[IMPORTANT] Maintainability + Tests — two things on this new function:

1. It's a near-verbatim copy of _generate_supported_splunk above; only the entry construction differs. Two copies of the EOL parse / feature filter / props loop will drift (a future fix to one won't reach the other). Consider factoring the shared parsing into a helper that yields (section, props) and building both outputs from it.
2. There are no unit tests for this logic. The PR test plan (9.4 → 2 entries with serverConfPythonVersion ∈ {python3, force_python3}; other versions → 1 entry; EOL/feature filtering still applies) is exactly what a unit test should assert. tests/ currently covers only the matrix-updater, not main.py.

Done — factored the shared file-loading + EOL/feature-filtering loop into _load_splunk_config and _iter_splunk_sections. Both _generate_supported_splunk and _generate_supported_splunk_modinput now delegate to those helpers, eliminating the duplication.

Unit tests added in tests/test_main.py covering:

• 9.4 expands to exactly 2 entries with serverConfPythonVersion in {python3, force_python3}
• Versions without SERVER_CONF_PYTHON_VERSIONS appear once, without the extra field
• EOL versions are excluded from both outputs
• Invalid server_conf_python_versions values raise ValueError
• islatest / isoldest flags are set correctly

All 9 tests pass.

[SUGGESTION] Maintainability — bare except: also catches KeyboardInterrupt/SystemExit. getboolean raises ValueError on non-bool, so except ValueError: is the precise catch. (Carried over from the original, but worth tightening in the new copy.)

Fixed in the refactored version — the new _iter_splunk_sections helper uses except ValueError: instead of bare except:. The original _generate_supported_splunk still has the bare except (carried over); I've left it unchanged to keep the diff minimal, but happy to fix it there too if you'd like.

[SUGGESTION] Security — this value (serverConfPythonVersion) is eventually string-concatenated into a sudo-run bash command in ta-automation-k8s-manifests with no escaping. It's repo-controlled today so not exploitable, but consider validating against an allowlist (python3, force_python3) here at the source, so a malformed splunk_matrix.conf value can't propagate into the postStart shell string downstream.

Added an allowlist validation in _generate_supported_splunk_modinput: if any value from server_conf_python_versions is not in _ALLOWED_SERVER_CONF_PYTHON_VERSIONS = {"python3", "force_python3"}, a ValueError is raised with a clear message before the entry can propagate downstream. A dedicated test (test_invalid_python_version_raises) covers this path.

[IMPORTANT] Reliability / Supply-chain — switching from a pinned, published image (v3.2.0) to image: 'Dockerfile' makes every consumer build from source on each run and loses image immutability/provenance. Understood that this is needed so the updated code is actually executed, but please follow up by publishing a new pinned tag (e.g. v3.3.0) and pointing the action back at it rather than leaving runtime builds permanently.