The direct-mount REST package door answers 500 INTERNAL_ERROR for coded 4xx errors the dispatcher twin maps correctly

[huangyiirene]

Filed by the domain:metadata PM seat on behalf of #7780's dev, which measured this while implementing PR #7995 but could not file it — the objectstack-ai org has no Claude GitHub App connection, so cloud dev containers are blocked from the GitHub API. Filed unassigned; nobody is on it.

The defect

The two doors of the package routes disagree about how a coded, status-carrying error reaches the client.

• Dispatcher twin — errorFromThrown (packages/runtime/src/http-dispatcher.ts:722-728) reads e.status first, so a protocol throw carrying .status = 400 and a ledger-declared .code surfaces as a 400 with that code.
• Direct-mount REST registrar — packages/rest/src/package-routes.ts has four catch-alls (around :295, :365, :411, :498) that do sendError(res, 500, 'INTERNAL_ERROR', …) regardless of .status / .code. They are status-blind.

So the same throw yields a 400 through one door and a 500 through the other.

⚠️ The 500 is the one production actually returns: that registrar is registered first and matches first in the production stack.

Reachability — today, not hypothetically

packageService.publish and .delete both execute inside those catch blocks, and packages/metadata-protocol already throws coded, status-carrying errors from that call path (DESTRUCTIVE_CHANGE at 409 being the established example). So a caller hitting a legitimate 409 conflict on the direct-mount door is told 500 INTERNAL_ERROR instead.

⚠️ Honest limit on the evidence, recorded by the measuring dev: "I did not do an end-to-end reproduction; the mechanism is read from the code." Whoever picks this up should reproduce before fixing, and pair any zero-hit with a control that exists now.

Why it is filed separately rather than fixed in #7995

#7995 (#7780) added TENANT_SCOPE_REQUIRED at 400 in deletePackage. Its REST door declares allTenants: true, which makes that particular refusal unreachable on that path — so #7995 neither triggers nor fixes this. It is an independent, general defect about the door's error mapping, and folding it into a tenancy PR would have widened that PR's blast radius for no reason.

Suggested shape (not a ruling)

Make the four catch-alls honour .status and .code the way errorFromThrown does — ideally by sharing that mapping rather than reimplementing it, since two copies of an error-mapping rule is how the divergence arose.

⚠️ The pin should be an AGREEMENT pin, not a presence pin: assert that both doors map the same throw to the same status and code, across throws that genuinely differ (a coded 4xx, a coded 409, and a genuinely unexpected error that should be a 500), plus an anti-vacuity case proving the doors are actually exercised. Asserting only "the REST door returns 409 for a DESTRUCTIVE_CHANGE" passes again the day someone special-cases that one code — the same defect one layer over.

Routing

⚠️ The fix lands in packages/rest, which is not domain:metadata's scope — filed without a domain: label so the triage seat can route it (domain:cli owns packages/rest, on this seat's reading). Recorded here rather than acted on.

[hotlong]

Triage: lands in packages/rest/src/package-routes.ts (the four status-blind catch-alls) → domain:cli; queued pm:queue.

The suggested shape is endorsed as the direction: share errorFromThrown's mapping rather than reimplement it — two copies of an error-mapping rule is how this divergence arose. The filer's pin guidance is adopted as acceptance: an agreement pin asserting both doors map the same throws (a coded 4xx, a coded 409, and a genuinely unexpected 500) to the same status and code, plus an anti-vacuity case — not a presence pin on any single code.

Mechanism is read from code (recorded honestly on the card); reproduce the 409→500 shape before fixing, pairing any zero-hit with a control that exists now.

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[hotlong]

Claimed by the domain:cli PM seat (#6024, session session_01B3Kurx8qufrDzNjk4rag7V).
Branch: claude/issue-8016-package-door-coded-error-mapping · dispatch: mode:subagent, model: claude-opus-5.

Anchor verified: packages/rest/src/package-routes.ts has four catch sites — :295, :365, :411, :498 — all sendError(res, 500, 'INTERNAL_ERROR', (error as Error).message). A coded 4xx thrown from below arrives at the client as a server fault, and the caller is told the platform broke when in fact they were refused.

Ruling: reuse the dispatcher's mapper — ⛔ do not hand-write a second one

The dispatcher twin already maps these correctly. That is the whole shape of the fix: one mapping, two doors. ⛔ Writing a second if (code === …) ladder here would be the sixth one-rule-two-implementations bug this lane has closed today, authored deliberately.

