## Issue Addressed
Resolves#3388Resolves#2638
## Proposed Changes
- Return the `BellatrixPreset` on `/eth/v1/config/spec` by default.
- Allow users to opt out of this by providing `--http-spec-fork=altair` (unless there's a Bellatrix fork epoch set).
- Add the Altair constants from #2638 and make serving the constants non-optional (the `http-disable-legacy-spec` flag is deprecated).
- Modify the VC to only read the `Config` and not to log extra fields. This prevents it from having to muck around parsing the `ConfigAndPreset` fields it doesn't need.
## Additional Info
This change is backwards-compatible for the VC and the BN, but is marked as a breaking change for the removal of `--http-disable-legacy-spec`.
I tried making `Config` a `superstruct` too, but getting the automatic decoding to work was a huge pain and was going to require a lot of hacks, so I gave up in favour of keeping the default-based approach we have now.
## Issue Addressed
Enable https://github.com/sigp/lighthouse/pull/3322 by default on all networks.
The feature can be opted out of using `--count-unrealized=false` (the CLI flag is updated to take a parameter).
## 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
Add a flag that optionally enables unrealized vote tracking. Would like to test out on testnets and benchmark differences in methods of vote tracking. This PR includes a DB schema upgrade to enable to new vote tracking style.
Co-authored-by: realbigsean <sean@sigmaprime.io>
Co-authored-by: Paul Hauner <paul@paulhauner.com>
Co-authored-by: sean <seananderson33@gmail.com>
Co-authored-by: Mac L <mjladson@pm.me>
## Issue Addressed
This PR is a subset of the changes in #3134. Unstable will still not function correctly with the new builder spec once this is merged, #3134 should be used on testnets
## Proposed Changes
- Removes redundancy in "builders" (servers implementing the builder spec)
- Renames `payload-builder` flag to `builder`
- Moves from old builder RPC API to new HTTP API, but does not implement the validator registration API (implemented in https://github.com/sigp/lighthouse/pull/3194)
Co-authored-by: sean <seananderson33@gmail.com>
Co-authored-by: realbigsean <sean@sigmaprime.io>
## Issue Addressed
Resolves#3069
## Proposed Changes
Unify the `eth1-endpoints` and `execution-endpoints` flags in a backwards compatible way as described in https://github.com/sigp/lighthouse/issues/3069#issuecomment-1134219221
Users have 2 options:
1. Use multiple non auth execution endpoints for deposit processing pre-merge
2. Use a single jwt authenticated execution endpoint for both execution layer and deposit processing post merge
Related https://github.com/sigp/lighthouse/issues/3118
To enable jwt authenticated deposit processing, this PR removes the calls to `net_version` as the `net` namespace is not exposed in the auth server in execution clients.
Moving away from using `networkId` is a good step in my opinion as it doesn't provide us with any added guarantees over `chainId`. See https://github.com/ethereum/consensus-specs/issues/2163 and https://github.com/sigp/lighthouse/issues/2115
Co-authored-by: Paul Hauner <paul@paulhauner.com>
## Issue Addressed
Fix for the eth1 cache sync issue observed on Ropsten.
## Proposed Changes
Ropsten blocks are so infrequent that they broke our algorithm for downloading eth1 blocks. We currently try to download forwards from the last block in our cache to the block with block number [`remote_highest_block - FOLLOW_DISTANCE + FOLLOW_DISTANCE / ETH1_BLOCK_TIME_TOLERANCE_FACTOR`](6f732986f1/beacon_node/eth1/src/service.rs (L489-L492)). With the tolerance set to 4 this is insufficient because we lag by 1536 blocks, which is more like ~14 hours on Ropsten. This results in us having an incomplete eth1 cache, because we should cache all blocks between -16h and -8h. Even if we were to set the tolerance to 2 for the largest allowance, we would only look back 1024 blocks which is still more than 8 hours.
