## Issue Addressed
Attempt to fix#3812
## Proposed Changes
Move web3signer binary download script out of build script to avoid downloading unless necessary. If this works, it should also reduce the build time for all jobs that runs compilation.
> This is currently a WIP and all features are subject to alteration or removal at any time.
## Overview
The successor to #2873.
Contains the backbone of `beacon.watch` including syncing code, the initial API, and several core database tables.
See `watch/README.md` for more information, requirements and usage.
## Issue Addressed
#4127. PR to test port conflicts in CI tests .
## Proposed Changes
See issue for more details, potential solution could be adding a cache bound by time to the `unused_port` function.
## Issue Addressed
#3708
## Proposed Changes
- Add `is_finalized_block` method to `BeaconChain` in `beacon_node/beacon_chain/src/beacon_chain.rs`.
- Add `is_finalized_state` method to `BeaconChain` in `beacon_node/beacon_chain/src/beacon_chain.rs`.
- Add `fork_and_execution_optimistic_and_finalized` in `beacon_node/http_api/src/state_id.rs`.
- Add `ExecutionOptimisticFinalizedForkVersionedResponse` type in `consensus/types/src/fork_versioned_response.rs`.
- Add `execution_optimistic_finalized_fork_versioned_response`function in `beacon_node/http_api/src/version.rs`.
- Add `ExecutionOptimisticFinalizedResponse` type in `common/eth2/src/types.rs`.
- Add `add_execution_optimistic_finalized` method in `common/eth2/src/types.rs`.
- Update API response methods to include finalized.
- Remove `execution_optimistic_fork_versioned_response`
Co-authored-by: Michael Sproul <michael@sigmaprime.io>
## Proposed Changes
To prevent breakages from `cargo update`, this updates the `arbitrary` crate to a new commit from my fork. Unfortunately we still need to use my fork (even though my `bound` change was merged) because of this issue: https://github.com/rust-lang/rust-clippy/issues/10185.
In a couple of Rust versions it should be resolved upstream.
## Issue Addressed
NA
## Proposed Changes
- Bump versions.
- Bump openssl version to resolve various `cargo audit` notices.
## Additional Info
- Requires further testing
* introduce availability pending block
* add intoavailableblock trait
* small fixes
* add 'gossip blob cache' and start to clean up processing and transition types
* shard memory blob cache
* Initial commit
* Fix after rebase
* Add gossip verification conditions
* cache cleanup
* general chaos
* extended chaos
* cargo fmt
* more progress
* more progress
* tons of changes, just tryna compile
* everything, everywhere, all at once
* Reprocess an ExecutedBlock on unavailable blobs
* Add sus gossip verification for blobs
* Merge stuff
* Remove reprocessing cache stuff
* lint
* Add a wrapper to allow construction of only valid `AvailableBlock`s
* rename blob arc list to blob list
* merge cleanuo
* Revert "merge cleanuo"
This reverts commit 5e98326878c77528d0c4668c5a4db4a4b0fbaeaa.
* Revert "Revert "merge cleanuo""
This reverts commit 3a4009443a5812b3028abe855079307436dc5419.
* fix rpc methods
* move beacon block and blob to eth2/types
* rename gossip blob cache to data availability checker
* lots of changes
* fix some compilation issues
* fix compilation issues
* fix compilation issues
* fix compilation issues
* fix compilation issues
* fix compilation issues
* cargo fmt
* use a common data structure for block import types
* fix availability check on proposal import
* refactor the blob cache and split the block wrapper into two types
* add type conversion for signed block and block wrapper
* fix beacon chain tests and do some renaming, add some comments
* Partial processing (#4)
* move beacon block and blob to eth2/types
* rename gossip blob cache to data availability checker
* lots of changes
* fix some compilation issues
* fix compilation issues
* fix compilation issues
* fix compilation issues
* fix compilation issues
* fix compilation issues
* cargo fmt
* use a common data structure for block import types
* fix availability check on proposal import
* refactor the blob cache and split the block wrapper into two types
* add type conversion for signed block and block wrapper
* fix beacon chain tests and do some renaming, add some comments
* cargo update (#6)
---------
Co-authored-by: realbigsean <sean@sigmaprime.io>
Co-authored-by: realbigsean <seananderson33@gmail.com>
Currently Lighthouse will remain uncontactable if users port forward a port that is not the same as the one they are listening on.
For example, if Lighthouse runs with port 9000 TCP/UDP locally but a router is configured to pass 9010 externally to the lighthouse node on 9000, other nodes on the network will not be able to reach the lighthouse node.
