[syntrust]

Background

Beacon API response structure changed as ePBS introduced by the Gloas fork.

A beacon block is now decoded by its consensus version

• deneb/electra/fulu through the execution payload:

body.execution_payload.block_number
body.blob_kzg_commitments

• Gloas through the signed execution payload bid.

body.signed_execution_payload_bid.message.block_hash
body.signed_execution_payload_bid.message.blob_kzg_commitments

Both yield the execution block number/hash plus the blob commitments in block order.

What

• Blob lookup no longer needs an execution block number: PutBlob events are fetched for the execution block hash directly, so gloas blocks (whose bid carries no block number) work.
• Returned blobs follow the block's commitment order regardless of request order or event order.
• Failures are distinguishable: unknown slot, or a blob the node hasn't stored, are 404; beacon unreachable/timeout/invalid response, or a block version the archiver cannot decode, are 502; an execution block L1 has not seen yet is a retryable 503. A block that exists but cannot be decoded is never reported as "not found".
• Upstream beacon requests carry the caller's deadline and a response size cap.

Test

• Parser driven by fixtures for every supported version, including a gloas block with no execution payload and one with no blobs; missing fields, bad hash/commitment lengths, bad JSON and unknown versions are asserted to surface as upstream errors, never 404.
• End-to-end: the API runs against a fake beacon node, a fake execution client and a real shard file. Three blobs stored at shuffled kv indices, reported by the execution client in a third order, come back in commitment order and filtered to the requested hashes; the getLogs request is asserted to carry blockHash with no fromBlock/toBlock.
• Error paths covered end-to-end: blob not stored 404, execution block unknown to L1 503, beacon 404, unsupported version 502.
• go test ./... -tags ci green; go build -v ./cmd/... clean; golangci-lint run --config=./golangci.yml clean on the touched packages.
• Manual test: set up a local es-node with new blobs uploaded, request the same blob from the CL and local Archiver, then compares their raw bytes.

INFO [10-12|17:48:43.723] Blob archiver API request                from=127.0.0.1:61526 url="/eth/v1/beacon/blobs/11338222?versioned_hashes=0x015e3a80cfd2299cb42eea242685b17fb35eabfb6c7b9f0a453b14b4d689fd0e"
INFO [10-12|17:48:44.200] BeaconID to execution block              beaconID=11338222 version=gloas                       slot=11,338,222 elBlockHash=905050..e590d9 blobsInBlock=18
INFO [10-12|17:48:44.568] Parsing event                            blobHash=015e3a..89fd0e event="0 of 6"
INFO [10-12|17:48:44.568] Blobhash matched                         blobhash=015e3a..89fd0e index=0 kvIndex=0
INFO [10-12|17:48:44.604] Parsing event                            blobHash=01b2e3..799f8e event="1 of 6"
INFO [10-12|17:48:44.604] Parsing event                            blobHash=0188a5..990db9 event="2 of 6"
INFO [10-12|17:48:44.604] Parsing event                            blobHash=017085..73ca85 event="3 of 6"
INFO [10-12|17:48:44.604] Parsing event                            blobHash=01c793..80d6f5 event="4 of 6"
INFO [10-12|17:48:44.604] Parsing event                            blobHash=01216a..000aab event="5 of 6"
INFO [10-12|17:48:44.604] Query blobs done                         beaconID=11338222 blobs=1