feat(hack): add flag extraction script for Karmada components

[sarthakkjha]

What type of PR is this?

/kind feature

What this PR does / why we need it:

This PR adds hack/extract-flags.sh, a shell script that extracts command-line flags
from Karmada component binaries and outputs structured JSON.

Karmada components accept flags from multiple sources, including Karmada code,
Kubernetes dependencies, and controller-runtime. During dependency upgrades,
flags can be silently added, removed, or modified, potentially breaking user
configurations.

This script provides an initial foundation for:

• Automated flag documentation
• CI-based flag change detection across versions
• Flag inventory tracking for Karmada releases

Which issue(s) this PR fixes:

Part of the LFX mentorship project:
"Create comprehensive documentation and tooling to track and document all flags
for Karmada's maintained components"

Special notes for your reviewer:

• Script uses only standard shell utilities (bash, grep, sed, date)
• Works on both Linux and macOS
• Handles missing binaries gracefully with clear error messages
• JSON output validated using python -m json.tool

Test run (macOS):

make all
./hack/extract-flags.sh --binary-dir=_output/bin/darwin/arm64 --output=flags.json

Output:

karmada-controller-manager: 74 flags
karmada-scheduler: 51 flags
Output written to: flags.json

Does this PR introduce a user-facing change?:

NONE

[karmada-bot]

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Details

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[karmada-bot]

Welcome @sarthakkjha! It looks like this is your first PR to karmada-io/karmada 🎉

[gemini-code-assist]

Summary of Changes

Hello @sarthakkjha, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request delivers a new shell script designed to improve the maintainability and reliability of Karmada components by systematically extracting and documenting their command-line flags. It addresses the challenge of managing flag evolution across various dependencies, providing a robust mechanism for tracking and verifying component configurations.

Highlights

• New Script for Flag Extraction: Introduces hack/extract-flags.sh, a new shell script designed to automatically extract command-line flags from Karmada component binaries and output them in a structured JSON format.
• Enhanced Configuration Stability: This tool helps prevent silent flag changes during dependency upgrades from breaking user configurations by enabling automated detection and tracking of flag evolution.
• Foundation for Tooling: Lays the groundwork for automated flag documentation, CI-based flag change detection across versions, and comprehensive flag inventory tracking for Karmada releases, fulfilling part of an LFX mentorship project.

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[gemini-code-assist]

Code Review

This pull request introduces a useful script, hack/extract-flags.sh, for extracting command-line flags from Karmada components. The script is well-structured and serves as a good foundation for automated flag documentation and change detection.

I've provided a few suggestions to improve the script's robustness and efficiency:

• Fixing a bug related to set -o pipefail that could cause the script to fail for components with no flags.
• Refactoring the command-line argument parsing to use a more standard while loop.
• Optimizing the flag extraction process to avoid redundant binary executions.

Overall, this is a valuable addition to the project's tooling.

[codecov-commenter]

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Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 46.54%. Comparing base (6592b4a) to head (f99c796).
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Additional details and impacted files

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##           master    #7136      +/-   ##
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Flag	Coverage Δ
unittests	46.54% <ø> (-0.01%)	⬇️

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[sarthakkjha]

Hi @XiShanYongYe-Chang @RainbowMango, I have added a shell script to extract command line flags from Karmada components and track changes over time. Can you please review this and let me know if we are moving in the right direction?

[RainbowMango]

@sarthakkjha Thanks for doing this. I guess this task is part of the CNCF LFX program Protect Karmada Component Flags from Unexpected Changes. Are you going to run for it?

[sarthakkjha]

@sarthakkjha Thanks for doing this. I guess this task is part of the CNCF LFX program Protect Karmada Component Flags from Unexpected Changes. Are you going to run for it?

Yes i'm planning to contribute to Karmada and I believe LFX would be a great way to start with the mentorship.

[RainbowMango]

Thank you for your enthusiasm. I appreciate your interest in contributing.

But, given that this is part of the upcoming LFX program that we've recently published, and we haven't yet started the candidate selection. To ensure fairness, I'd like to hold off on merging any implementation until the selected mentee is onboarded and begins their work under the program.

You are welcome to talk to us about your idea regarding the implementation, through channels like a community meeting.

[XiShanYongYe-Chang]

Thank you for your enthusiasm. I appreciate your interest in contributing.

But, given that this is part of the upcoming LFX program that we've recently published, and we haven't yet started the candidate selection. To ensure fairness, I'd like to hold off on merging any implementation until the selected mentee is onboarded and begins their work under the program.

You are welcome to talk to us about your idea regarding the implementation, through channels like a community meeting.

+1

[sarthakkjha]

Thank you for your enthusiasm. I appreciate your interest in contributing.

But, given that this is part of the upcoming LFX program that we've recently published, and we haven't yet started the candidate selection. To ensure fairness, I'd like to hold off on merging any implementation until the selected mentee is onboarded and begins their work under the program.

You are welcome to talk to us about your idea regarding the implementation, through channels like a community meeting.

Yes, that makes sense. My intention was mainly to get feedback on whether my thinking and overall direction were correct. We can hold off on merging for now and instead align on the right approach and foundation for implementing this as part of the LFX project.