This occurs because Lighthouse does not update its ENR TCP port on external socket discovery. The intention was always that users should use `--enr-tcp-port` to customise this, but this is non-intuitive.
The difficulty arises because we have no discovery mechanism to find our external TCP port. If we discovery a new external UDP port, we must guess what our external TCP port might be. This PR assumes the external TCP port is the same as the external UDP port (which may not be the case) and thus updates the TCP port along with the UDP port if the `--enr-tcp-port` flag is not set.
Along with this PR, will be added documentation to the Lighthouse book so users can correctly understand and configure their ENR to maximize Lighthouse's connectivity.
This relies on https://github.com/sigp/discv5/pull/166 and we should wait for a new release in discv5 before adding this PR.
There is a race condition which occurs when multiple discovery queries return at almost the exact same time and they independently contain a useful peer we would like to connect to.
The condition can occur that we can add the same peer to the dial queue, before we get a chance to process the queue.
This ends up displaying an error to the user:
```
ERRO Dialing an already dialing peer
```
Although this error is harmless it's not ideal.
There are two solutions to resolving this:
1. As we decide to dial the peer, we change the state in the peer-db to dialing (before we add it to the queue) which would prevent other requests from adding to the queue.
2. We prevent duplicates in the dial queue
This PR has opted for 2. because 1. will complicate the code in that we are changing states in non-intuitive places. Although this technically adds a very slight performance cost, its probably a cleaner solution as we can keep the state-changing logic in one place.
## Proposed Changes
Fix the cargo audit failure caused by [RUSTSEC-2023-0018](https://rustsec.org/advisories/RUSTSEC-2023-0018) which we were exposed to via `tempfile`.
## Additional Info
I've held back the libp2p crate for now because it seemed to introduce another duplicate dependency on libp2p-core, for a total of 3 copies. Maybe that's fine, but we can sort it out later.
## Issue Addressed
Cleans up all the remnants of 4844 in capella. This makes sure when 4844 is reviewed there is nothing we are missing because it got included here
## Proposed Changes
drop a bomb on every 4844 thing
## Additional Info
Merge process I did (locally) is as follows:
- squash merge to produce one commit
- in new branch off unstable with the squashed commit create a `git revert HEAD` commit
- merge that new branch onto 4844 with `--strategy ours`
- compare local 4844 to remote 4844 and make sure the diff is empty
- enjoy
Co-authored-by: Paul Hauner <paul@paulhauner.com>
## Issue Addressed
NA
## Proposed Changes
- Bump versions
## Sepolia Capella Upgrade
This release will enable the Capella fork on Sepolia. We are planning to publish this release on the 23rd of Feb 2023.
Users who can build from source and wish to do pre-release testing can use this branch.
## Additional Info
- [ ] Requires further testing
## Issue Addressed
#3804
## Proposed Changes
- Add `total_balance` to the validator monitor and adjust the number of historical epochs which are cached.
- Allow certain values in the cache to be served out via the HTTP API without requiring a state read.
## Usage
```
curl -X POST "http://localhost:5052/lighthouse/ui/validator_info" -d '{"indices": [0]}' -H "Content-Type: application/json" | jq
```
```
{
"data": {
"validators": {
"0": {
"info": [
{
"epoch": 172981,
"total_balance": 36566388519
},
...
{
"epoch": 172990,
"total_balance": 36566496513
}
]
},
"1": {
"info": [
{
"epoch": 172981,
"total_balance": 36355797968
},
...
{
"epoch": 172990,
"total_balance": 36355905962
}
]
}
}
}
}
```
## Additional Info
This requires no historical states to operate which mean it will still function on the freshly checkpoint synced node, however because of this, the values will populate each epoch (up to a maximum of 10 entries).
Another benefit of this method, is that we can easily cache any other values which would normally require a state read and serve them via the same endpoint. However, we would need be cautious about not overly increasing block processing time by caching values from complex computations.
This also caches some of the validator metrics directly, rather than pulling them from the Prometheus metrics when the API is called. This means when the validator count exceeds the individual monitor threshold, the cached values will still be available.
Co-authored-by: Paul Hauner <paul@paulhauner.com>
## Proposed Changes
* Bump Go from 1.17 to 1.20. The latest Geth release v1.11.0 requires 1.18 minimum.