For example consider this block https://ropsten.etherscan.io/block/12321390. The block from 1536 blocks earlier is 14 hours and 20 minutes before it: https://ropsten.etherscan.io/block/12319854. The block from 1024 blocks earlier is https://ropsten.etherscan.io/block/12320366, 8 hours and 48 minutes before.
- This PR introduces a new CLI flag called `--eth1-cache-follow-distance` which can be used to set the distance manually.
- A new dynamic catchup mechanism is added which detects when the cache is lagging the true eth1 chain and tries to download more blocks within the follow distance in order to catch up.
## Issue Addressed
Upcoming spec change https://github.com/ethereum/consensus-specs/pull/2878
## Proposed Changes
1. Run fork choice at the start of every slot, and wait for this run to complete before proposing a block.
2. As an optimisation, also run fork choice 3/4 of the way through the slot (at 9s), _dequeueing attestations for the next slot_.
3. Remove the fork choice run from the state advance timer that occurred before advancing the state.
## Additional Info
### Block Proposal Accuracy
This change makes us more likely to propose on top of the correct head in the presence of re-orgs with proposer boost in play. The main scenario that this change is designed to address is described in the linked spec issue.
### Attestation Accuracy
This change _also_ makes us more likely to attest to the correct head. Currently in the case of a skipped slot at `slot` we only run fork choice 9s into `slot - 1`. This means the attestations from `slot - 1` aren't taken into consideration, and any boost applied to the block from `slot - 1` is not removed (it should be). In the language of the linked spec issue, this means we are liable to attest to C, even when the majority voting weight has already caused a re-org to B.
### Why remove the call before the state advance?
If we've run fork choice at the start of the slot then it has already dequeued all the attestations from the previous slot, which are the only ones eligible to influence the head in the current slot. Running fork choice again is unnecessary (unless we run it for the next slot and try to pre-empt a re-org, but I don't currently think this is a great idea).
### Performance
Based on Prater testing this adds about 5-25ms of runtime to block proposal times, which are 500-1000ms on average (and spike to 5s+ sometimes due to state handling issues 😢 ). I believe this is a small enough penalty to enable it by default, with the option to disable it via the new flag `--fork-choice-before-proposal-timeout 0`. Upcoming work on block packing and state representation will also reduce block production times in general, while removing the spikes.
### Implementation
Fork choice gets invoked at the start of the slot via the `per_slot_task` function called from the slot timer. It then uses a condition variable to signal to block production that fork choice has been updated. This is a bit funky, but it seems to work. One downside of the timer-based approach is that it doesn't happen automatically in most of the tests. The test added by this PR has to trigger the run manually.
## Issue Addressed
MEV boost compatibility
## Proposed Changes
See #2987
## Additional Info
This is blocked on the stabilization of a couple specs, [here](https://github.com/ethereum/beacon-APIs/pull/194) and [here](https://github.com/flashbots/mev-boost/pull/20).
Additional TODO's and outstanding questions
- [ ] MEV boost JWT Auth
- [ ] Will `builder_proposeBlindedBlock` return the revealed payload for the BN to propogate
- [ ] Should we remove `private-tx-proposals` flag and communicate BN <> VC with blinded blocks by default once these endpoints enter the beacon-API's repo? This simplifies merge transition logic.
Co-authored-by: realbigsean <seananderson33@gmail.com>
Co-authored-by: realbigsean <sean@sigmaprime.io>
## Issue Addressed
Resolves#3015
## Proposed Changes
Add JWT token based authentication to engine api requests. The jwt secret key is read from the provided file and is used to sign tokens that are used for authenticated communication with the EL node.
