grib1-to-grib2: Add option to set type=fc,strem=oper as a control for…

[dsarmany]

…ecast

Description

Contributor Declaration

By opening this pull request, I affirm the following:

• All authors agree to the Contributor License Agreement.
• The code follows the project's coding standards.
• I have performed self-review and added comments where needed.
• I have added or updated tests to verify that my changes are effective and functional.
• I have run all existing tests and confirmed they pass.

🌈🌦️📖🚧 Documentation 🚧📖🌦️🌈
https://sites.ecmwf.int/docs/dev-section/multio/pull-requests/PR-257

[Copilot]

Pull request overview

This PR adds a new CLI option to grib1-to-grib2 to mark converted forecasts as “control” by forcing number=0 and setting related ensemble metadata during re-encoding.

Changes:

• Adds a --control boolean option to the tool CLI.
• Plumbs the option into runtime configuration (control_) and applies control-forecast metadata edits during conversion.
• Introduces a validation guard to restrict --control usage to specific MARS contexts.

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[Copilot]

--control currently only affects the re-encode path. If the input message is GRIB2 and copyGrib2Messages_ is true, the message is copied verbatim and the control settings are silently ignored. Consider forcing re-encoding (or emitting an explicit error/warning) when control_ is set so the option reliably takes effect.

[dsarmany]

This is okay and by design. We can already force re-encoding by passing the option --all.

[Copilot]

misc.numberOfForecastsInEnsemble.set(51) is a hard-coded ensemble size and will overwrite any value extracted from the input/mappings. If the input already provides numberOfForecastsInEnsemble, prefer keeping it; otherwise consider making the default configurable (or deriving it from context) to avoid emitting incorrect metadata for non-51-member ensembles.

Suggested change

	misc.numberOfForecastsInEnsemble.set(51);
	if (!misc.numberOfForecastsInEnsemble.isSet()) {
	misc.numberOfForecastsInEnsemble.set(51);
	}

[dsarmany]

This is a special case when the option --control is passed, which is meant to be used only if we want to override the non-ensemble input message. This key will be inferred from the input message and passed correctly when this option is not used.

[codecov-commenter]

Codecov Report

❌ Patch coverage is 0% with 12 lines in your changes missing coverage. Please review.
✅ Project coverage is 56.28%. Comparing base (210c956) to head (08f2ff0).
⚠️ Report is 5 commits behind head on develop.

Files with missing lines	Patch %	Lines
src/multio/tools/grib1-to-grib2.cc	0.00%	12 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##           develop     #257      +/-   ##
===========================================
- Coverage    56.30%   56.28%   -0.03%     
===========================================
  Files          321      321              
  Lines        21177    21188      +11     
  Branches      1684     1688       +4     
===========================================
+ Hits         11924    11925       +1     
- Misses        9253     9263      +10     

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