* Prevent a cache miss during payload building by using the right fee recipient. This prevents Geth v1.11.0 from building a block with 0 transactions. The payload building mechanism is overhauled in the new Geth to improve the payload every 2s, and the tests were failing because we were falling back on a `getPayload` call with no lookahead due to `get_payload_id` cache miss caused by the mismatched fee recipient. Alternatively we could hack the tests to send `proposer_preparation_data`, but I think the static fee recipient is simpler for now.
* Add support for optionally enabling Lighthouse logs in the integration tests. Enable using `cargo run --release --features logging/test_logger`. This was very useful for debugging.
On heavily crowded networks, we are seeing many attempted connections to our node every second.
Often these connections come from peers that have just been disconnected. This can be for a number of reasons including:
- We have deemed them to be not as useful as other peers
- They have performed poorly
- They have dropped the connection with us
- The connection was spontaneously lost
- They were randomly removed because we have too many peers
In all of these cases, if we have reached or exceeded our target peer limit, there is no desire to accept new connections immediately after the disconnect from these peers. In fact, it often costs us resources to handle the established connections and defeats some of the logic of dropping them in the first place.
This PR adds a timeout, that prevents recently disconnected peers from reconnecting to us.
Technically we implement a ban at the swarm layer to prevent immediate re connections for at least 10 minutes. I decided to keep this light, and use a time-based LRUCache which only gets updated during the peer manager heartbeat to prevent added stress of polling a delay map for what could be a large number of peers.
This cache is bounded in time. An extra space bound could be added should people consider this a risk.
Co-authored-by: Diva M <divma@protonmail.com>
## Issue Addressed
NA
## Proposed Changes
Our `ERRO` stream has been rather noisy since the merge due to some unexpected behaviours of builders and EEs. Now that we've been running post-merge for a while, I think we can drop some of these `ERRO` to `WARN` so we're not "crying wolf".
The modified logs are:
#### `ERRO Execution engine call failed`
I'm seeing this quite frequently on Geth nodes. They seem to timeout when they're busy and it rarely indicates a serious issue. We also have logging across block import, fork choice updating and payload production that raise `ERRO` or `CRIT` when the EE times out, so I think we're not at risk of silencing actual issues.
#### `ERRO "Builder failed to reveal payload"`
In #3775 we reduced this log from `CRIT` to `ERRO` since it's common for builders to fail to reveal the block to the producer directly whilst still broadcasting it to the networ. I think it's worth dropping this to `WARN` since it's rarely interesting.
I elected to stay with `WARN` since I really do wish builders would fulfill their API promises by returning the block to us. Perhaps I'm just being pedantic here, I could be convinced otherwise.
#### `ERRO "Relay error when registering validator(s)"`
It seems like builders and/or mev-boost struggle to handle heavy loads of validator registrations. I haven't observed issues with validators not actually being registered, but I see timeouts on these endpoints many times a day. It doesn't seem like this `ERRO` is worth it.
#### `ERRO Error fetching block for peer ExecutionLayerErrorPayloadReconstruction`
This means we failed to respond to a peer on the P2P network with a block they requested because of an error in the `execution_layer`. It's very common to see timeouts or incomplete responses on this endpoint whilst the EE is busy and I don't think it's important enough for an `ERRO`. As long as the peer count stays high, I don't think the user needs to be actively concerned about how we're responding to peers.
## Additional Info
NA
## Issue Addressed
Resolves the cargo-audit failure caused by https://rustsec.org/advisories/RUSTSEC-2023-0010.
I also removed the ignore for `RUSTSEC-2020-0159` as we are no longer using a vulnerable version of `chrono`. We still need the other ignore for `time 0.1` because we depend on it via `sloggers -> chrono -> time 0.1`.
* Add first efforts at broadcast
* Tidy
* Move broadcast code to client
* Progress with broadcast impl
* Rename to address change
* Fix compile errors
* Use `while` loop
* Tidy
* Flip broadcast condition
* Switch to forgetting individual indices
* Always broadcast when the node starts
* Refactor into two functions
* Add testing
* Add another test
* Tidy, add more testing
* Tidy
* Add test, rename enum
* Rename enum again
* Tidy
* Break loop early
* Add V15 schema migration
* Bump schema version
* Progress with migration
* Update beacon_node/client/src/address_change_broadcast.rs
Co-authored-by: Michael Sproul <micsproul@gmail.com>
* Fix typo in function name
---------
Co-authored-by: Michael Sproul <micsproul@gmail.com>
## Proposed Changes
Remove the `[patch]` for `fixed-hash`.
We pinned it years ago in #2710 to fix `arbitrary` support. Nowadays the 0.7 version of `fixed-hash` is only used by the `web3` crate and doesn't need `arbitrary`.