- [x] Interop with geth (synced `merge-devnet-4` with the `merge-kiln-v2` branch on geth)
- [x] Interop with other EL clients (nethermind on `merge-devnet-4`)
- [x] ~Implement `zeroize` for jwt secrets~
- [x] Add auth server tests with `mock_execution_layer`
- [x] Get auth working with the `execution_engine_integration` tests
Co-authored-by: Paul Hauner <paul@paulhauner.com>
## Issue Addressed
#3006
## Proposed Changes
This PR changes the default behaviour of lighthouse to ignore discovered IPs that are not globally routable. It adds a CLI flag, --enable-local-discovery to permit the non-global IPs in discovery.
NOTE: We should take care in merging this as I will break current set-ups that rely on local IP discovery. I made this the non-default behaviour because we dont really want to be wasting resources attempting to connect to non-routable addresses and we dont want to propagate these to others (on the chance we can connect to one of these local nodes), improving discoveries efficiency.
## 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>
There is a pretty significant tradeoff between bandwidth and speed of gossipsub messages.
We can reduce our bandwidth usage considerably at the cost of minimally delaying gossipsub messages. The impact of delaying messages has not been analyzed thoroughly yet, however this PR in conjunction with some gossipsub updates show considerable bandwidth reduction.
This PR allows the user to set a CLI value (`network-load`) which is an integer in the range of 1 of 5 depending on their bandwidth appetite. 1 represents the least bandwidth but slowest message recieving and 5 represents the most bandwidth and fastest received message time.
For low-bandwidth users it is likely to be more efficient to use a lower value. The default is set to 3, which currently represents a reduced bandwidth usage compared to previous version of this PR. The previous lighthouse versions are equivalent to setting the `network-load` CLI to 4.
This PR is awaiting a few gossipsub updates before we can get it into lighthouse.
## Issue Addressed
The fee-recipient argument of the beacon node does not allow a value to be specified:
> $ lighthouse beacon_node --merge --fee-recipient "0x332E43696A505EF45b9319973785F837ce5267b9"
> error: Found argument '0x332E43696A505EF45b9319973785F837ce5267b9' which wasn't expected, or isn't valid in this context
>
> USAGE:
> lighthouse beacon_node --fee-recipient --merge
>
> For more information try --help
## Proposed Changes
Allow specifying a value for the fee-recipient argument in beacon_node/src/cli.rs
## Additional Info
I've added .takes_value(true) and successfully proposed a block in the kintsugi testnet with my own fee-recipient address instead of the hardcoded default. I think that was just missed as the argument does not make sense without a value :)
Co-authored-by: pk910 <philipp@pk910.de>
Co-authored-by: Michael Sproul <micsproul@gmail.com>
Co-authored-by: Michael Sproul <michael@sigmaprime.io>
## Issue Addressed
Closes#2286Closes#2538Closes#2342
## Proposed Changes
Part II of major slasher optimisations after #2767
These changes will be backwards-incompatible due to the move to MDBX (and the schema change) 😱
* [x] Shrink attester keys from 16 bytes to 7 bytes.
* [x] Shrink attester records from 64 bytes to 6 bytes.
* [x] Separate `DiskConfig` from regular `Config`.
* [x] Add configuration for the LRU cache size.
* [x] Add a "migration" that deletes any legacy LMDB database.
* Fix arbitrary check kintsugi
* Add merge chain spec fields, and a function to determine which constant to use based on the state variant
* increment spec test version
* Remove `Transaction` enum wrapper
* Remove Transaction new-type
* Remove gas validations
* Add `--terminal-block-hash-epoch-override` flag
* Increment spec tests version to 1.1.5
* Remove extraneous gossip verification https://github.com/ethereum/consensus-specs/pull/2687
* - Remove unused Error variants
- Require both "terminal-block-hash-epoch-override" and "terminal-block-hash-override" when either flag is used
* - Remove a couple more unused Error variants
Co-authored-by: Paul Hauner <paul@paulhauner.com>
* Thread eth1_block_hash into interop genesis state
* Add merge-fork-epoch flag
* Build LH with minimal spec by default
* Add verbose logs to execution_layer
* Add --http-allow-sync-stalled flag
* Update lcli new-testnet to create genesis state
* Fix http test
* Fix compile errors in tests
## Issue Addressed
Closes https://github.com/sigp/lighthouse/issues/2112
Closes https://github.com/sigp/lighthouse/issues/1861
## Proposed Changes
Collect attestations by validator index in the slasher, and use the magic of reference counting to automatically discard redundant attestations. This results in us storing only 1-2% of the attestations observed when subscribed to all subnets, which carries over to a 50-100x reduction in data stored 🎉
## Additional Info
There's some nuance to the configuration of the `slot-offset`. It has a profound effect on the effictiveness of de-duplication, see the docs added to the book for an explanation: 5442e695e5/book/src/slasher.md (slot-offset)
## Issue Addressed
Mitigates #1096
## Proposed Changes
Add a flag to the beacon node called `--disable-lock-timeouts` which allows opting out of lock timeouts.