Find what the dispatcher path uses, reuse it, and if it is not importable from packages/rest say so with the reason — that is a finding and it changes the shape of the fix.

⚠️ Read :225 before you touch anything

That comment states the intent — "an unexpected throw is INTERNAL_ERROR. Only …". Determine whether it is correct and the code drifted from it, or whether it describes a narrower scope than the four sites now cover. Those lead to different diffs, and the comment is evidence either way. ⛔ Do not "fix" the code into disagreeing with a comment that was right; ⛔ do not leave a comment that is now false.

The 500 fallback must survive

A genuinely unexpected throw still answers 500 INTERNAL_ERROR. ⛔ Do not map everything and leave nothing on the default arm — that would trade one wrong answer for another, and it would hide real faults.

⚠️ Message leakage: 5xx bodies on this repo's HTTP boundaries run through looksLikeInternalErrorLeak before shipping (packages/types/src/error-leak.ts). Check whether this door applies it; if it does not, that is a separate finding — record it, ⛔ do not fix it here.

Pins

• Each of the four sites: a coded 4xx thrown from below arrives with its own status and its own code — assert both (ADR-0112).
• Parity with the dispatcher twin: the same thrown error answers the same status + code on both doors, asserted by comparing the two rather than by two hand-written literals. That is the pin that keeps them converged.
• The default arm still answers 500 INTERNAL_ERROR for an uncoded throw.
• Reverse-verify: revert one site, confirm its test fails by getting the 500 — the defect reproduced, not a compile error.

packages/rest TEST_DEBT is 155 with no margin. ⛔ Never raise the ledger.

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Generated by Claude Code

[hotlong]