~~Blocked on #3916 but could be merged in the same Bors batch.~~
## Proposed Changes
Another `tree-states` motivated PR, this adds `jemalloc` as the default allocator, with an option to use the system allocator by compiling with `FEATURES="" make`.
- [x] Metrics
- [x] Test on Windows
- [x] Test on macOS
- [x] Test with `musl`
- [x] Metrics dashboard on `lighthouse-metrics` (https://github.com/sigp/lighthouse-metrics/pull/37)
Co-authored-by: Michael Sproul <micsproul@gmail.com>
## Proposed Changes
Another `tree-states` motivated PR, this adds `jemalloc` as the default allocator, with an option to use the system allocator by compiling with `FEATURES="" make`.
- [x] Metrics
- [x] Test on Windows
- [x] Test on macOS
- [x] Test with `musl`
- [x] Metrics dashboard on `lighthouse-metrics` (https://github.com/sigp/lighthouse-metrics/pull/37)
Co-authored-by: Michael Sproul <micsproul@gmail.com>
## Proposed Changes
Update all dependencies to new semver-compatible releases with `cargo update`. Importantly this patches a Tokio vuln: https://rustsec.org/advisories/RUSTSEC-2023-0001. I don't think we were affected by the vuln because it only applies to named pipes on Windows, but it's still good hygiene to patch.
## Issue Addressed
Recent discussions with other client devs about optimistic sync have revealed a conceptual issue with the optimisation implemented in #3738. In designing that feature I failed to consider that the execution node checks the `blockHash` of the execution payload before responding with `SYNCING`, and that omitting this check entirely results in a degradation of the full node's validation. A node omitting the `blockHash` checks could be tricked by a supermajority of validators into following an invalid chain, something which is ordinarily impossible.
## Proposed Changes
I've added verification of the `payload.block_hash` in Lighthouse. In case of failure we log a warning and fall back to verifying the payload with the execution client.
I've used our existing dependency on `ethers_core` for RLP support, and a new dependency on Parity's `triehash` crate for the Merkle patricia trie. Although the `triehash` crate is currently unmaintained it seems like our best option at the moment (it is also used by Reth, and requires vastly less boilerplate than Parity's generic `trie-root` library).
Block hash verification is pretty quick, about 500us per block on my machine (mainnet).
The optimistic finalized sync feature can be disabled using `--disable-optimistic-finalized-sync` which forces full verification with the EL.
## Additional Info
This PR also introduces a new dependency on our [`metastruct`](https://github.com/sigp/metastruct) library, which was perfectly suited to the RLP serialization method. There will likely be changes as `metastruct` grows, but I think this is a good way to start dogfooding it.
I took inspiration from some Parity and Reth code while writing this, and have preserved the relevant license headers on the files containing code that was copied and modified.
I've needed to do this work in order to do some episub testing.
This version of libp2p has not yet been released, so this is left as a draft for when we wish to update.
Co-authored-by: Diva M <divma@protonmail.com>
## Proposed Changes
With proposer boosting implemented (#2822) we have an opportunity to re-org out late blocks.
This PR adds three flags to the BN to control this behaviour:
* `--disable-proposer-reorgs`: turn aggressive re-orging off (it's on by default).
* `--proposer-reorg-threshold N`: attempt to orphan blocks with less than N% of the committee vote. If this parameter isn't set then N defaults to 20% when the feature is enabled.
* `--proposer-reorg-epochs-since-finalization N`: only attempt to re-org late blocks when the number of epochs since finalization is less than or equal to N. The default is 2 epochs, meaning re-orgs will only be attempted when the chain is finalizing optimally.
For safety Lighthouse will only attempt a re-org under very specific conditions:
1. The block being proposed is 1 slot after the canonical head, and the canonical head is 1 slot after its parent. i.e. at slot `n + 1` rather than building on the block from slot `n` we build on the block from slot `n - 1`.
2. The current canonical head received less than N% of the committee vote. N should be set depending on the proposer boost fraction itself, the fraction of the network that is believed to be applying it, and the size of the largest entity that could be hoarding votes.
3. The current canonical head arrived after the attestation deadline from our perspective. This condition was only added to support suppression of forkchoiceUpdated messages, but makes intuitive sense.
4. The block is being proposed in the first 2 seconds of the slot. This gives it time to propagate and receive the proposer boost.
