feat(edge): gate per-minor routing on published minors and add a staging zone #175
2026-08-30
feat(edge): send unsupported R minors to CRAN instead of serving them
Falling back to the flat index for an excluded minor is the silent case: risky packages there are built under another minor and fail at load time, far from the cause. Send those clients to CRAN for sources instead, which is what the router already does for an unidentifiable distro. The whole interaction has to move, not just the index. R resolves tarball URLs against the repo it was configured with, so serving the index from CRAN and tarballs from here would hand R a binary where it expects a source tarball. A client reporting no R minor at all is not excluded: mirror scripts and image builds keep getting the flat slot. - Declare the supported window once in cdn.tf as local.rpkgs_supported_minors and set KNOWN_MINORS from it on both zones, so the router cannot drift from build-env-images' LATEST/PREV1/PREV2 unnoticed. - Split the verification script into supported and excluded minors: the former must have published indexes, the latter must have none and must redirect to CRAN under --live.
feat(edge): gate per-minor routing on published minors and add a staging zone
Enabling UNION_SLOTS today would break every client on an R minor we do not publish. contribPath() redirects on any minor the User-Agent carries, without checking that the target exists and without a fallback, and only 4.4, 4.5 and 4.6 are published: a 4.3 client would be sent to a 404 and see no packages at all. - Gate routing on KNOWN_MINORS, falling back to the flat index otherwise. - Honour EXTRA_PUBLIC_HOSTS so the same script can run on a staging zone and redirect within itself instead of into production. - Add the cran-rpkgs-test pull zone with UNION_SLOTS pre-enabled, served on the bunny default hostname so it needs no DNS record. - Add scripts/verify-r-minor-routing.sh, covering all 16 slots: index reachability, the union property against flat, Path: target resolution, coverage parity across minors, and (--live) real User-Agent routing. - Cover the fallback in the edge test suite.