segment. It depends on script exit codes to check for errors/issues with Elastic index processed. Per the discussion in the Elastic forum (see the link at the beginning of this issue), I'm putting in a feature request to ask that curator_cli not error out on indices that are already at or below the requested number of segments per shard.