## Additional Info
For the initial idea and background, see: https://github.com/ethereum/consensus-specs/pull/2353#issuecomment-950238004
There is also a specification for this feature here: https://github.com/ethereum/consensus-specs/pull/3034
Co-authored-by: Michael Sproul <micsproul@gmail.com>
Co-authored-by: pawan <pawandhananjay@gmail.com>
## Issue Addressed
NA
## Proposed Changes
- Bump versions
- Pin the `nethermind` version since our method of getting the latest tags on `master` is giving us an old version (`1.14.1`).
- Increase timeout for execution engine startup.
## Additional Info
- [x] ~Awaiting further testing~
This PR adds some health endpoints for the beacon node and the validator client.
Specifically it adds the endpoint:
`/lighthouse/ui/health`
These are not entirely stable yet. But provide a base for modification for our UI.
These also may have issues with various platforms and may need modification.
## Issue Addressed
This PR addresses partially #3651
## Proposed Changes
This PR adds the following methods:
* a new method to trait `TreeHash`, `hash_tree_leaves` which returns all the Merkle leaves of the ssz object.
* a new method to `BeaconState`: `compute_merkle_proof` which generates a specific merkle proof for given depth and index by using the `hash_tree_leaves` as leaves function.
## Additional Info
Now here is some rationale on why I decided to go down this route: adding a new function to commonly used trait is a pain but was necessary to make sure we have all merkle leaves for every object, that is why I just added `hash_tree_leaves` in the trait and not `compute_merkle_proof` as well. although it would make sense it gives us code duplication/harder review time and we just need it from one specific object in one specific usecase so not worth the effort YET. In my humble opinion.
Co-authored-by: Michael Sproul <micsproul@gmail.com>
## Summary
The deposit cache now has the ability to finalize deposits. This will cause it to drop unneeded deposit logs and hashes in the deposit Merkle tree that are no longer required to construct deposit proofs. The cache is finalized whenever the latest finalized checkpoint has a new `Eth1Data` with all deposits imported.
This has three benefits:
1. Improves the speed of constructing Merkle proofs for deposits as we can just replay deposits since the last finalized checkpoint instead of all historical deposits when re-constructing the Merkle tree.
2. Significantly faster weak subjectivity sync as the deposit cache can be transferred to the newly syncing node in compressed form. The Merkle tree that stores `N` finalized deposits requires a maximum of `log2(N)` hashes. The newly syncing node then only needs to download deposits since the last finalized checkpoint to have a full tree.
3. Future proofing in preparation for [EIP-4444](https://eips.ethereum.org/EIPS/eip-4444) as execution nodes will no longer be required to store logs permanently so we won't always have all historical logs available to us.
## More Details
Image to illustrate how the deposit contract merkle tree evolves and finalizes along with the resulting `DepositTreeSnapshot`
![image](https://user-images.githubusercontent.com/37123614/151465302-5fc56284-8a69-4998-b20e-45db3934ac70.png)
## Other Considerations
I've changed the structure of the `SszDepositCache` so once you load & save your database from this version of lighthouse, you will no longer be able to load it from older versions.
Co-authored-by: ethDreamer <37123614+ethDreamer@users.noreply.github.com>
## Issue Addressed
Updates discv5
Pending on
- [x] #3547
- [x] Alex upgrades his deps
## Proposed Changes
updates discv5 and the enr crate. The only relevant change would be some clear indications of ipv4 usage in lighthouse
## Additional Info
Functionally, this should be equivalent to the prev version.
As draft pending a discv5 release
* add capella gossip boiler plate
* get everything compiling
Co-authored-by: realbigsean <sean@sigmaprime.io
Co-authored-by: Mark Mackey <mark@sigmaprime.io>
* small cleanup
* small cleanup
* cargo fix + some test cleanup
* improve block production
* add fixme for potential panic
Co-authored-by: Mark Mackey <mark@sigmaprime.io>
## Issue Addressed
NA
## Proposed Changes
Bump version to `v3.2.0`
## Additional Info
- ~~Blocked on #3597~~
- ~~Blocked on #3645~~
- ~~Blocked on #3653~~
- ~~Requires additional testing~~
## Issue Addressed
Implements new optimistic sync test format from https://github.com/ethereum/consensus-specs/pull/2982.
## Proposed Changes
- Add parsing and runner support for the new test format.
- Extend the mock EL with a set of canned responses keyed by block hash. Although this doubles up on some of the existing functionality I think it's really nice to use compared to the `preloaded_responses` or static responses. I think we could write novel new opt sync tests using these primtives much more easily than the previous ones. Forks are natively supported, and different responses to `forkchoiceUpdated` and `newPayload` are also straight-forward.
