Fix Torznab/Prowlarr download URL rewrite to avoid proxy double-wrapping on host aliases

[Copilot]

Questarr started failing all torrent downloads after the Torznab rewrite logic began re-wrapping Prowlarr download links. When Prowlarr returned its own proxy URL but the hostname differed by alias (localhost vs 127.0.0.1), Questarr produced a doubly wrapped link parameter that Prowlarr rejected.

• Torznab rewrite guard for existing Prowlarr proxy links

  • In server/torznab.ts, for Prowlarr-style indexers (/{id}/api):
    • If incoming link is already a Prowlarr proxy URL (/{id}/download with link query param), Questarr now rewrites only protocol/host to the configured indexer URL.
    • Questarr no longer rebuilds a new proxy URL in this case, preventing nested base64 encoding.
  • Existing behavior remains for true external/raw links: Questarr still constructs a Prowlarr proxy download URL.

• Regression coverage for hostname alias case

  • Added test in server/__tests__/torznab.test.ts to cover:
    • Configured indexer host: localhost
    • Returned link host: 127.0.0.1
    • Expected: rewritten host with preserved original link payload (no double-wrap).

const isProwlarrProxyUrl =
  /^\/\d+\/download\/?$/i.test(linkUrl.pathname) && linkUrl.searchParams.has("link");

if (isProwlarrProxyUrl) {
  linkUrl.protocol = indexerUrlObj.protocol;
  linkUrl.host = indexerUrlObj.host;
  torznabItem.link = linkUrl.toString();
}

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[Doezer]

/deploy tag=Prowlarr-host-rewrite

[chatgpt-codex-connector]

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[chatgpt-codex-connector]

Restrict proxy detection before skipping wrapping

When a Prowlarr-backed indexer returns a raw external download URL whose path happens to match /<digits>/download and includes a link query parameter, this new check classifies it as an existing Prowlarr proxy solely from the path/query. In that case Questarr rewrites the host to Prowlarr but skips the code that base64-wraps the original URL and adds the configured apikey, so downloads from trackers using that URL shape are sent to Prowlarr as malformed proxy requests instead of the intended raw external URL. The guard should also verify that the returned URL is actually from the configured Prowlarr host/known alias (and ideally the same indexer id) before taking this branch.

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