The lock timeouts serve a dual purpose:
1. They prevent any single operation from hogging the lock for too long. When a timeout occurs it logs a nasty error which indicates that there's suboptimal lock use occurring, which we can then act on.
2. They allow deadlock detection. We're fairly sure there are no deadlocks left in Lighthouse anymore but the timeout locks offer a safeguard against that.
However, timeouts on locks are not without downsides:
They allow for the possibility of livelock, particularly on slower hardware. If lock timeouts keep failing spuriously the node can be prevented from making any progress, even if it would be able to make progress slowly without the timeout. One particularly concerning scenario which could occur would be if a DoS attack succeeded in slowing block signature verification times across the network, and all Lighthouse nodes got livelocked because they timed out repeatedly. This could also occur on just a subset of nodes (e.g. dual core VPSs or Raspberri Pis).
By making the behaviour runtime configurable this PR allows us to choose the behaviour we want depending on circumstance. I suspect that long term we could make the timeout-free approach the default (#2381 moves in this direction) and just enable the timeouts on our testnet nodes for debugging purposes. This PR conservatively leaves the default as-is so we can gain some more experience before switching the default.
Currently, the beacon node has no ability to serve the HTTP API over TLS.
Adding this functionality would be helpful for certain use cases, such as when you need a validator client to connect to a backup beacon node which is outside your local network, and the use of an SSH tunnel or reverse proxy would be inappropriate.
## Proposed Changes
- Add three new CLI flags to the beacon node
- `--http-enable-tls`: enables TLS
- `--http-tls-cert`: to specify the path to the certificate file
- `--http-tls-key`: to specify the path to the key file
- Update the HTTP API to optionally use `warp`'s [`TlsServer`](https://docs.rs/warp/0.3.1/warp/struct.TlsServer.html) depending on the presence of the `--http-enable-tls` flag
- Update tests and docs
- Use a custom branch for `warp` to ensure proper error handling
## Additional Info
Serving the API over TLS should currently be considered experimental. The reason for this is that it uses code from an [unmerged PR](https://github.com/seanmonstar/warp/pull/717). This commit provides the `try_bind_with_graceful_shutdown` method to `warp`, which is helpful for controlling error flow when the TLS configuration is invalid (cert/key files don't exist, incorrect permissions, etc).
I've implemented the same code in my [branch here](https://github.com/macladson/warp/tree/tls).
Once the code has been reviewed and merged upstream into `warp`, we can remove the dependency on my branch and the feature can be considered more stable.
Currently, the private key file must not be password-protected in order to be read into Lighthouse.
## Issue Addressed
Closes#1891Closes#1784
## Proposed Changes
Implement checkpoint sync for Lighthouse, enabling it to start from a weak subjectivity checkpoint.
## Additional Info
- [x] Return unavailable status for out-of-range blocks requested by peers (#2561)
- [x] Implement sync daemon for fetching historical blocks (#2561)
- [x] Verify chain hashes (either in `historical_blocks.rs` or the calling module)
- [x] Consistency check for initial block + state
- [x] Fetch the initial state and block from a beacon node HTTP endpoint
- [x] Don't crash fetching beacon states by slot from the API
- [x] Background service for state reconstruction, triggered by CLI flag or API call.
