Ensure do_close failures don't halt pipeline shutdown

[andrewvc]

Fix the shutdown code to make sure all resources are released through #do_close even if one fails. I caught this while reviewing logstash-plugins/logstash-input-beats#537

Release notes

Fix the situation where if during pipeline shutdown a filter or output plugin failed to shut down resources may not be released.

What does this PR do?

Ensures resources are released on pipeline shutdown even when exceptions are raised in #close

Why is it important/What is the impact to the user?

Without this we may leak resources

Checklist

• My code follows the style guidelines of this project
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• I have made corresponding change to the default configuration files (and/or docker env variables)
• I have added tests that prove my fix is effective or that my feature works

Author's Checklist

• [ ]

How to test this PR locally

#!/usr/bin/env bash
set -euo pipefail

PLUGIN_DIR=/tmp/do-close-repro/logstash/filters
mkdir -p "$PLUGIN_DIR"

cat > "$PLUGIN_DIR/boom_close.rb" <<'RUBY'
require "logstash/filters/base"

class LogStash::Filters::BoomClose < LogStash::Filters::Base
  config_name "boom_close"
  def register; end
  def filter(event); end
  def close; raise "boom from do_close" end
end
RUBY

# Run from the logstash repo root
./bin/logstash \
  --path.plugins /tmp/do-close-repro \
  -e '
    input  { generator { count => 3 } }
    filter { boom_close {} }
    output { stdout { codec => dots } }
  '

What to look for in the output:

A WARN line: plugin raised exception while closing, ignoring with :plugin=>"boom_close" and the boom from do_close exception in the keys.
The pipeline exits cleanly — the stdout output still closes, process terminates without hanging.

Example WARN line + subsequent output:

[2026-04-21T16:24:06,956][INFO ][logstash.agent           ] Pipelines running {count: 1, running_pipelines: [:main], non_running_pipelines: []}
...[2026-04-21T16:24:07,119][WARN ][logstash.javapipeline    ][main] plugin raised exception while closing, ignoring {pipeline_id: "main", exception: "RuntimeError", error: "boom from do_close", stacktrace: "/private/tmp/do-close-repro/logstash/filters/boom_close.rb:7:in 'close'\n/Users/andrewvc/projects/logstash/logstash-core/lib/logstash/plugin.rb:98:in 'do_close'\norg/logstash/config/ir/compiler/AbstractFilterDelegatorExt.java:90:in 'do_close'\n/Users/andrewvc/projects/logstash/logstash-core/lib/logstash/java_pipeline.rb:617:in 'close_plugin_and_ignore'\n/Users/andrewvc/projects/logstash/logstash-core/lib/logstash/java_pipeline.rb:526:in 'block in shutdown_workers'\norg/jruby/RubyArray.java:2093:in 'each'\n/Users/andrewvc/projects/logstash/logstash-core/lib/logstash/java_pipeline.rb:526:in 'shutdown_workers'\n/Users/andrewvc/projects/logstash/logstash-core/lib/logstash/java_pipeline.rb:222:in 'run'\n/Users/andrewvc/projects/logstash/logstash-core/lib/logstash/java_pipeline.rb:159:in 'block in start'", plugin: "boom_close", thread: "#<Thread:0x7be163df /Users/andrewvc/projects/logstash/logstash-core/lib/logstash/java_pipeline.rb:149 run>"}
[2026-04-21T16:24:07,121][INFO ][logstash.javapipeline    ][main] Pipeline terminated {"pipeline.id" => "main"}
[2026-04-21T16:24:07,467][INFO ][logstash.pipelinesregistry] Removed pipeline from registry successfully {pipeline_id: :main}
[2026-04-21T16:24:07,477][INFO ][logstash.runner          ] Logstash shut down.
andrewvc@avcwork ~/p/logstash (fix-do-close-guarantees)>

[github-actions]

🤖 GitHub comments

Just comment with:

• run docs-build : Re-trigger the docs validation. (use unformatted text in the comment!)
• run exhaustive tests : Run the exhaustive tests Buildkite pipeline.

[mergify]

This pull request does not have a backport label. Could you fix it @andrewvc? 🙏
To fixup this pull request, you need to add the backport labels for the needed
branches, such as:

• backport-8./d is the label to automatically backport to the 8./d branch. /d is the digit.
• If no backport is necessary, please add the backport-skip label

[andrewvc]

Delegators prevented the previous code from working for filters / outputs. Now we prefer the instance form.

[yaauie]

👍 good find.

[mashhurs]

👍

[elasticmachine]

💚 Build Succeeded

• Buildkite Build
• Commit: c5004f7

History

• 💔 Build #4741 failed 1045adb

cc @andrewvc

[mashhurs]

LGTM!