[elezar]

Summary

The gateway now merges *.toml fragments from a drop-in directory over its base config file, so operators and test harnesses can customize a package-seeded gateway.toml without editing it. Test environments use the same mechanism instead of a merge script.

Related Issue

Closes #5446

Changes

• Add load_layered in config_file.rs: load the base file and the fragments, merge them in lexical order, and validate the merged result once. Tables merge key by key; scalars and arrays replace. A fragment can omit [openshell] version; the merged result must declare it.
• Attribute a validation error to the first fragment that causes it, and keep parse errors free of file contents.
• Add --config-dir / OPENSHELL_GATEWAY_CONFIG_DIR. Without them, the gateway uses gateway.d/ next to the base file when it exists. An explicit directory must exist. --config and --config-dir compose rather than exclude each other, as in CRI-O and kubelet.
• Make config preflight load the same merged result, list the files it merged, and fail on the same errors as startup. A legacy schema version still reports its version, not an unknown-field error.
• Document the directory, order and merge rules in configuration.mdx, the RPM guide and the man page.
• Install tmachine test overrides as gateway.d/90-test-overrides.toml and remove merge-gateway-toml.py and its tests.

Not covered: the Helm ConfigMap and Secret mapping from the issue's open questions, and the config preflight usage line in the man page, which does not yet list --config-dir. The e2e additional-CA overrides still edit the base file, because e2e/rust/tests/additional_ca.rs rewrites it in place.

Release Notes

Gateway configuration can be split across a base gateway.toml and *.toml fragments in gateway.d/. Later fragments override earlier ones, and config preflight reports the merged result.

Testing

• Checks appropriate to the affected code and behavior pass: cargo clippy -p openshell-server --all-targets is clean and the openshell-server lib tests pass (2686 tests); the pre-commit lint hook passed.
• Unit tests added/updated: fragment override, ordering, array replace, error attribution, redaction, secrets, version handling, and layered preflight.
• E2E tests added/updated (if applicable): the tmachine Ansible changes were not run, only parsed as YAML.

Checklist

• Follows Conventional Commits
• Commits are signed off (DCO)

[github-actions]

🌿 Preview your docs: https://nvidia-preview-pr-5489.docs.buildwithfern.com/openshell

[github-actions]

Compatibility review (advisory)

New or updated breaking changes; see the full report for all findings.

1. cli — No explicit risk acceptance found

For openshell-gateway config preflight --path FILE containing [openshell] version = 'two', detected_version=unavailable becomes detected_version=2, even without fragments.

• Impact: Automation matching the stable category=malformed detected_version=unavailable response no longer recognizes malformed schema declarations.
• Action: Preserve existing preflight detected_version semantics on this no-break train by deriving diagnostics from the actual merged version value rather than assuming schema v2.
• PR: feat(gateway): merge drop-in config fragments over the base file #5489

Review details

• Execution: complete
• Candidate: PR #5489 (31ffaa182e4e3e9658590e33a9893ea83ee8123b)
• Baseline: 1580589082f693306abd5b63a2d9fc945b0e9caa (1580589082f693306abd5b63a2d9fc945b0e9caa)
• Reviewed: rust-sdk, python-sdk, typescript-sdk, api-behavior, cli, configuration, policy, helm, state

Advisory review; publication gates are unchanged.

Branch check run