Considered out of scope for this PR:
- Drop the requirement to provide the `--checkpoint-block` (this would require some pretty heavy refactoring of block verification)
Co-authored-by: Diva M <divma@protonmail.com>
## Issue Addressed
Resolves#2033
## Proposed Changes
Adds a flag to enable shutting down beacon node right after sync is completed.
## Additional Info
Will need modification after weak subjectivity sync is enabled to change definition of a fully synced node.
## Issue Addressed
N/A
## Proposed Changes
Adds a cli option to disable packet filter in `lighthouse bootnode`. This is useful in running local testnets as the bootnode bans requests from the same ip(localhost) if the packet filter is enabled.
## Proposed Changes
Implement the consensus changes necessary for the upcoming Altair hard fork.
## Additional Info
This is quite a heavy refactor, with pivotal types like the `BeaconState` and `BeaconBlock` changing from structs to enums. This ripples through the whole codebase with field accesses changing to methods, e.g. `state.slot` => `state.slot()`.
Co-authored-by: realbigsean <seananderson33@gmail.com>
## Issue Addressed
- Resolves#2064
## Proposed Changes
Adds a `ValidatorMonitor` struct which provides additional logging and Grafana metrics for specific validators.
Use `lighthouse bn --validator-monitor` to automatically enable monitoring for any validator that hits the [subnet subscription](https://ethereum.github.io/eth2.0-APIs/#/Validator/prepareBeaconCommitteeSubnet) HTTP API endpoint.
Also, use `lighthouse bn --validator-monitor-pubkeys` to supply a list of validators which will always be monitored.
See the new docs included in this PR for more info.
## TODO
- [x] Track validator balance, `slashed` status, etc.
- [x] ~~Register slashings in current epoch, not offense epoch~~
- [ ] Publish Grafana dashboard, update TODO link in docs
- [x] ~~#2130 is merged into this branch, resolve that~~
## Issue Addressed
Closes#2048
## Proposed Changes
* Broadcast slashings when the `--slasher-broadcast` flag is provided.
* In the process of implementing this I refactored the slasher service into its own crate so that it could access the network code without creating a circular dependency. I moved the responsibility for putting slashings into the op pool into the service as well, as it makes sense for it to handle the whole slashing lifecycle.
## Issue
Some eth1 clients are missing deposit logs on mainnet for multiple reasons (not fully synced, eth1 client issues) because of which we are getting `FailedToInsertDeposit` errors.
Ideally, LH should pick up where it left off after pointing it to a nice eth1 client endpoint (which has all deposits).
However, I have seen instances where LH keeps getting `FailedToInsertDeposit` even after switching to a good endpoint. Only deleting the beacon directory (which also wipes the eth1 cache) and resyncing the eth1 caches seems to be the solution. This wouldn't be great for mainnet if you have to sync your beacon node again as well.
## Proposed Changes
Add a `--purge-eth1-db` option which just wipes the eth1 cache and doesn't touch the rest of the beacon db.
Still need to investigate if and why LH isn't picking up where it left off for the deposit logs sync, but I think it would be good to have an option to just delete eth1 caches regardless.
## Issue Addressed
Resolves#1434 (this is the last major feature in the standard spec. There are only a couple of places we may be off-spec due to recent spec changes or ongoing discussion)
Partly addresses #1669
## Proposed Changes
- remove the websocket server
- remove the `TeeEventHandler` and `NullEventHandler`
- add server sent events according to the eth2 API spec
## Additional Info
This is according to the currently unmerged PR here: https://github.com/ethereum/eth2.0-APIs/pull/117
Co-authored-by: realbigsean <seananderson33@gmail.com>
Adds a `--privacy` CLI flag to the beacon node that users may opt into.
