fix(gc): keep tag manifests' digest aliases, reap manifest meta sidecars - #950
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ertime037 merged 1 commit intoSep 3, 2026
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The tag-rooted mark walk (getnora-io#938) marked a tag manifest's children (arch manifests, config, layer blobs) but not the digest-named file of the tag manifest itself. The sweep then deleted manifests/sha256:<digest>.json while manifests/<tag>.json — the same bytes — survived, so pull-by-digest 404'd while pull-by-tag worked. The walk now hashes each tag manifest's bytes and marks the sha256:<digest>.json alias as a root, per the OCI distribution spec requirement that content pullable by tag stays pullable by digest. Also reap the .meta.json sidecar together with an orphaned digest manifest; it was invisible to detection on its own and leaked forever. Fixes getnora-io#949 Signed-off-by: Joe Grund <grundjoseph@gmail.com>
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What
manifests/sha256:<digest>.json— the digest alias of the tag manifest itself — as a root, alongside the children it already marked..meta.jsonsidecar with it; the sidecar was invisible to detection on its own and leaked forever.Why
Fixes #949. Since #938 (v1.2.2), the sweep deleted
manifests/sha256:<digest>.jsonwhilemanifests/<tag>.json— the same bytes — survived, so every pull-by-digest of a tagged image 404'd after the first GC run while pull-by-tag kept working. For proxy-cached or seeded repos whose upstream has moved on, the deleted digest alias was unrecoverable. The OCI distribution spec requires content pullable by tag to stay pullable by digest.Checklist
cargo test)cargo clippy -- -D warnings)