{
 "issue": 8016,
 "status": "done",
 "branch": "claude/issue-8016-package-door-coded-error-mapping",
 "pr_url": "https://github.com/objectstack-ai/objectstack/pull/8088",
 "premise_still_valid": true,
 "mapper_reused": "Yes, but NOT by importing the dispatcher's. `errorFromThrown` is a private method of `HttpDispatcher` in `@objectstack/runtime`, and `@objectstack/runtime` DEPENDS ON `@objectstack/rest` — the import can only point one way, so it is genuinely unreachable from the REST door. Per the ruling that this is a finding which changes the fix: the rule was extracted to `resolveThrownHttpError` in `@objectstack/types` (which depends only on `@objectstack/spec`, and already hosts `sendOk`/`sendError` and `looksLikeInternalErrorLeak` for exactly this argument), and `HttpDispatcher.errorFromThrown` was rewritten to be its OTHER CALLER — now three lines. No second `if (code === …)` ladder exists. `validation-failure.ts` moved with it for reachability and is re-exported from its old runtime module path, so all 16 import sites are untouched.",
 "comment_225_verdict": "CORRECT, and the code had drifted WIDER than it. The sentence is 'an unexpected throw is INTERNAL_ERROR'; the four catch-alls treated EVERY throw as unexpected. The word doing the work is 'unexpected' — a throw declaring its own status and a registered code is a refusal, not a fault. The fix aligned the code to the comment, so the sentence is left VERBATIM (it was never what was wrong) with a `[#8016]` paragraph appended recording which of the two was drifting and where a coded refusal now exits.",
 "sites_fixed": "All four — :295 (POST /packages/publish), :365 (GET /packages), :411 (GET /packages/:id), :498 (DELETE /packages/:id). All four now call one local `sendThrownError(res, error)` which delegates to the shared resolver.",
 "default_arm_preserved": "Yes. A throw declaring neither status nor a registered code resolves to the caller's fallback 500, code derived as INTERNAL_ERROR. Pinned per site ('an uncoded throw still answers 500 INTERNAL_ERROR', 4 cases) and again in the runtime half. Reverse verification confirms it was never the defect: that case stayed GREEN on the reverted site while the coded cases went red.",
 "leak_filter_applied": "NO — confirmed and filed as #8086, not fixed here. `package-routes.ts` has zero call sites for `looksLikeInternalErrorLeak`, and the shared `sendError` (`packages/types/src/response-envelope.ts`) does not apply it either. Both siblings DO: `HttpDispatcher.error` (#3867) and `rest-server.ts` (:1355, :9019). Not a regression from this PR — the old 500 arm shipped `(error as Error).message` verbatim too — but a coded 5xx now arrives here as a 5xx with its own code, which makes the gap easier to reach deliberately. #5437 / PR #5464 fixed this class one seam over and did not reach this registrar.",
 "tests_added": "Two files, 47 + 15 cases. `packages/rest/src/package-routes-coded-error-mapping.test.ts`: each of the four sites x (coded 400 `status`, coded 409 `status`, coded 409 `statusCode`) asserting BOTH status and code (ADR-0112), plus per-site uncoded-throw-is-500 and unregistered-code cases, plus a 6-shape comparison against the shared resolver, plus anti-vacuity (200 publish, 404 get). `packages/runtime/src/package-door-error-parity.test.ts`: the dispatcher half, through the REAL `dispatcher.domainDeps.errorFromThrown` (the exact function `domains/packages.ts` calls), same shapes, plus an explicit pin on the one code difference. Every case asserts the throwing seam was actually invoked; both files assert the shapes produce >3 distinct answers so the comparison is not two constants.",
 "reverse_verification": "Direction predicted BEFORE running: coded cases red with an observed 500/INTERNAL_ERROR; the uncoded-throw case GREEN (never the defect). Reverted ONE site (POST /packages/publish) to `sendError(res, 500, 'INTERNAL_ERROR', (error as Error).message)`. Observed: `Tests 9 failed | 38 passed (47)`, ALL nine on that site, e.g. `AssertionError: expected 500 to be 409` (the established DESTRUCTIVE_CHANGE case) and `expected { status: 500, code: 'INTERNAL_ERROR' } to deeply equal { status: 409, …(1) }`. Also `expected 500 to be 400` (TENANT_SCOPE_REQUIRED) and `expected 500 to be 403` (statusCode spelling). The uncoded-throw case and the three other sites stayed green — a real defect reproduction on the live handler, not a compile error. This also discharges the card's 'reproduce before fixing' instruction: the issue was filed with the mechanism read from code, and the 409-to-500 shape is now driven.",
 "tests": "@objectstack/rest 98 files / 1613 passed. @objectstack/runtime 143 files / 2179 passed. @objectstack/types 9 files / 230 passed. `pnpm typecheck` clean on all three. check:type-check-debt does NOT rise — re-measured with the test exclusion removed: @objectstack/rest = 155 (recorded 155), @objectstack/runtime = 227 (recorded 227), zero errors attributable to either new test file. check:nul-bytes, check:route-envelope, check:error-code-casing green; ESLint clean on all changed files. Changeset added, stating the wire status-code change plainly.",
 "out_of_scope_findings": [
 "filed as #8086: the direct-mount package door ships 5xx messages verbatim — no `looksLikeInternalErrorLeak` withholding, unlike the dispatcher twin and unlike rest-server's own exits (the leak-filter finding this card asked me to record and not fix)",
 "filed as #8087: the dispatcher emits unregistered `error.code` values verbatim (`STORAGE_FAILURE`, `FLOW_FAILED`, `DUPLICATE`) — three suites pin bodies that `ApiErrorSchema` would reject"
 ],
 "risks": [
 "WIRE BEHAVIOUR CHANGE on a live surface, by design: requests to /api/v1/packages that return 500 INTERNAL_ERROR today will return the refusal they always were (409 / 400 / 403). A client keying on 500 to mean 'platform down, retry' must key on `code`. Said plainly in the changeset.",
 "The dispatcher's `errorFromThrown` was rewritten to delegate. Output is wire-identical by construction (same precedence table, `details` assembly preserved including the non-string-`code`-stays-context rule from #3842) and all 143 runtime test files pass — but this is a shared exit used by /meta, /actions, /mcp, /ui and endpoint-executor, so its blast radius is wider than the card's surface.",
 "Attempting full code parity FIRST turned four existing runtime tests red (STORAGE_FAILURE / FLOW_FAILED / DUPLICATE are unregistered and pinned as reaching the wire). Rather than rewrite those pins, the resolver returns two spellings from one function — `code` (narrowed, REST door) and `declaredCode` (verbatim, dispatcher). Doors agree on status ALWAYS and on code for every REGISTERED code; they differ only for a code the ledger does not know. Documented at the resolver, pinned explicitly, and escalated as #8087. If the PM wants full parity instead, that is #8087's decision and a one-line change here.",
 "The two-door comparison had to be SPLIT across two files: `registerPackageRoutes` is not part of `@objectstack/rest`'s public surface and `rest` cannot import `runtime`, so no single file can see both doors. Each door is pinned to the shared resolver from its own side and the halves compose; each is independently falsifiable. A literal one-file two-door assertion would have needed a new public export on `@objectstack/rest`, which is scope creep on that package's API."
 ],
 "open_questions": []
}

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Generated by Claude Code