This does two things:
- Removes client identifying information from the identify libp2p protocol
- Changes the default graffiti to "" if no graffiti is set.
## Issue Addressed
part of #1883
## Proposed Changes
Adds a new cli argument `--eth1-endpoints` that can be used instead of `--eth1-endpoint` to specify a comma-separated list of endpoints. If the first endpoint returns an error for some request the other endpoints are tried in the given order.
## Additional Info
Currently if the first endpoint fails the fallbacks are used silently (except for `try_fallback_test_endpoint` that is used in `do_update` which logs a `WARN` for each endpoint that is not reachable). A question is if we should add more logs so that the user gets warned if his main endpoint is for example just slow and sometimes hits timeouts.
This is an implementation of a slasher that lives inside the BN and can be enabled via `lighthouse bn --slasher`.
Features included in this PR:
- [x] Detection of attester slashing conditions (double votes, surrounds existing, surrounded by existing)
- [x] Integration into Lighthouse's attestation verification flow
- [x] Detection of proposer slashing conditions
- [x] Extraction of attestations from blocks as they are verified
- [x] Compression of chunks
- [x] Configurable history length
- [x] Pruning of old attestations and blocks
- [x] More tests
Future work:
* Focus on a slice of history separate from the most recent N epochs (e.g. epochs `current - K` to `current - M`)
* Run out-of-process
* Ingest attestations from the chain without a resync
Design notes are here https://hackmd.io/@sproul/HJSEklmPL
## Issue Addressed
NA
## Proposed Changes
Adds the `--import-all-attestations` flag which tells the `network::AttestationService` to import/aggregate all attestations after verification (instead of only ones for subnets that are relevant to local validators).
This is useful for testing/debugging and also for creating back-up nodes that should be all cached up and ready for any validator.
## Additional Info
NA
## Issue Addressed
NA
## Proposed Changes
Users on Discord (and @protolambda) have experienced this error (or variants of it):
```
Failed to update eth1 cache: GetDepositLogsFailed("Eth1 node returned error: {\"code\":-32005,\"message\":\"query returned more than 10000 results\"}")
```
This PR allows users to reduce the span of blocks searched for deposit logs and therefore reduce the size of the return result. Hopefully experimentation with this flag can lead to finding a better default value.
## Additional Info
NA
## Proposed Changes
In an attempt to fix OOM issues and database consistency issues observed by some users after the introduction of compaction in v0.3.4, this PR makes the following changes:
* Run compaction less often: roughly every 1024 epochs, including after long periods of non-finality. I think the division check proposed by Paul is pretty solid, and ensures we don't miss any events where we should be compacting. LevelDB lacks an easy way to check the size of the DB, which would be another good trigger.
* Make it possible to disable the compaction on finalization using `--auto-compact-db=false`
* Make it possible to trigger a manual, single-threaded foreground compaction on start-up using `--compact-db`
* Downgrade the pruning log to `DEBUG`, as it's particularly noisy during sync
I would like to ship these changes to affected users ASAP, and will document them further in the Advanced Database section of the book if they prove effective.
## Issue Addressed
- Asymmetric pings - Currently with symmetric ping intervals, lighthouse nodes race each other to ping often ending in simultaneous ping connections. This shifts the ping interval to be asymmetric based on inbound/outbound connections
- Correct inbound/outbound peer-db registering - It appears we were accounting inbound as outbound and vice versa in the peerdb, this has been corrected
- Improved logging
There is likely more to come - I'll leave this open as we investigate further testnets
## Issue Addressed
Closes#800Closes#1713
## Proposed Changes
Implement the temporary state storage algorithm described in #800. Specifically:
* Add `DBColumn::BeaconStateTemporary`, for storing 0-length temporary marker values.
* Store intermediate states immediately as they are created, marked temporary. Delete the temporary flag if the block is processed successfully.
* Add a garbage collection process to delete leftover temporary states on start-up.
