HTTP rewards verifier

[michaelsproul]

Description

It would be great to have a tool to cross-check the rewards returned by the HTTP rewards API against balance diffs on real networks.

This would help catch bugs like:

• Fix phase0 block reward in rewards API #5101

The tool could have a mode for checking a single slot/epoch's rewards, or a range. It could load the block/attestation/sync committee rewards using the API, and then load the relevant pre-state/post-state using the API, and compare the rewards to the difference in balance.

This tool could exist as a standalone repo outside Lighthouse, but could import e.g. eth2/common to reuse HTTP client logic. It will need to connect to an archive beacon node. Preferably running hdiffs:

• Hierarchical state diffs #5978

Complications

The rewards APIs are known not to have full coverage. They do not handle penalties from the inactivity leak. We may want to add a mode to the range checking that warns when a range breaks the balance diff but then tries to continue (without allowing the incorrect balance to propagate).