chore(metrics): remove dead-code branch from route-label derivation#244
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CryptoJones merged 1 commit intoMay 19, 2026
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The Prometheus middleware derived its `route` label like this:
```js
const route = (req.route && req.route.path)
|| (req.baseUrl && req.route && req.baseUrl + req.route.path)
|| '<unknown>';
```
The middle branch is unreachable:
- If `req.route` is truthy and `req.route.path` is a non-empty string,
the first branch wins. Express always sets `req.route.path` to the
matched route pattern string, never an empty string.
- If `req.route` is undefined (404 case), both first and second
branches short-circuit on `req.route` falsy.
So the `req.baseUrl + req.route.path` branch can never fire. Plus
every route in this codebase is mounted at the top-level router with
its full `/v1/...` path inline, so there is no `req.baseUrl` to
prepend in the first place.
Drop the dead branch and tighten the comment to match what the code
actually does. No behavior change.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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Closes #243.
The middle branch of the metrics middleware's
routederivation was unreachable. Bothreq.routetruthy and falsy cases were covered by the other branches;req.baseUrldoesn't exist anyway since routes mount at the top-level router with full paths.Test plan
npm run lintcleannpm test— 687 passed (no behavior change)Proudly Made in Nebraska. Go Big Red! 🌽 https://xkcd.com/2347/