6c375205fb
## Issue Addressed
Fix an issue observed by `@zlan` on Discord where Lighthouse would sometimes return this error when looking up states via the API:
> {"code":500,"message":"UNHANDLED_ERROR: ForkChoiceError(MissingProtoArrayBlock(0xc9cf1495421b6ef3215d82253b388d77321176a1dcef0db0e71a0cd0ffc8cdb7))","stacktraces":[]}
## Proposed Changes
The error stems from a faulty assumption in the HTTP API logic: that any state in the hot database must have its block in fork choice. This isn't true because the state's hot database may update much less frequently than the fork choice store, e.g. if reconstructing states (where freezer migration pauses), or if the freezer migration runs slowly. There could also be a race between loading the hot state and checking fork choice, e.g. even if the finalization migration of DB+fork choice were atomic, the update could happen between the 1st and 2nd calls.
To address this I've changed the HTTP API logic to use the finalized block's execution status as a fallback where it is safe to do so. In the case where a block is non-canonical and prior to finalization (permanently orphaned) we default `execution_optimistic` to `true`.
## Additional Info
I've also added a new CLI flag to reduce the frequency of the finalization migration as this is useful for several purposes:
- Spacing out database writes (less frequent, larger batches)
- Keeping a limited chain history with high availability, e.g. the last month in the hot database.
This new flag made it _substantially_ easier to test this change. It was extracted from `tree-states` (where it's called `--db-migration-period`), which is why this PR also carries the `tree-states` label.
Lighthouse: Ethereum consensus client
An open-source Ethereum consensus client, written in Rust and maintained by Sigma Prime.
Overview
Lighthouse is:
- Ready for use on Ethereum consensus mainnet.
- Fully open-source, licensed under Apache 2.0.
- Security-focused. Fuzzing techniques have been continuously applied and several external security reviews have been performed.
- Built in Rust, a modern language providing unique safety guarantees and excellent performance (comparable to C++).
- Funded by various organisations, including Sigma Prime, the Ethereum Foundation, ConsenSys, the Decentralization Foundation and private individuals.
- Actively involved in the specification and security analysis of the Ethereum proof-of-stake consensus specification.
Staking Deposit Contract
The Lighthouse team acknowledges
0x00000000219ab540356cBB839Cbe05303d7705Fa
as the canonical staking deposit contract address.
Documentation
The Lighthouse Book contains information for users and developers.
The Lighthouse team maintains a blog at lighthouse-blog.sigmaprime.io which contains periodical progress updates, roadmap insights and interesting findings.
Branches
Lighthouse maintains two permanent branches:
stable: Always points to the latest stable release.- This is ideal for most users.
unstable: Used for development, contains the latest PRs.- Developers should base their PRs on this branch.
Contributing
Lighthouse welcomes contributors.
If you are looking to contribute, please head to the Contributing section of the Lighthouse book.
Contact
The best place for discussion is the Lighthouse Discord server.
Sign up to the Lighthouse Development Updates mailing list for email notifications about releases, network status and other important information.
Encrypt sensitive messages using our PGP key.
Donations
Lighthouse is an open-source project and a public good. Funding public goods is hard and we're grateful for the donations we receive from the community via:
- Gitcoin Grants.
- Ethereum address:
0x25c4a76E7d118705e7Ea2e9b7d8C59930d8aCD3b(donation.sigmaprime.eth).