Hard-fail on provider CID mismatch instead of warn#110
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`create_drive` previously logged a `tracing::warn!` and continued when the provider's returned data_root disagreed with the locally-computed CID, defeating content-addressing's only integrity guarantee. Now returns a new `FsClientError::CidMismatch` and refuses to cache or proceed. Adds unit coverage for both the matching and mismatching path via a small `verify_cid` helper.
bkontur
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Jun 2, 2026
| /// Compare a locally-computed CID against the CID a provider returned for | ||
| /// the same bytes. Returns `CidMismatch` on disagreement so callers can | ||
| /// refuse to trust the provider's response. | ||
| fn verify_cid(expected: Cid, got: Cid) -> Result<()> { |
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@ilchu for this kind of check, we are using ensure_** if you check PolkadotSDK, so I would vote for ensure_cid_matches or better name :)
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| fn verify_cid(expected: Cid, got: Cid) -> Result<()> { | |
| fn ensure_cid_matches(expected: Cid, got: Cid) -> Result<()> { |
bkontur
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Jun 2, 2026
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@ilchu please check just: https://github.com/paritytech/web3-storage/pull/110/files#r3341175555
Match FRAME's `ensure!`-style naming convention for predicate helpers that return `Err` on a failed invariant rather than performing verification with side effects. No behavioural change.
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The
create_drivefunction previously logged atracing::warn!and continued when the provider's returned data_root disagreed with the locally-computed CID, defeating content-addressing's only integrity guarantee.Now returns a new
FsClientError::CidMismatchand refuses to cache or proceed. Adds unit coverage for both the matching and mismatching path via a smallverify_cidhelper.