chain: log duplicate-AttestationData STF rejects with full context#850
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When a block is rejected for containing duplicate AttestationData
entries, log every distinguishing field of the duplicate so the
reproduction has enough on-the-wire context to diagnose without
pulling block bytes from a peer.
Two `AttestationData` values are equal iff every field (slot, head,
target, source) matches, so the new log line includes:
- blockroot, slot, proposer_index of the offending block
- the two indices [i, j] inside the block whose data hashed to
the same value
- data.slot
- data.head.blockroot @ slot
- data.target.checkpoint_root @ slot
- data.source.checkpoint_root @ slot
The format string is intentionally split across 5 logical chunks
(block-level / data / head / target / source) so it stays diff
friendly and operators can grep individual fields. Naming
(`blockroot=` / `checkpoint_root=`) mirrors neighbouring logs in
chain.zig (e.g. line ~1867's gossip-block log).
Splits the chain.zig portion of #848 review #6 into its own PR so
the wedge-fix for #837 stays focused on node.zig + metrics.
Refs #837, #848.
Signed-off-by: zclawz <zclawz@users.noreply.github.com>
anshalshukla
approved these changes
May 12, 2026
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Splits the chain.zig portion of #848 review #6 into its own PR so the wedge-fix for #837 stays focused on
pkgs/node/src/node.zig+pkgs/metrics/src/lib.zig.What this changes
When a block is rejected for containing duplicate
AttestationDataentries, log every distinguishing field of the duplicate so the reproduction has enough on-the-wire context to diagnose without pulling block bytes from a peer.Two
AttestationDatavalues are equal iff every field (slot,head,target,source) matches, so the new log line includes:blockroot,slot,proposer_indexof the offending block[i, j]inside the block whose data hashed to the same valuedata.slotdata.head.blockroot @ slotdata.target.checkpoint_root @ slotdata.source.checkpoint_root @ slotPre-fix log:
Post-fix log:
Review nits applied (point #9 from #848)
root=normalised toblockroot=/checkpoint_root=to match neighbouring logs inchain.zig(e.g. line ~1867 gossip block log).block.proposer_indexisValidatorIndex=u64, so{d}is correct.Refs
error.DuplicateAttestationDatareject of block accepted by every other client family #837 ask update codebase to support 0.14.0 #5