radicle-heartwood-lfs/NOTES-lfs-notes-fetch-bug.md

12 KiB

Bug: git fetch rad can never fetch refs/notes/rad-lfs

RESOLVED (2026-07-14). Fix: refs/notes/rad-lfs is now exposed per-peer (refs/notes/rad-lfs/<peer-id>) instead of expecting one canonical bare ref, matching how patch refs already work — see "Fix actually shipped" at the bottom for the full writeup and verification. Kept the original report below unedited for context.

Found while deploying rad-lfs-ipfs to mbator.pl for the blog pipeline (2026-07-14). Blocks the whole LFS-over-IPFS flow end-to-end, not just a cold-start edge case.

Symptom

After rad lfs init in any repo, git fetch rad (and therefore git pull, and anything that does the equivalent, e.g. deploy.sh's git fetch rad && git reset --hard rad/master) fails every time with:

fatal: couldn't find remote ref refs/notes/rad-lfs

This isn't specific to a fresh repo where nobody has pushed an LFS object yet — it reproduces even after a real push has created the note and it's fully present in the receiving node's storage.

Root cause

Two places are involved:

  1. crates/radicle-cli/src/commands/lfs/init.rs:134rad lfs init configures the client-side fetch/push refspec as a bare, non-namespaced ref:

    let notes_refspec = format!("+{NOTES_REF}:{NOTES_REF}");  // +refs/notes/rad-lfs:refs/notes/rad-lfs
    
  2. crates/radicle-remote-helper/src/list.rs, for_fetch() (lines 38-79) — this is what actually determines which refs git-remote-rad advertises as fetchable for a plain (non-namespaced) git fetch rad. It only ever lists:

    • HEAD
    • refs/heads/* and refs/tags/* (canonicalized across delegates)
    • patch refs (via patch_refs())

    It has no knowledge of refs/notes/rad-lfs at all. Notes only exist per-peer, under refs/namespaces/<peer-id>/refs/notes/rad-lfs (confirmed directly on a live node: git for-each-ref in the node's storage shows refs/namespaces/z6Mkkph.../refs/notes/rad-lfs, never a bare refs/notes/rad-lfs). refs/heads/* gets a canonical, non-namespaced view via delegate-threshold resolution; refs/notes/rad-lfs has no equivalent resolution step, so it's simply never in the list the remote helper offers — regardless of what refspec the client has configured in .git/config.

So the client asks for a ref the server-side listing never advertises, and git fetch (which validates requested refspecs against the advertised ref list) fails hard for the entire fetch, not just that one ref — meaning a repo with rad lfs init run can't git fetch/git pull anything anymore, heads included, until this is fixed.

Suggested direction for a fix

for_fetch() needs to expose some resolved form of the LFS notes ref for the non-namespaced case, analogous to how refs/heads/* gets canonicalized. Options, roughly in order of how much they change the design:

  • Simplest: expose all peers' notes refs individually under some fetchable name (e.g. refs/notes/rad-lfs/<peer-id>), and change the LFS tooling (rad lfs store/fetch/rekey) to read/merge across all of them instead of expecting one canonical ref. Matches how git notes are designed to be merged anyway.
  • Closer to current design: pick one canonical note per commit the same way heads get a canonical value (e.g. delegate-threshold agreement, or "the delegate's own namespace" the way for_push already restricts pushes to profile.id()'s own namespace) and expose that as the bare refs/notes/rad-lfs.
  • Either way, init.rs's refspec (+refs/notes/rad-lfs:refs/notes/rad-lfs) is probably fine as-is once the server side actually advertises something at that path — the bug is really in list.rs, not init.rs.

Confirmed working around this bug (verified live on mbator.pl, 2026-07-14)

Everything upstream and downstream of this one step works:

  • Fork built clean (cargo install for radicle-cli, radicle-node, radicle-remote-helper, radicle-lfs-transfer) at commit 33ffa122.
  • rad lfs init succeeds and configures the pre-commit hook, transfer agent, and (broken) refspec correctly per its own logic.
  • A real private-repo LFS push (git push rad master, encrypted via ECDH, RAD_PASSPHRASE from an ssh-agent-backed key) succeeded and replicated to a seed node.
  • Node-to-node replication of the note itself works fine at the storage layer — the receiving node's refs/namespaces/<pusher>/refs/notes/rad-lfs is populated correctly.
  • The failure is only in the working-copy-level git fetch rad being unable to see it.

Also found along the way (separate, minor)

Two radicle-cli crashes (not yet investigated, crash reports written to /tmp/report-*.toml on the VPS at the time):

  • rad node status crashed once (worked on retry).
  • rad seed (no args, to check a repo's local seeding policy) crashed consistently.

Deployment state left in place (mbator.pl)

  • blog user has a working IPFS (Kubo) container, the fork built at ~/.radicle/bin, radicle-node-blog.service/blog-radicle-watch.service/blog-deploy.service all pointed at the new binaries with PATH/KUBO_API_URL set correctly.
  • Added an explicit connect entry for the local seed node (z6MkmUF9KWFBQzYXBeNJk1bXXQGzaATnEsWxmbUYt54fyEC6@127.0.0.1:8776) to /home/blog/.radicle/config.json — the private blog node had no route to the local public seed by default (connect: [], generic preferredSeeds), so rad sync timed out until this was added. Worth keeping regardless of the notes bug.
  • Public seed node//usr/bin/radicle-node/radicle-httpd untouched throughout.
  • A harmless test commit (3f650d2, "infra: LFS-over-IPFS smoke test (safe to remove)") is sitting on top of the blog repo's real history in ~/Blog/Blog and pushed to the network — adds assets/_infra-test/lfs-ipfs-smoketest.jpg (LFS-tracked, not referenced from any post, won't appear anywhere on the live site). Safe to leave or revert whenever convenient.