## Additional Info
Blocked on merge of the spec PR and release of new test vectors.
## Issue Addressed
#2847
## Proposed Changes
Add under a feature flag the required changes to subscribe to long lived subnets in a deterministic way
## Additional Info
There is an additional required change that is actually searching for peers using the prefix, but I find that it's best to make this change in the future
## Issue Addressed
Adding CLI tests for logging flags: log-color and disable-log-timestamp
Which issue # does this PR address?
#3588
## Proposed Changes
Add CLI tests for logging flags as described in #3588
Please list or describe the changes introduced by this PR.
Added logger_config to client::Config as suggested. Implemented Default for LoggerConfig based on what was being done elsewhere in the repo. Created 2 tests for each flag addressed.
## Additional Info
Please provide any additional information. For example, future considerations
or information useful for reviewers.
## Issue Addressed
N/A
## Proposed Changes
With https://github.com/sigp/lighthouse/pull/3214 we made it such that you can either have 1 auth endpoint or multiple non auth endpoints. Now that we are post merge on all networks (testnets and mainnet), we cannot progress a chain without a dedicated auth execution layer connection so there is no point in having a non-auth eth1-endpoint for syncing deposit cache.
This code removes all fallback related code in the eth1 service. We still keep the single non-auth endpoint since it's useful for testing.
## Additional Info
This removes all eth1 fallback related metrics that were relevant for the monitoring service, so we might need to change the api upstream.
## Issue Addressed
NA
## Proposed Changes
Fixes an issue introduced in #3574 where I erroneously assumed that a `crossbeam_channel` multiple receiver queue was a *broadcast* queue. This is incorrect, each message will be received by *only one* receiver. The effect of this mistake is these logs:
```
Sep 20 06:56:17.001 INFO Synced slot: 4736079, block: 0xaa8a…180d, epoch: 148002, finalized_epoch: 148000, finalized_root: 0x2775…47f2, exec_hash: 0x2ca5…ffde (verified), peers: 6, service: slot_notifier
Sep 20 06:56:23.237 ERRO Unable to validate attestation error: CommitteeCacheWait(RecvError), peer_id: 16Uiu2HAm2Jnnj8868tb7hCta1rmkXUf5YjqUH1YPj35DCwNyeEzs, type: "aggregated", slot: Slot(4736047), beacon_block_root: 0x88d318534b1010e0ebd79aed60b6b6da1d70357d72b271c01adf55c2b46206c1
```
## Additional Info
NA
## Issue Addressed
NA
## Proposed Changes
I have observed scenarios on Goerli where Lighthouse was receiving attestations which reference the same, un-cached shuffling on multiple threads at the same time. Lighthouse was then loading the same state from database and determining the shuffling on multiple threads at the same time. This is unnecessary load on the disk and RAM.
This PR modifies the shuffling cache so that each entry can be either:
- A committee
- A promise for a committee (i.e., a `crossbeam_channel::Receiver`)
Now, in the scenario where we have thread A and thread B simultaneously requesting the same un-cached shuffling, we will have the following:
1. Thread A will take the write-lock on the shuffling cache, find that there's no cached committee and then create a "promise" (a `crossbeam_channel::Sender`) for a committee before dropping the write-lock.
1. Thread B will then be allowed to take the write-lock for the shuffling cache and find the promise created by thread A. It will block the current thread waiting for thread A to fulfill that promise.
1. Thread A will load the state from disk, obtain the shuffling, send it down the channel, insert the entry into the cache and then continue to verify the attestation.
1. Thread B will then receive the shuffling from the receiver, be un-blocked and then continue to verify the attestation.
In the case where thread A fails to generate the shuffling and drops the sender, the next time that specific shuffling is requested we will detect that the channel is disconnected and return a `None` entry for that shuffling. This will cause the shuffling to be re-calculated.
## Additional Info
NA
## Issue Addressed
Fix a `cargo-audit` failure. We don't use `axum` for anything besides tests, but `cargo-audit` is failing due to this vulnerability in `axum-core`: https://rustsec.org/advisories/RUSTSEC-2022-0055
## Issue Addressed
We were unable to update lighthouse by running `cargo update` because some of the `mev-build-rs` deps weren't pinned. But `mev-build-rs` is now pinned here and includes it's own pinned commits for `ssz-rs` and `etheruem-consensus`
Co-authored-by: realbigsean <sean@sigmaprime.io>