* Bump the database schema version to 2 so that a DB with temporary states can't accidentally be used with older versions of the software. The auto-migration is a no-op, but puts in place some infra that we can use for future migrations (e.g. #1784)
## Additional Info
There are two known race conditions, one potentially causing permanent faults (hopefully rare), and the other insignificant.
### Race 1: Permanent state marked temporary
EDIT: this has been fixed by the addition of a lock around the relevant critical section
There are 2 threads that are trying to store 2 different blocks that share some intermediate states (e.g. they both skip some slots from the current head). Consider this sequence of events:
1. Thread 1 checks if state `s` already exists, and seeing that it doesn't, prepares an atomic commit of `(s, s_temporary_flag)`.
2. Thread 2 does the same, but also gets as far as committing the state txn, finishing the processing of its block, and _deleting_ the temporary flag.
3. Thread 1 is (finally) scheduled again, and marks `s` as temporary with its transaction.
4.
a) The process is killed, or thread 1's block fails verification and the temp flag is not deleted. This is a permanent failure! Any attempt to load state `s` will fail... hope it isn't on the main chain! Alternatively (4b) happens...
b) Thread 1 finishes, and re-deletes the temporary flag. In this case the failure is transient, state `s` will disappear temporarily, but will come back once thread 1 finishes running.
I _hope_ that steps 1-3 only happen very rarely, and 4a even more rarely. It's hard to know
This once again begs the question of why we're using LevelDB (#483), when it clearly doesn't care about atomicity! A ham-fisted fix would be to wrap the hot and cold DBs in locks, which would bring us closer to how other DBs handle read-write transactions. E.g. [LMDB only allows one R/W transaction at a time](https://docs.rs/lmdb/0.8.0/lmdb/struct.Environment.html#method.begin_rw_txn).
### Race 2: Temporary state returned from `get_state`
I don't think this race really matters, but in `load_hot_state`, if another thread stores a state between when we call `load_state_temporary_flag` and when we call `load_hot_state_summary`, then we could end up returning that state even though it's only a temporary state. I can't think of any case where this would be relevant, and I suspect if it did come up, it would be safe/recoverable (having data is safer than _not_ having data).
This could be fixed by using a LevelDB read snapshot, but that would require substantial changes to how we read all our values, so I don't think it's worth it right now.
## Issue Addressed
- Resolves#1766
## Proposed Changes
- Use the `warp::filters::cors` filter instead of our work-around.
## Additional Info
It's not trivial to enable/disable `cors` using `warp`, since using `routes.with(cors)` changes the type of `routes`. This makes it difficult to apply/not apply cors at runtime. My solution has been to *always* use the `warp::filters::cors` wrapper but when cors should be disabled, just pass the HTTP server listen address as the only permissible origin.
This commit was modified by Paul H whilst rebasing master onto
v0.3.0-staging
Adding UPnP support will help grow the DHT by allowing NAT traversal for peers with UPnP supported routers.
Using IGD library: https://docs.rs/igd/0.10.0/igd/
Adding the the libp2p tcp port and discovery udp port. If this fails it simply logs the attempt and moves on
Co-authored-by: Age Manning <Age@AgeManning.com>
This commit was edited by Paul H when rebasing from master to
v0.3.0-staging.
Solution 2 proposed here: https://github.com/sigp/lighthouse/issues/1435#issuecomment-692317639
- Adds an optional `--wss-checkpoint` flag that takes a string `root:epoch`
- Verify that the given checkpoint exists in the chain, or that the the chain syncs through this checkpoint. If not, shutdown and prompt the user to purge state before restarting.
Co-authored-by: Paul Hauner <paul@paulhauner.com>
## Issue Addressed
Closes#673
## Proposed Changes
Store a schema version in the database so that future releases can check they're running against a compatible database version. This would also enable automatic migration on breaking database changes, but that's left as future work.
The database config is also stored in the database so that the `slots_per_restore_point` value can be checked for consistency, which closes#673