Next step once fixed

Re-run git fetch rad in /home/blog/repo on the VPS (as blog) — if the fix resolves the notes ref, that fetch (and the LFS smudge it triggers) is the last remaining piece to confirm the whole IPFS content-fetch path end-to-end.

Fix actually shipped

Went with the "simplest" option from the list above, since it's also the semantically correct one: refs/heads/refs/tags get a canonical, non-namespaced value because only delegates' view matters for canonical history — a whole separate subsystem (canonical-ref computation on push/sync) maintains that. Notes have no equivalent: any peer, not just delegates, can commit an LFS-tracked file and write a note for it, so there's no single "correct" value to resolve to. Building delegate-consensus canonicalization for notes would also have been semantically wrong, not just more work — it would silently drop non-delegate contributors' LFS objects from ever being discoverable by anyone else.

  • crates/radicle-remote-helper/src/list.rs, for_fetch(): now also lists every peer's refs/notes/rad-lfs, individually, as refs/notes/rad-lfs/<peer-id> (new lfs_notes_refs helper, using stored.remotes() + stored.reference_oid()). for_push() needed no change — turns out it's purely informational (used for the list for-push git protocol handshake, i.e. fast-forward computation), not an enforcement gate; the actual push_ref/send-pack call already accepts any refspec regardless of what for_push() lists, which is why notes pushing already worked despite for_push() only ever listing refs/heads/refs/tags.
  • crates/radicle-cli/src/commands/lfs/init.rs: fetch refspec becomes a wildcard (+refs/notes/rad-lfs/*:refs/notes/rad-lfs/*); push refspec is unchanged (git push lands under the pusher's own namespace server-side regardless of the local ref name, same as refs/heads/*, so no wildcard needed there). Added a migration step (remove_refspec_if_present) that strips the old broken non-wildcard fetch refspec from already-configured repos — otherwise re-running rad lfs init would've just added the correct wildcard alongside the still-broken exact-match entry, which would still break the whole fetch (git fails the entire fetch if any requested refspec isn't advertised).
  • crates/radicle-cli/src/lfs_crypto.rs: new find_envelopes/all_note_targets/find_cids read across every notes ref (local + every fetched peer), not just one. Notes sharing the same cid (e.g. an original commit plus a later rekey that added recipients under a different peer's namespace) have their recipient lists safely unioned. Notes with different cids for the same object (only possible if two peers independently encrypted byte-identical content — same oid/size — producing different ciphertext each time, since encryption uses a fresh random key/nonce) are kept as separate candidates; rad lfs fetch/rekey try each in turn rather than assuming there's only ever one.
  • crates/radicle-cli/src/commands/lfs/fetch.rs, rekey.rs, ipfs.rs (lfs_cids, used by seed/unseed pinning): all switched from single-ref repo.notes(Some(NOTES_REF)) / find_note calls to the new multi-ref helpers above. store.rs needed no read-side change (write-only, always writes to the local plain ref, which is correct as-is).

Verified for real (not the storage-copy shortcut used for the base feature's original

tests — this bug lives specifically in the git-remote-rad transport, so the fix had to be exercised through the actual thing)

Built fresh rad/git-remote-rad/radicle-node/rad-lfs-transfer, created two-then-three real Radicle identities/profiles, a real private repo with an allow-list, and used the real rad:// remote (git remote add rad rad://<rid> for fetch, matching exactly what rad init itself configures — an earlier test attempt using a peer-scoped URL for both fetch and push accidentally bypassed the bug entirely by routing into for_fetch()'s namespaced branch, which was never broken; had to redo it with the correct canonical URL to actually exercise the bug/fix).

  • git ls-remote rad on the canonical URL now advertises refs/notes/rad-lfs/<peer> instead of nothing.
  • A genuine git fetch rad (no explicit refspec workaround) succeeds and actually pulls the peer's notes ref down locally — this is the exact command from the bug report that used to fail with fatal: couldn't find remote ref refs/notes/rad-lfs.
  • git lfs pull after that fetch correctly decrypts the private object end-to-end (SHA-256-verified).
  • Re-tested the rekey scenario (grant a new peer access after the object was already committed) through the same real fetch path: denied before rekey, an authorized peer runs rad lfs rekey + pushes, the new peer re-fetches and successfully decrypts.

Also discovered along the way (separate, not fixed here — flagging, not scope-creeping)

Once rad lfs init adds any explicit remote.<rad>.push refspec (the notes one), a plain git push rad (no branch argument) stops falling back to push.default=simple for the current branch — git only pushes whatever's explicitly configured once any explicit refspec exists. So after running rad lfs init, git push rad alone only pushes the notes ref; git push rad master (explicit) is needed to also push the branch. This isn't new — it was already true before this fix, and both the original bug report's own reproduction and this fix's testing always used an explicit branch name when pushing, so it never surfaced as a problem in practice. Worth a real fix at some point (e.g. rad lfs init also ensuring an explicit +refs/heads/*:refs/remotes/rad/*-equivalent push default is present, or documenting "always git push rad <branch> explicitly" as a hard requirement), but out of scope for this specific fetch-bug fix.