## Issue Addressed
Relates to https://github.com/sigp/lighthouse/issues/3416
## Proposed Changes
- Add an `OfflineOnFailure` enum to the `first_success` method for querying beacon nodes so that a val registration request failure from the BN -> builder does not result in the BN being marked offline. This seems important because these failures could be coming directly from a connected relay and actually have no bearing on BN health. Other messages that are sent to a relay have a local fallback so shouldn't result in errors
- Downgrade the following log to a `WARN`
```
ERRO Unable to publish validator registrations to the builder network, error: All endpoints failed https://BN_B => RequestFailed(ServerMessage(ErrorMessage { code: 500, message: "UNHANDLED_ERROR: BuilderMissing", stacktraces: [] })), https://XXXX/ => Unavailable(Offline), [omitted]
```
## Additional Info
I think this change at least improves the UX of having a VC connected to some builder and some non-builder beacon nodes. I think we need to balance potentially alerting users that there is a BN <> VC misconfiguration and also allowing this type of fallback to work.
If we want to fully support this type of configuration we may want to consider adding a flag `--builder-beacon-nodes` and track whether a VC should be making builder queries on a per-beacon node basis. But I think the changes in this PR are independent of that type of extension.
PS: Sorry for the big diff here, it's mostly formatting changes after I added a new arg to a bunch of methods calls.
Co-authored-by: realbigsean <sean@sigmaprime.io>
## Issue Addressed
https://github.com/sigp/lighthouse/issues/3091
Extends https://github.com/sigp/lighthouse/pull/3062, adding pre-bellatrix block support on blinded endpoints and allowing the normal proposal flow (local payload construction) on blinded endpoints. This resulted in better fallback logic because the VC will not have to switch endpoints on failure in the BN <> Builder API, the BN can just fallback immediately and without repeating block processing that it shouldn't need to. We can also keep VC fallback from the VC<>BN API's blinded endpoint to full endpoint.
## Proposed Changes
- Pre-bellatrix blocks on blinded endpoints
- Add a new `PayloadCache` to the execution layer
- Better fallback-from-builder logic
## Todos
- [x] Remove VC transition logic
- [x] Add logic to only enable builder flow after Merge transition finalization
- [x] Tests
- [x] Fix metrics
- [x] Rustdocs
Co-authored-by: Mac L <mjladson@pm.me>
Co-authored-by: realbigsean <sean@sigmaprime.io>
## Issue Addressed
* #3173
## Proposed Changes
Moved all `fee_recipient_file` related logic inside the `ValidatorStore` as it makes more sense to have this all together there. I tested this with the validators I have on `mainnet-shadow-fork-5` and everything appeared to work well. Only technicality is that I can't get the method to return `401` when the authorization header is not specified (it returns `400` instead). Fixing this is probably quite difficult given that none of `warp`'s rejections have code `401`.. I don't really think this matters too much though as long as it fails.
## Issue Addressed
Lays the groundwork for builder API changes by implementing the beacon-API's new `register_validator` endpoint
## Proposed Changes
- Add a routine in the VC that runs on startup (re-try until success), once per epoch or whenever `suggested_fee_recipient` is updated, signing `ValidatorRegistrationData` and sending it to the BN.
- TODO: `gas_limit` config options https://github.com/ethereum/builder-specs/issues/17
- BN only sends VC registration data to builders on demand, but VC registration data *does update* the BN's prepare proposer cache and send an updated fcU to a local EE. This is necessary for fee recipient consistency between the blinded and full block flow in the event of fallback. Having the BN only send registration data to builders on demand gives feedback directly to the VC about relay status. Also, since the BN has no ability to sign these messages anyways (so couldn't refresh them if it wanted), and validator registration is independent of the BN head, I think this approach makes sense.
- Adds upcoming consensus spec changes for this PR https://github.com/ethereum/consensus-specs/pull/2884
- I initially applied the bit mask based on a configured application domain.. but I ended up just hard coding it here instead because that's how it's spec'd in the builder repo.
- Should application mask appear in the api?
Co-authored-by: realbigsean <sean@sigmaprime.io>
## Issue Addressed
This fixes the low-hanging Clippy lints introduced in Rust 1.61 (due any hour now). It _ignores_ one lint, because fixing it requires a structural refactor of the validator client that needs to be done delicately. I've started on that refactor and will create another PR that can be reviewed in more depth in the coming days. I think we should merge this PR in the meantime to unblock CI.
## Issue Addressed
Presently if the VC is configured with a fee recipient it will error out when sending fee-recipient preparations to a beacon node that doesn't yet support the API:
```
Mar 08 22:23:36.236 ERRO Unable to publish proposer preparation error: All endpoints failed https://eth2-beacon-prater.infura.io/ => RequestFailed(StatusCode(404)), service: preparation
```
This doesn't affect other VC duties, but could be a source of anxiety for users trying to do the right thing and configure their fee recipients in advance.
## Proposed Changes
Change the preparation service to only send preparations if the current slot is later than 2 epochs before the Bellatrix hard fork epoch.
## Additional Info
I've tagged this v2.1.4 as I think it's a small change that's worth having for the next release
## Issue Addressed
#2883
## Proposed Changes
* Added `suggested-fee-recipient` & `suggested-fee-recipient-file` flags to validator client (similar to graffiti / graffiti-file implementation).
* Added proposer preparation service to VC, which sends the fee-recipient of all known validators to the BN via [/eth/v1/validator/prepare_beacon_proposer](https://github.com/ethereum/beacon-APIs/pull/178) api once per slot
* Added [/eth/v1/validator/prepare_beacon_proposer](https://github.com/ethereum/beacon-APIs/pull/178) api endpoint and preparation data caching
* Added cleanup routine to remove cached proposer preparations when not updated for 2 epochs
## Additional Info
Changed the Implementation following the discussion in #2883.
Co-authored-by: pk910 <philipp@pk910.de>
Co-authored-by: Paul Hauner <paul@paulhauner.com>
Co-authored-by: Philipp K <philipp@pk910.de>
