docs: fix ReferenceError in open-redirect example (Url -> URL) - #2465
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bjohansebas merged 1 commit intoAug 1, 2026
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The open-redirect validation example calls `new Url(...)`, but the JavaScript global is `URL`. As written, the constructor throws ReferenceError on every request, the catch block swallows it, and the example responds 400 "Invalid url" for every URL - including valid ones - so the redirect never runs. Anyone copying the snippet gets a handler that silently rejects all redirects instead of validating them.
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krzysdz
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Jul 31, 2026
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Oops. @marco-ippolito found this in #1474 (comment), the suggestion was applied in 401c6a6 and then before merging there was a force push, which reformatted the code and accidentally reverted this change.
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Thanks @krzysdz for digging up the history, and @bjohansebas for merging. Worth recording that the credit for spotting it belongs to @marco-ippolito in #1474 — the fix was applied there and then lost to a force-push before merge. I only noticed the symptom. Glad it's back. |
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Summary
The open-redirect validation example on Production Best Practices: Security calls
new Url(req.query.url), but the JavaScript global isURL. As written the constructor throwsReferenceError: Url is not definedon every request, thecatchswallows it, and the handler responds400 "Unsupported redirect"for every URL — including valid ones — so the redirect never runs. Anyone copying the snippet gets a handler that silently rejects all redirects instead of validating them.One-line fix:
Url→URL.The same snippet appears in the translated mirrors, but per
docs/i18n.mdI've only touched the English source so Crowdin can propagate it.Verified locally:
npm run checkgreen, unit tests 52/52, and a fullastro buildsucceeds with the corrected snippet in the built page.