Codec's #register method is invoked a second time with the actual params and not the original cloned

[andsel]

Logstash information:

Please include the following information:

1. Logstash version (e.g. bin/logstash --version)
2. Logstash installation source (e.g. built from source, with a package manager: DEB/RPM, expanded from tar or zip archive, docker)
3. How is Logstash being run (e.g. as a service/service manager: systemd, upstart, etc. Via command line, docker/kubernetes)

Plugins installed: (bin/logstash-plugin list --verbose)

JVM (e.g. java -version):

If the affected version of Logstash is 7.9 (or earlier), or if it is NOT using the bundled JDK or using the 'no-jdk' version in 7.10 (or higher), please provide the following information:

1. JVM version (java -version)
2. JVM installation source (e.g. from the Operating System's package manager, from source, etc).
3. Value of the LS_JAVA_HOME environment variable if set.

OS version (uname -a if on a Unix-like system):

Description of the problem including expected versus actual behavior:
The register method of codecs happens during pipeline startup. That method should be invoked with the original param that the user configured in the pipeline. The register method is invoked twice:

• the first time to instantiate the codec.
• the second due to the a cloning request during the input instantiation.
  While the first time it receives the expected original_params with the params explicitly configured by the user in the pipeline config, the second one receives all the parameters.

First time call stack sample:

vendor/bundle/jruby/3.1.0/gems/logstash-mixin-ecs_compatibility_support-1.3.0-java/lib/logstash/plugin_mixins/ecs_compatibility_support/target_check.rb:48:in `register'
logstash-core/lib/logstash/codecs/base.rb:33:in `initialize'

<here enters in AbstractPipelineExt.initialize (Java class)>

logstash-core/lib/logstash/java_pipeline.rb:48:in `initialize'
logstash-core/lib/logstash/java_pipeline.rb:48:in `initialize'
logstash-core/lib/logstash/pipeline_action/create.rb:49:in `new'
logstash-core/lib/logstash/pipeline_action/create.rb:49:in `execute'
logstash-core/lib/logstash/agent.rb:386:in `block in converge_state'

Second time call stack:

vendor/bundle/jruby/3.1.0/gems/logstash-mixin-ecs_compatibility_support-1.3.0-java/lib/logstash/plugin_mixins/ecs_compatibility_support/target_check.rb:48:in `register'
logstash-core/lib/logstash/codecs/base.rb:33:in `initialize'
logstash-core/lib/logstash/codecs/base.rb:94:in `initialize_plugin'
logstash-core/lib/logstash/codecs/base.rb:94:in `clone'
logstash-core/lib/logstash/util.rb:224:in `deep_clone'
logstash-core/lib/logstash/util.rb:218:in `block in deep_clone'
logstash-core/lib/logstash/util.rb:218:in `inject'
logstash-core/lib/logstash/util.rb:218:in `deep_clone'
logstash-core/lib/logstash/plugin.rb:77:in `initialize'
logstash-core/lib/logstash/inputs/base.rb:72:in `initialize'
vendor/bundle/jruby/3.1.0/gems/logstash-mixin-ecs_compatibility_support-1.3.0-java/lib/logstash/plugin_mixins/ecs_compatibility_support/selector.rb:61:in `block in initialize'
vendor/bundle/jruby/3.1.0/gems/logstash-input-stdin-3.4.0/lib/logstash/inputs/stdin.rb:28:in `initialize'

<here enters in AbstractPipelineExt.initialize (Java class)>

logstash-core/lib/logstash/java_pipeline.rb:48:in `initialize'
logstash-core/lib/logstash/java_pipeline.rb:48:in `initialize'

Steps to reproduce:

Please include a minimal but complete recreation of the problem,
including (e.g.) pipeline definition(s), settings, locale, etc. The easier
you make for us to reproduce it, the more likely that somebody will take the
time to look at it.

1. edit a plugin's register to output the parameters, like

def register
    puts "DBG>> original_params: #{original_params}"
end

2. then configure the path to the development plugin in your Gemfile

gem "logstash-codec-json_lines", :path => "/path/to/logstash_plugins/logstash-codec-json_lines"

bin/logstash-plugin install --no-verify

3. Start Logstash with a pipeline that contains that codec in an input

Additional notes

Very likely the problem is in cloning of codec

logstash/logstash-core/lib/logstash/codecs/base.rb

Line 94 in b88e237

LogStash::Plugins::Contextualizer.initialize_plugin(execution_context, self.class, params).tap do |klone|

where it passes down params instead of original_params.
This come up also in logstash-plugins/logstash-codec-json_lines#46 (comment)

Provide logs (if relevant):

[2024-09-05T16:18:19,861][INFO ][org.reflections.Reflections] Reflections took 42 ms to scan 1 urls, producing 139 keys and 484 values

DNADBG>> original_params: {"id"=>"29dc41a3-3a5f-40d9-965f-37d0f097ee81"}

[2024-09-05T16:18:19,896][INFO ][logstash.codecs.jsonlines] ECS compatibility is enabled but `target` option was not specified. This may cause fields to be set at the top-level of the event where they are likely to clash with the Elastic Common Schema. It is recommended to set the `target` option to avoid potential schema conflicts (if your data is ECS compliant or non-conflicting, feel free to ignore this message)

DNADBG>> original_params: {"id"=>"29dc41a3-3a5f-40d9-965f-37d0f097ee81", "enable_metric"=>true, "charset"=>"UTF-8", "delimiter"=>"\n", "decode_size_limit_bytes"=>536870912}

[2024-09-05T16:18:19,906][INFO ][logstash.codecs.jsonlines] ECS compatibility is enabled but `target` option was not specified. This may cause fields to be set at the top-level of the event where they are likely to clash with the Elastic Common Schema. It is recommended to set the `target` option to avoid potential schema conflicts (if your data is ECS compliant or non-conflicting, feel free to ignore this message)
[2024-09-05T16:18:19,946][INFO ][logstash.javapipeline    ] Pipeline `main` is configured with `pipeline.ecs_compatibility: v8` setting. All plugins in this pipeline will default to `ecs_compatibility => v8` unless explicitly configured otherwise.
[2024-09-05T16:18:19,956][INFO ][logstash.javapipeline    ][main] Starting pipeline {:pipeline_id=>"main", "pipeline.workers"=>12, "pipeline.batch.size"=>125, "pipeline.batch.delay"=>50, "pipeline.max_inflight"=>1500, "pipeline.sources"=>["/Users/andrea/workspace/logstash_plugins/logstash-codec-json_lines/test_oom_pipeline.conf"], :thread=>"#<Thread:0x32d128ba /Users/andrea/workspace/logstash_andsel/logstash-core/lib/logstash/java_pipeline.rb:134 run>"}
[2024-09-05T16:18:20,168][INFO ][logstash.javapipeline    ][main] Pipeline Java execution initialization time {"seconds"=>0.21}
[2024-09-05T16:18:20,177][INFO ][logstash.javapipeline    ][main] Pipeline started {"pipeline.id"=>"main"}
The stdin plugin is now waiting for input:
[2024-09-05T16:18:20,184][INFO ][logstash.agent           ] Pipelines running {:count=>1, :running_pipelines=>[:main], :non_running_pipelines=>[]}